Browse Topic: Steering wheels

Items (368)
Find
Self-Propelled Sweepers and Scrubbers Steering Requirements Single-Circuit Hydraulic Servo-Assisted SystemsJ1790_202111 (Current)11/9/2021
The SAE Standard applies to self-propelled, driver-operated sweepers and scrubbers as defined in SAE J2130-1 and SAE J2130-2.
MTC2, Sweeper, Cleaner, and Machinery
A Novel Velocity Planner for Autonomous Vehicle Considering Human Driver’s Habits2020-01-01334/14/2020
In automatic driving application, the velocity planner can be considered as a key factor to ensure the safety and comfort. One of the most important tasks of the velocity planner is to simulate the velocity characteristics of human drivers. In this paper, two Driver In-the-Loop (DIL) experiments are designed to explain velocity characteristics of human drivers. In the first experiment, static obstacles are placed on both sides of the straight road to shorten the cross range that vehicles can driver across. Moreover, different cross ranges are set to study the influence of the steering wheel error. In the second experiment, velocity characteristics are investigated under the condition of different road widths and curvatures in a U-turn road contour. In both tests, different drivers’ preview behavior is analyzed through the operation of throttle, braking, and steering. From the results we could see the change of vehicle speed depends largely on the traffic environment at the driver’s preview point. On this basis, a novel velocity planner is proposed. Firstly, a target velocity in preview terminal point is calculated. The calculation of the velocity is based on two indicators-the driver’s driving & operating ability, and the degree of visual restriction. The former refers to the ability of the driver to maintain the driveway as well as the control ability of the vehicle stability, and the latter is related to the uncertainty of the environment. Subsequently, the smooth velocity profiles that connect the initial point and the preview terminal point are generated based on the convex optimization. Finally, the simulation results show that this velocity planner possesses good human-like performance, considering the human-vehicle-road coordination. This study is useful to customize velocity planning for autonomous vehicle so as to improve the acceptability of the specific human driver.
Cui, Zongwei, Guo, Xuexun, Pei, Xiaofei
Trajectory Planning and Tracking for Four-Wheel-Steering Autonomous Vehicle with V2V Communication2020-01-01144/14/2020
Lane-changing is a typical traffic scene effecting on road traffic with high request for reliability, robustness and driving comfort to improve the road safety and transportation efficiency. The development of connected autonomous vehicles with V2V communication provide more advanced control strategies to research of lane-changing. Meanwhile, four-wheel steering is an effective way to improve flexibility of vehicle. The front and rear wheels rotate in opposite direction to reduce the turning radius to improve the servo agility operation at the low speed while those rotate in same direction to reduce the probability of the slip accident to improve the stability at the high speed. Hence, this paper established Four-Wheel-Steering(4WS) vehicle dynamic model and quasi real lane-changing scenes to analyze the motion constraints of the vehicles. Then, the polynomial function was used for the lane-changing trajectory planning and the extended rectangular vehicle model was established to get vehicle collision avoidance condition. Vehicle comfort requirements and lane-changing efficiency were used as the optimization variables of optimization function and the control of trajectory tracking can be obtained by using model predictive control (MPC) method. A lane-changing model based on steering characteristics and safety distance with the system of V2V communication and collaboration strategy was established. The lane-changing trajectory was simulated by MATLAB and the results showed that the lane-changing trajectory can safely realize the lane-changing behavior of 4WS autonomous vehicles.
Ma, Fangwu, Shen, Yucheng, Nie, Jiahong, Li, Xiyu, Yang, Yu, Wang, Jiawei, Wu, Guanpu
The Effect of An Acoustic Startling Warning On Take-Over Reaction Time And Trunk Kinematics for Drivers in Autonomous Driving Scenarios2019-22-00223/31/2020
The Acoustic Startling Pre-stimulus (ASPS, i.e. a loud sound preceding a physical perturbation) was previously found to accelerate action execution in simple flexion exercises. Therefore in this study we examined if ASPS can accelerate take-over reaction times in restrained teen and adult drivers who were asked to reach for the steering wheel while experiencing sled lateral perturbations simulating a vehicle swerve. Results showed that adult drivers lift their hands toward the steering wheel faster with the ASPS versus without (161 ± 23 ms vs 216 ± 27 ms, p<0.003). However this effect was not found in teens or in trials where the drivers were engaged in a secondary task. Adults also showed reduced lateral trunk displacement out of the seat belt with the ASPS. The ASPS could represent a novel warning that reduces take over time and out-of-position movements in critical autonomous driving scenarios.
Graci, Valentina, Griffith, Madeline, Maheshwari, Jalaj, Akkem, Rahul, Austin, Meta, Seacrist, Thomas, Arbogast, Kristy B.
JLR tackles weight with structural electronics20AUTP03_103/1/2020
Ashutosh Tomar, electrical research technical manager at Jaguar Land Rover (JLR) said he has absolute confidence in the potential of structural electronics (SE) now being pioneered by the company. Dubbed LESA (Lightweight Electronics in Simplified Architecture), the technology is expected in upcoming JLR models, though its use in the next-generation Jaguar XJ to be launched in 2020 has not been confirmed. JLR is completing a successful R&D program into printed SE, initially to introduce curved dashboard screens. The company claims an industry first that has the potential to radically alter vehicle interiors, with other applications forthcoming. SE is not a new technology. Decades ago the aerospace industry was considering it as part of aircraft-surface morphing capability to adapt to varying flight conditions.
Birch, Stuart
A Real-Time Obstacle-Avoidance Trajectory Planner for On-Road Autonomous Vehicle2020-01-50182/24/2020
A real-time obstacle-avoidance trajectory planner for on-road autonomous vehicle is proposed in this paper. A cubic B spline core is parametric to generate path with continuous curvature as well as taking the extreme curvature limited by steer system into account. By sampling the target sets via offsetting along the reference path, lots path sets are produced with same heading. As embedded with collision checker and path evaluator, a path selector could pick out the best one to planning speed profile for coupling trajectory to track. Finally, according to the change of path curvature, the speed profile scheduler addresses the conflict of curvature and deceleration. Referencing to the ISO3888-2:2011, a collision avoidance scenario was design to validate the planner. The test results of ten cycles test illustrate that the planner has high enough real-time performance as mean plan time less than 100ms with success rate about 100%.
Yishan, Li, Lu, Xiong, Dequan, Zeng, Puhang, Xu, Zhuoren, Li
Research on Control Algorithm of Active Steering Control Based on the Driver Intention2019-01-506411/4/2019
Active steering technology can improve the operability of the driver by the involvement to the steering system. Driver is the major controller of the vehicle Therefore, the involvement of advanced technologies including the active steering technology shouldn’t interfere with the intention of the driver, and the driver should still have great control of the vehicle. The aim of this paper is to solve the problem of the driver’s control when the active steering system works to improve the flexibility of the low speed and the stability of the high speed, and the active steering model based on the driver’s steering intention is established. Through the CarSim simulation software, this paper adopts 9 parameters related to the vehicle steering of the DLC (Double Line Change). And PCA (Principal Component Analysis) algorithm, a tool of statistical analysis, is applied to select 4 parameters which can stand for the DLC from the 9 parameters, which makes the data processing easier. Through the 4 parameters, this model divide the driver’s steering intention into four categories (emergency steering, normal steering, turn left and turn right) having different weights of active steering angle by clustering analysis, which ensures the driver get better control to the vehicle than traditional active steering system at different steering conditions. Finally, the feasibility of this model is verified by the simulation results through the comparison with the curve of the ideal steering at DLC steering condition.
Zhang, Pengcheng, Zheng, Hongyu
Composite Steering Strategy for 4WS-4WD EV Based on Low-Speed Steering Maneuverability2019-01-505211/4/2019
A composite steering control strategy, which combines four-wheel steering (4WS) and differential steering, is proposed in this paper, to optimize steering maneuverability in the conditions where the vehicle speed is below 15 Km/h, mainly for U-turning and parking conditions. A dynamic model is developed for the steering system and the tire system. Taking different steering wheel inputs into consideration, a 4WS control strategy proportional to the front wheel steering angle is quoted to improve the steering maneuverability in the low speed conditions and guarantee the manipulability by controlling the side slip of the vehicle. Based on the 4WS system, this paper explores the possibility of further improving the low-speed maneuverability of the vehicle through differential steering. And the differential steering control strategy is developed, including four hub-motor output modes. A composite steering controller is designed based on the 4WS-4WD electric vehicle platform. Through the real vehicle calibration tests, the output torque distribution coefficient of the hub motor in the differential steering control strategy is obtained, and the composite steering control strategy optimal for maneuverability is determined by comparing the turning diameters of the low-speed tests under the four modes. The experimental results show that compared with the single 4WS system, the composite steering system has an improved effect on the low-speed maneuverability of the vehicle, which can improve the handling performance of the vehicle under the low-speed condition.
Wang, Yang Yang, Liu, Zhi Guang, Jiang, Yuan Xing
Autonomous Vehicle Engineering: November 201919AVEP1111/1/2019
Editorial Bill Visnic: Expect the unexpected The Navigator Sam Abuelsamid: Separating illusion from magic in AV deployment The Road to Automobility The era of electrified, self-driving vehicles is upon us. Engineers are key to the transformation - with much hard work still to be done. Far and Away: Remote Drivers Monitor Autonomous Vehicles Remote operators are helping autonomous shuttles and other AVs navigate through complex situations. Mapping Canada - Centimeter by Centimeter A Montreal-based company leverages artificial intelligence to take on the task of developing high-definition maps of Canada. You've Lost That Queasy Feeling… Transcontinental research aims to understand the complex nature of motion sickness to help improve the automated-vehicle experience. 3D Sonar Sees Objects Overlooked by Costlier Sensors A dream of robotic fish inspires inexpensive automated-driving sensing technology that works for the critical areas close to the vehicle. Familiarity Breeds Respect SAE surveyed participants in its recently-concluded AV 'Demo Days' ride-along program. Their responses reinforce positive perceptions about the automated-driving experience. The AV Industry Searches for a Near-Term Business Case The TechCrunch Sessions at San Jose's Mobility 2019 conference advance the dialogue for real-world business cases for AVs. Dial 'M' for Mobility: When Your Phone Becomes the Steering Wheel Tesla's controversial new Smart Summon feature raises plenty of legal-liability and regulatory questions.
Autonomous Vehicle Engineering: July 201919AVEP077/5/2019
Editorial The consolidation plot thickens The Navigator As the world turns to C-V2X, Europe picks WiFi Complexity of Autonomous-Systems Simulation, Validation Soars to the Clouds Scalable, cloud-based architectures are gaining greater acceptance for simulating and testing the myriad development aspects of automated driving. Connectivity Solutions for AVs The promises of fully connected autonomous vehicles are great, but so are the challenges. What M&E Can Teach the AV Industry About Data Media & entertainment offers important learnings on data retention, management, scalability and security. The Rodney Dangerfield of Automated-Driving Sensors Radar and lidar get all the attention, but Inertial Measurement Units are the backbone of sensor fusion. Suppliers are scrambling to make IMUs more accurate-and much less expensive. The Sense-itive Side of Autonomous Vehicles BASF is exploring how specific materials-and even paint colors and finishes-can improve the capabilities of AV sensors. German University Studying Assisted-Driving 'Handoff' Germany's Kempten University Adrive Living Lab will feature aVDS driving simulator to research ADAS stress levels. ZF's Current Work Builds for the EV, AV Future The Tier-1 giant's "vision" for improving future mobility leverages its latest safety and chassis-development innovations. Hot New 'Hands-On' Direction in ADAS Safety Research JLR researches use of steering wheel heating and cooling to reduce driver workload 5G Cellular-Enabled Test Infrastructure for AVs Launched at Millbrook Autonomous-vehicle 5G development support moves ahead at Millbrook Proving Ground in the U.K. Delivering on Autonomous Transport Einride ramps up industry partnerships and on-road demos of its all-electric self-driving truck that's missing one thing: a cab for the drivers. Driverless Ridesharing Remains in Uber's Sights Introducing a new, production-ready AV with partner Volvo, Uber's ride-share network is likely to offer self-driving vehicles on select routes.
German University Studying Assisted-Driving ‘Handoff’19AVEP07_087/1/2019
Germany's Kempten University Adrive Living Lab will feature latest aVDS driving simulator to research ADAS stress levels. Researchers at Germany's Kempten University of Applied Sciences plan to embark this year on autonomous vehicle (AV) and advanced driver-assist system (ADAS) programs that will include investigation of the safest ways to achieve handover of a vehicle when control is returned to a human driver. To do so, it is installing an AB Dynamics advanced Vehicle Driving Simulator (aVDS) that will help measure driver stress levels if the vehicle is not capable of performing a particular maneuver. The aVDS has been designed to provide high level R&D capabilities specifically for autonomous systems. The university has established its Adrive Living Lab with the third-generation simulator helping to facilitate the study of the driver's interaction with autonomous systems and their effect on drivers' perceived safety and comfort. The program has identified these two areas as the most important for consumer acceptance and enthusiasm.
Birch, Stuart
Hot New ‘Hands-On’ Direction in ADAS Safety Research19AVEP07_107/1/2019
JLR researches use of steering wheel heating and cooling to reduce driver workload Jaguar Land Rover (JLR) recently revealed novel research into a driver-safety aid: a sensory steering wheel rim that heats or cools on each side to warn of upcoming GPS-directed maneuvers-plus serves as an extra information source in low-visibility situations. The company believes it even could be used in autonomous vehicles, changing the temperature of gearshift paddles, for instance, to indicate to the driver a successfully completed SAE Level 3 “hand-over” to the vehicle's self-driving system.
Birch, Stuart
A Sensor that Fits Like a GloveTBMG-345896/1/2019
We recently had a discussion with Sri Peruvemba, VP of Strategy at BeBop Sensors (Berkeley, CA), about the technology and applications for their two-dimensional fabric sensor material. I started by asking Sri about the unusual name for the company.
A Topological Map-Based Path Coordination Strategy for Autonomous Parking2019-01-06914/2/2019
This paper proposed a path coordination strategy for autonomous parking based on independently designed parking lot topological map. The strategy merges two types of paths at the three stages of path planning, to determinate mode switching timing between low-speed automated driving and automated parking. Firstly, based on the principle that parking spaces should be parallel or vertical to a corresponding path, a topological parking lot map is designed by using the point cloud data collected by LiDAR sensor. This map is consist of road node coordinates, adjacent matrix and parking space information. Secondly, the direction and lateral distance of the parking space to the last node of global path are used to decide parking type and direction at parking planning stage. Finally, the parking space node is used to connect global path and parking path at path coordination stage. After optimizing nodes and smoothing path utilizing a fourth-degree polar-polynomial function, those two types of paths can be merged without deviation. Experiments show that the proposed topological map-based path coordination strategy can effectively generate a feasible path to guide vehicle from the drop off zone to the desired parking space. The designed controller meets real-time requirements. At the same time, continuous curvature variation of path and steady speed can improve accuracy of path tracking.
Wang, Yongsheng, Jiang, Fachao, Luo, Yugong, Qi, Yunlong, Kong, Weiwei, Yang, E-chuan
Use of Cellphones as Alternative Driver Inputs in Passenger Vehicles2019-01-12394/2/2019
Automotive drive-by-wire systems have enabled greater mobility options for individuals with physical disabilities. To further expand the driving paradigm, a need exists to consider an alternative vehicle steering mechanism to meet specific needs and constraints. In this study, a cellphone steering controller was investigated using a fixed-base driving simulator. The cellphone incorporated the direction control of the vehicle through roll motion, as well as the brake and throttle functionality through pitch motion, a design that can assist disabled drivers by excluding extensive arm and leg movements. Human test subjects evaluated the cellphone with conventional vehicle control strategy through a series of roadway maneuvers. Specifically, two distinctive driving situations were studied: a) obstacle avoidance test, and b) city road traveling test. A conventional steering wheel with self-centering force feedback tuning was used for all the driving events for comparison. Based on the lane position and vehicle response data collected, the operators’ lane tracking capability during city road traveling was slightly inferior using a cellphone compared to traditional steering wheel. However, in extreme maneuvers like obstacle avoidance and sharp right turn, the lateral tracking performance of the cellphone was up to 12.07% better than that of the steering wheel. The cellphone’s superior performance during certain vehicle maneuvers indicates its potential as an alternative steering adaptation for disabled drivers.
Wang, Chengshi, Alexander, Kim, Pidgeon, Philip, Wagner, John
Development of Hybrid Power Steering System for Commercial Vehicle2019-01-14153/25/2019
Future technology trends of commercial vehicle steering components can be divided into three types. Environment-friendly technologies for environment-related regulations such as reducing emissions and improving fuel efficiency, and technology for driving convenience using electric steering control systems, and safety technology to protect drivers, passengers, nearby vehicles and pedestrians. Heavy duty commercial vehicles require a high-power steering system that used engine-driven hydraulic pump systems (generally used min 120bar, 17Liter/min) compared to passenger cars. In recent technical trend, In order to improve fuel efficiency and realize autonomous driving technology, we designed EHPS and Motor driven electric control actuator with the same structure as C-EPS. Unlike the HPS system, the power used in the EHPS system is the motor, which rotates the gear pump to generate flow and pressure, and the steering oil is delivered to the ball nut gearbox to operate the power steering system through the pitman arm. The advantage of EHPS is that it does not use the engine drive torque, so it improves fuel efficiency by about 1%, and when the pump is connected in parallel, it can secure the flow rate to the main steering. In this process, it is difficult to realize the active autonomous driving technology of the vehicle itself through the steering angle control separately from the driver's steering intention. Therefore, the motor control device directly connected to the steering wheel is essential, and we can design the actuator system by selecting the package and the required output according to the use conditions. The required steering torque as a general auxiliary steering was about 20 Nm, and the C-EPS type actuator using a worm reducer was manufactured and the performance evaluation was carried out. In this paper, we describe the construction process of the power steering system for commercial vehicles and the design process of the components.
Lee, Byoungyun
Development of Compensation Logic for EPS in Limit Cornering Condition2019-01-14223/25/2019
This paper proposes steering compensation logic of Electric Power Steering (EPS) system in limit cornering condition. Steering wheel torque is decided by relationships between internal forces and external forces. The internal forces are steering frictions and assist force. The external forces are transferred from tire forces through kingpin axis and steering system. Kingpin moments are analyzed by using vector analysis and tire model. Relations of these forces are defined and used to explain steering disturbance by comparing simulation results and measurement data. Using these relationships, the proposed compensation logic is designed. This logic is verified by simulation models and validated in proto type vehicle.
Lee, Hanseung, Lee, Jae Kil
Optimizing Steering Column Layout and UJ Phase Angle to Enhance Vehicle Dynamics Performance2019-01-50102/5/2019
Vehicle dynamics is one of the most important vehicle attributes. It is classified into three domains, the longitudinal, vertical, and lateral dynamics. This paper focuses on optimizing the lateral vehicle dynamics which is driven by the straight ahead controllability and cornering controllability of the vehicle. One of the important parameters that dictates these sub-attributes is the steering ratio. Therefore, designing the right steering ratio is critical to meet the vehicle “specific” targets. Significant amount of work has been done by many researchers on variable steering ratio by implementing variable gear ratio (VGR) rack, active steering, and steer-by-wire systems. This paper discusses the methodology and considerations to optimize the steering ratio for a constant gear ratio rack by optimizing the steering column layout, viz., orientation and the phase angle in universal joints. A detailed analysis of steering system layout is done to optimize the steering ratio to enhance the vehicle dynamics performance. Full vehicle-level multibody dynamics (MBD) simulations are done in ADAMS® to compare the vehicle response behavior for different steering ratios in the open-loop objective tests. The Computer Aided Engineering (CAE) results show significant impact of the proposed design methodology on vehicle controllability. When the phase angle and the initial column angle are optimized for a quick on-center steering ratio, the response gains are higher, resulting in a sporty and agile feel. However, when the same vehicle is tuned for a slower on-center steering ratio, the gains are lower, resulting in a sluggish, lazy feel. This methodology can be implemented during the initial vehicle design phase to optimize vehicle performance.
Puvvula, Praneeth, Ravuri, Susheel, Dubal, Ajit, Salunkhe, Swapnil
Methodology to Determine Optimum Suspension Hard Points at an Early Design Stage for Achieving Steering Returnability in Any Vehicle2019-26-00741/9/2019
Steering returnability while driving is one of the most important parameter which affects the drive pleasure and handling of a vehicle. Steering returnability refers to the automatic returning response of the steering wheel after taking a full turn while vehicle is being steered during driving. Evaluating steering response characteristics of any vehicle in a virtual environment at early stage of a product development saves significant development time and cost. Through this paper an attempt has been made to develop a methodology for selection of suspension hard points which influences steering returnability characteristics of a vehicle at an early product design stage. Conventionally, suspension kinematic parameters such as Caster angle, Steering axis inclination (SAI), etc. are iterated during vehicle design stage to achieve desired Steering returnability. However, at times vehicle level trials indicate that increasing caster angle or SAI does not guarantee a desirable increase in steering returnability. In this new methodology a set of iterative trials are done to vary hard points (X, Y, Z co-ordinates) of Lower ball joint of an independent front suspension to create desired Jacking effect [2] or differential vertical lifting [1, 2] at front wheel end of the vehicle during steer condition to facilitate and impart self-returning motion at steering wheel. Vehicle level test results conducted on a vehicle indicates an improvement in steering returnability by around 50% with reference to the base vehicle in which hard point modifications were incorporated to validate this methodology. This methodology can be applied to other vehicles during their early design stage for faster and first time right approach.
Khanna, Nitin Kumar, Jyoti, Manjul, S, Udhayakumar, Senthi, Karthik, Desai, Sakharam
Steering Control of the Off-Highway Vehicles2019-26-01081/9/2019
Steering is integral system of any vehicle to achieve direction control. With driver’s inputs, as steering wheel is turned, the steering mechanism is operated to turn the road wheels to route the vehicle on desired path. This Paper studies the different steering architectures and the learning is applied to improve the off-highway vehicles’ steering control. Off-Highway vehicles have traditionally been using Hydrostatic Power Steering (HPS) mechanism with no feedback controls. This mechanism consists of inherent limitations to vehicle efficiency, reliability and control preciseness. In this paper, HPS is modeled using 1D simulation tools from the system parameters and derived equations. The results are plotted and discussed to acknowledge the merits and demerits of existing system which helped in proposing the alternate steering solution. Different steering architectures are evaluated and trade-off study performed to choose the Electro-Hydraulic Power Steering (EHPS) architecture. The mathematical equations behind the Electro-Hydraulic steering system are derived and couple of control strategies (like PID controller and state-feedback controller) are applied to minimize the error between commanded and actual road wheel angle. Non-linear system is simulated using different software and PID controller gains are tuned to achieve desired response. Linearized state space system is modeled to obtain the state-feedback control to operate electro-hydraulic steering valve. In the end, event triggered control is discussed to operate the steering system at desired threshold for potential energy saving.
Joshi, Bharat, Sukumar, Srikant, Jawale, Vinit, Patil, Ojas
Measurement of the loads applied to a steering system – Tie rod and steering column2018-36-02809/3/2018
Currently in the automotive industry it is indispensable the evolution of technology applied in the design and manufacturing of components, either for a specific performance improvement or even as part of a cost reduction plan. For these main reasons, it has been constantly invested in methods that may help engineers to understand the dynamic efforts to which the components are submitted. In order to determine the loads suffered by the steering system of a vehicle in motion, the Group of Automotive Technology from the Lutheran University of Brazil (also known as “GTA”) conducted tests using a front-wheel drive road vehicle with a 1.4L transverse engine. The steering column (which joins the steering wheel to the steering gearbox ) and the tie rod (which connects the steering rack to the steering knuckle) were used as elastic elements to form load cells by the attachment of resistive strain gages in a full Wheatstone bridge. The steering column was used to measure the applied torque and the tie rod to measure the resultant force. The calibration of the load cell formed by the tie rod presented linearity with R2 of 0.98 and the one formed by the steering column a R2 of 0,99. Analyzing the obtained results it is possible to infer that under standard driving conditions the highest loads occurred during hard braking combined with steering wheel maneuvers (cornering). In this condition the measured force in the tie rod achieved 300 N whilst the torque reading for the steering column was at 0.6 Nm. In a straight line the maximum resultant loads remained under 80 N and 0.3 Nm, respectively. When the vehicle is stationary and without the hydraulic assistance the torque applied to the steering column is about eight times higher in comparison to a moving vehicle (4.55 Nm and 0.55 Nm, respectively).
Gertz, L. C., Rodrigues, A. F. A., Cervieri, A., Ferri, S. D., Heidemann Jr, R., Theis, J.
Research on Variable Steering Ratio Control Strategy of Steer-by-Wire System2018-01-15838/7/2018
In this paper, the variable steering ratio control strategies under normal driving conditions and emergency driving conditions were proposed. The variable steering ratio control under normal driving conditions is based on variable yaw rate gain, and takes into account the driver’s operating habits and vehicle handling stability. The steering ratio varies with the vehicle speed and the steering wheel angle, which ensures the vehicle steering sensitivity at low speed and the steering stability at high speed. The variable steering ratio control under the emergency driving conditions is based on yaw rate dynamic feedback control, and the steering ratio varies with the vehicle movement status. We use active steering control which is based on active disturbance rejection control to achieve yaw rate dynamic feedback control, which can improve vehicle stability without affecting the longitudinal movement of vehicle. In order to verify the effectiveness of the proposed variable ratio control strategy, using CarSim and Simulink to simulate the typical driving conditions, the simulation results show that the variable steering ratio control can effectively reduce driver’s driving burden, and improve the response characteristics of the vehicle and the vehicle’s steering stability and active safety.
Wu, Yan, Wang, Lifang, Li, Fang
Analysis of Vehicle Steering Stability of Nonlinear Four Wheel Steering Based on Sliding Mode Control2018-01-15938/7/2018
Steering movement is the most basic movement of the vehicle, in the car driving process, the driver through the steering wheel has always been to control the direction of the car, in order to achieve their own driving intention. Four Wheel Steering (4WS) is an advanced vehicle control technique which can markedly improve vehicle steering characteristics. Compared with traditional front wheel steering vehicles, 4WS vehicles can steer the front wheels and the rear wheels individually for cornering, according to the vehicle motion states such as the information of vehicle speed, yaw velocity and lateral acceleration. Therefore, 4WS can enhance the handling stability and improve the active safety for vehicles. Based on the theory of Vehicle Dynamics and Sliding Mode Control, this paper investigates the following issues, Firstly, a 2DOF 2WS vehicle model is built up by using the state-space equations, which will be used to compare the 4WS vehicle model containing vehicle lateral and yaw; Secondly, based on the 4WS vehicle model with nonlinear tire lateral force characteristics, the control algorithm is designed to use feed-forward plus feed-back control framework by following the reference model. And the simulation is processed in MATLAB/Simulink and CarSim to verify the control algorithm. By comparison and analysis of the simulation results, By following the reference model, the performances of the yaw velocity and lateral acceleration responses are largely different. When set the speed at 30 km/h, 50 km/h and 80 km/h in simulations, the traditional steering stability of 2WS vehicle is not more stable than the four-wheel steering vehicle at different speeds. Consequently, the use of sliding mode control can effectively improve the steering performance of the vehicle in the steering, a good way to track the target path, and 4WS car to improve the vehicle’s handling stability.
Zhang, Jiaxu, Zheng, Hongyu, Zhao, Mengdi
Study on Lane Change Trajectory Planning Considering of Driver Characteristics2018-01-16278/7/2018
Automatic lane change of intelligent vehicles is a complex process. Besides of safety, feelings of the driver and passengers during the lane change are also very important. In this paper, a lane change trajectory planner is designed to generate an ideal collision-free trajectory to satisfy the driver’s preference. Various lane changing modes, gentle lane change, general lane change, radical lane change and personalized lane change, are designed to meet the needs of different passengers on vehicles simultaneously. In this paper, the condition of the two-lane change is studied. One vehicle is in front of the ego vehicle at the same lane and one is at the rear of the ego vehicle at the target lane. A trajectory planning method is then established based on constant speed offset and sine curve, vehicle distances and speed difference, etc. The key factors which can reflect drivers’ lane change characteristics are then acquired. Based on the key factors, lane change decision model and lane change state model are established, which can reflect drivers’ personalized lane change selection and habits based on the traffic environment. The effectiveness of lane change decision model is validated by computer simulations. In order to fit the lane change state model, a BP neural network controller is then developed. The small errors of predicted lane change time demonstrate the effectiveness of the BP neural network. Finally, lane changes with different modes are conducted in MATLAB under different vehicle distances and speed difference. Simulation results demonstrate that the proposed trajectory planner can generate collision-free trajectories and shows a good reflection of driver lane change styles. Additionally, multiple lane changing modes add the probability of practical applications. This paper can provide reference for lane change trajectory planning of intelligent vehicles.
Wang, Yang Yang, Pan, Ding, Liu, Zhiguang, Feng, Rong
Switching to comfort mode18TOFHP08_088/1/2018
Switches, knobs and touch panels evolve to reduce operator fatigue. Programmability has become a central design element for engineers tasked with making work environments more comfortable for commercial-vehicle operators. Touchscreens continue to handle more functions, while switches, knobs and joysticks are all becoming more versatile as embedded electronics turn them into multi-function controls. There's a shortage of drivers in trucking and operators in off-highway, prompting a major focus on making sure that workers in both fields stay on the job. A range of control technologies play a major role in the effort to improve comfort for those who spend long hours working in cabs.
Costlow, Terry
Optimization Control for 4WIS Electric Vehicle Based on the Coincidence Degree of Wheel Steering Centers10-02-03-00117/24/2018
The steering centers of four wheels for passenger car do not coincide, which may result in tire wear and the unharmoniously movement of the vehicle. In this article, an optimization control method for Four Wheel Independent Steering (4WIS) electric vehicle based on the coincidence degree of steering centers is proposed, to improve the driving performance. The nonlinear vehicle model of the four-wheel independent steering vehicle is established, and the formula of the wheel steering center is derived. The coincidence degree of wheel steering centers is defined as the evaluation index, to describe and evaluate the performance of the coordination for wheels’ movement. Meanwhile, the structure design of 4WIS system and the establishment of Direct-Current (DC) steering motor model are carried out, and the Model Predictive Control (MPC) controller for steering actuator is designed. The coincidence degree and related performance index for 4WIS vehicle steering system are performed as the optimization target for vehicles to achieve the optimal control by neural network predictive control algorithm. Simulations based on high-fidelity CarSim model show the effectiveness of the control approach.
Zheng, Hongyu, Yang, Shuo
Design of Adjustable Road Feeling Performance for Steering-by-Wire System10-02-02-00086/18/2018
Since steering-by-wire (SBW) system decouples mechanical linkages between front tires and the steering wheel, the road feeling characteristics of SBW system can be designed flexibly to improve the driving experience. In this article, a road feeling system with adjustable performance is proposed based on integrating the elements of the steering wheel module and the steering actuator module of SBW system. In this system, the road feeling torque consists of a main toque and a tuning torque, which are deduced by parametric method. The main torque is to feed back the tire dynamics and road properties to the driver intuitively, and the tuning torque is designed as a compensation of the main torque to tune the road feeling performance. The parameters in the formula of road feeling torque are selected properly and the driver can get the preferred road feeling performance by tuning these parameters in the formula. Next, to obtain the desired road feeling characteristics for different drivers, the sensitivity of formula parameters is analyzed quantitatively according to objective evaluation indices for on-center handling. Then, in the light of moderate type drivers, a set of tuning rules is proposed to determine specific values of parameters. Finally, contrast tests are conducted on the test bench to compare the road feeling performance of SBW test vehicle and electric power steering (EPS) test vehicle to verify the effectiveness of the proposed road feeling system in this article.
Zheng, Hongyu, Zhou, Jian
Sliding Mode Predictive Tracking Control for Electric Vehicle Using Steer-By-Wire System2018-01-06974/3/2018
Recently, a lot of electric vehicle (EV) has been developed to improve the energy consumption problem and electric power steering system has attracted the researchers’ concern. Steer-by-Wire (SbW) system is an electric steering system where the mechanical link between the steering wheel and front wheels is eliminated. Due to the absence of direct mechanical linkage, the most challenging issue is to ensure that the front wheels closely follow the driver’s command. A sliding mode predictive controller (SMPC) for Steer-by-Wire systems (SbW) is proposed to achieve a proper tracking performance. The sliding mode predictive controller has two parts: sliding mode control (SMC) and model predictive control (MPC). The SMC is applied to improve the robustness of MPC in the presence of model uncertainties while the MPC is applied to enhance the tracking performance of SMC. The simulation results and experimental results demonstrate the effectiveness of the proposed controller in steering angle tracking tasks.
Huang, Chao, Naghdy, Fazel, Du, Haiping
Design of Automatic Parallel Parking System Based on Multi-Point Preview Theory2018-01-06044/3/2018
As one of advanced driver assistance systems (ADAS), automatic parking system has great market prospect and application value. In this paper, based on an intelligent vehicle platform, an automatic parking system is designed by using multi-point preview theory. The vehicle kinematics model was established, based on Ackermann steering principle. By analyzing working conditions of parallel parking, complex constraint condition of parking trajectory is established and reference trajectory based on sine wave is proposed. In addition, combined with multi-point preview theory, the design of trajectory following controller for automatic parking is completed. The cost function is designed, which consider the trajectory following effect and the degree of easy handling. The optimization of trajectory following control is completed by using the cost function. In order to validate automatic parallel parking algorithm proposed in this paper, the simulation based on DYNA4 and real vehicle test are carried out. According to the simulation and real vehicle test results, the vehicle can well follow the reference trajectory to complete automatic parking. In the simulation, the longitudinal error and the lateral error are 4 cm and 6 cm, respectively. In the real vehicle test, longitudinal error is less than 3 cm, lateral error is less than 5 cm, and the test results meet the requirements of parallel parking.
Shi, Jiangchao, Wu, Jian, Zhu, Bing, Li, Jing, Zhao, Yang, Deng, Weiwen, He, Rui
Research of Steering Grasping to Take over Driver from System2018-01-10684/3/2018
Lane departure prevention systems are able to detect imminent departure from the road, allowing the driver to apply control to prevent lane departure. These systems possess enormous potential to reduce the number of accidents resulting from road departure, but their effectiveness is highly reliant on their level of acceptance by drivers. The effectiveness of the systems will depend on when they are providing driving assistance, what level of laxness in terms of maintaining contact with the steering wheel is allowed on the part of the driver, and what level of assistance the system provides. This paper will discuss research on the minimum necessary contact and contact strength with the steering wheel on the part of the driver when a lane departure prevention system is in operation. Using a six-axis driving simulator employing an actual vehicle, the research conducted tests involving 22 test subjects, and studied the relationship between the status of the driver’s contact with the steering wheel and vehicle behavior when the system failed. As a result of simulation, when the driver had relinquished steering control and the vehicle was self-steering on the curve, contact of even one finger with the steering wheel made the reaction time faster.
Odate, Shotaro, Fujimaki, Takeshi, Sakamoto, Naohiro
Driver Response Time to Cyclist Path Intrusions2018-01-05314/3/2018
Motor vehicle crashes with cyclists are on the rise, with a six percent increase in fatal crashes from 2006 to 2015 in the USA. Although some research exists on the response time of drivers to some types of path intrusions, data on the perception-response of through drivers to cyclists who fail to stop at a stop sign, and ride into the path of the vehicle has not been researched. The purpose of this study was to quantify the Driver Response Time (DRT) to a cyclist that intrudes perpendicularly in front of a through vehicle at an intersection where the driver has the right-of-way. The DRT was measured from when the cyclist is positioned at the stop sign until the driver reacts, whether by touching the brake pedal, swerving (steering wheel angle change of at least 2 degrees), accelerating, or a combination of those responses. 26 (NFemale = 13; NMale = 13) university aged licensed volunteer drivers participated in the study conducted at the University of Guelph Driving Research in Virtual Environments (DRiVE) lab using an Oktal complete vehicle driving simulator. After a brief practice drive to acclimatize to the virtual environment, participants completed the approximately 10 minute experiment drive during which the cyclist hazard was presented. About one quarter of drivers crashed into the cyclist, with a mean time-to-impact of 3.26 seconds. There were no gender differences in terms of DRT or collision rates.
Toxopeus, Ryan, Attalla, Shady, Kodsi, Sam, Oliver, Michele
Steering Column Slip Endurance Test & Rig Development2018-01-01254/3/2018
In the emerging commercial vehicle sector, it is very essential to give a product to customer, which is very reliable and less prone to the failures to make the product successful in the market. In order to make it possible, the product is to be validated to replicate the exact field conditions, where it is going to be operated. Lab testing plays a vital role in reproducing the field conditions in order to reduce the lead time in overall product life cycle development process. This paper deals with the design and fabrication of the steering column slip endurance test rig. This rig is capable of generating wear on the steering column splines coating which predominantly leads to failure of steering column. The data acquired from Proving Ground (PG) was analyzed and block cycles were generated with help of data analyzing tools. Those block cycles were run with the help of this rig it consists of Variable Frequency Drive (VFD) to change the velocity of steering column, and torque applied on component to reproduce field conditions.
G, Manthiramoorthy, Rajendran, Manoj Kumar, Siva Kumar, Natarajan, Subramanian, Deepak Anand, V, Srinivasa Chandra
Evaluation of Alternative Steering Devices with Adjustable Haptic Feedback for Semi-Autonomous and Autonomous Vehicles2018-01-05724/3/2018
Emerging autonomous driving technologies, with emergency navigating capabilities, necessitates innovative vehicle steering methods for operators during unanticipated scenarios. A reconfigurable “plug and play” steering system paradigm enables lateral control from any seating position in the vehicle’s interior. When required, drivers may access a stowed steering input device, establish communications with the vehicle steering subsystem, and provide direct wheel commands. Accordingly, the provision of haptic steering cues and lane keeping assistance to navigate roadways will be helpful. In this study, various steering devices have been investigated which offer reconfigurability and haptic feedback to create a flexible driving environment. A joystick and a robotic arm that offer multiple degrees of freedom were compared to a conventional steering wheel. To evaluate the concept, human test subjects interacted with the experimental system featuring a driving simulator with target hardware, and completed post-test questionnaires. Based on the data collected, drivers’ lane keeping performance was superior using a haptic robotic arm with haptic feedback to the joystick and steering wheel with an improvement of up to 70.18% during extreme maneuvers. Haptic feedback, with a lane keeping algorithm, can assist the operator in steering the vehicle given the likely deterioration of driving skills when autonomous vehicles become prevalent.
Wang, Chengshi, Wang, Yue, Wagner, John R.
Control of Steer by Wire System for Reference Steering Wheel Torque Tracking and Return-Ability2018-01-05664/3/2018
This paper proposes a torque tracking algorithm via steer by wire to achieve the target steering feel and proposed a modified friction model to obtain return-ability. A three dimensional reference steering wheel torque map is designed using the measurement data of the steering characteristics of the target vehicle at a transition test and a weave test. In order to track the reference steering wheel torque, a sliding mode control is used in the tracking algorithm. In addition, to achieve return-ability, the modified friction model for steer by wire is used instead of the friction model defined in the reference steering wheel torque map. The modified friction model is composed of various models according to the angular velocity. The angular velocity and the angular acceleration used in the control algorithm are estimated using a kalman filter. A motor is used as the actuators to generate the targeted steering feel and the torque angle sensor (TAS) is used to measure the steering wheel torque and the steering wheel angle. Using the computer simulations, the return-ability of the proposed controller was evaluated with the return test and the tracking performance of the proposed controller was evaluated with the weave test and transition test. By using this proposed control algorithm in steer by wire system, the steering feel close to that of a conventional motor driven steer system has been successful obtained and return-ability has been achieved.
Lee, Jaepoong, kyongsu, Yi, Kim, Kwangil, Lee, Byungrim, Lee, Dongpil, Jang, Bongchoon, Chang, Sehyun
2021-12-29.TEST Development of Autonomous Driving System Using GNSS and High Definition Map2018-01-00364/3/2018
Recently, development of vehicle control system targeting Full Driving Automation (autonomous driving level 5) has advanced. Some applications of autonomous driving systems like the Lane Keeping Assist system (LKA) and Auto Lane Change system (ALC) (autonomous driving level 1-3) have been put on the market. However, the conventional system using information from front camera, it is difficult to operate in some situations. For example the road that no line, large curvature and number of lane increases or decreases. We propose an autonomous driving system using high accuracy vehicle position estimation technology and a high definition map. An LKA system calculates the target steering wheel angle based on both vehicle position information from the Global Navigation Satellite System (GNSS) and the target lane of high the definition map, according to the method of front gaze driver model. Then, the system controls steering the wheel angle by Electric Power Steering (EPS). In the case of ALC, a target lane-change path is generated based on information of the vehicle’s own lane and the next one. The proposed system solved the problem of the conventional method. Moreover, the developed method can operate more smoothly than the conventional one. Finally, we demonstrate that the proposed system enables the actual vehicle to operate LKA and ALC in the merged road of a test tracks.
Takeuchi, Yu, Hideyuki, Tanaka, Kazuo, Hitosugi, Tomoki, Uno
2019 XC40 showcases Volvo's new CMA platform18AUTP02_142/1/2018
While some larger OEMs have lagged behind the bulging crossover curve, Volvo is launching its third in two years. The 2019 XC40, Volvo's first premium compact CUV and its first global 40-series vehicle, is easily identified as a family member. Volvo calls it a design “cousin” (not a sibling) to its larger XC60 and XC90 stablemates, with its own character. It is also the Swedish maker's first vehicle on the new Compact Modular Architecture (CMA) platform shared with Chinese parent Geely Automobile and the first available through an all-inclusive “Care by Volvo” subscription as an alternative to a traditional sale or lease.
Witzenburg, Gary
700 MILES, hands-free!17AUTP11_0111/1/2017
GM's Super Cruise turns Cadillac drivers into passengers in a well-engineered first step toward greater vehicle autonomy. Two sunny days in late September, a state-of-the-art luxury sedan, and good company make for a potentially great road trip. But this one was special. “Pretty remarkable that we've already driven about 500 miles without either of us touching the steering wheel; I'm impressed,” I noted to co-driver Sam Abuelsamid, as we headed southbound from Chicago, on Interstate 57 in Illinois.
Brooke, Lindsay
Cadillac plugs in CT6 for high-value efficiency17AUTP10_1510/1/2017
The badge on the decklid reads ‘2.0E’, with no giveaway that the 2018 Cadillac CT6 we're driving is a plug-in hybrid. Perhaps a more appropriate nameplate should be CT6 NEV, because this impressively engaging and efficient luxury sedan is mostly aimed at China's burgeoning New Energy Vehicle market. In fact, the plug-in version is assembled only in Shanghai and is exported to the U.S. Initial stateside volumes will be only 1000 units/year. It would not be surprising to find more American customers who see the CT6 plug-in's almost ideal balance of EV range (31 mi in optimal thermal conditions), EV top speed (78 mph); acceleration (0 to 60 mph in 5.2 s); EPA rated efficiency (62 mpg-e); total range (442 mi), top speed (150 mph) and retail price ($75,095) as adding up to a compelling value proposition.
Brooke, Lindsay
Voltage spike at 2017 Frankfurt auto show17AUTP10_1310/1/2017
Judging by the wares on display at September's 2017 Frankfurt auto show, electrification suddenly is the watchword in Germany-or the watchword, at least, for some indeterminate date in the future. Because none attending the show could escape the irony that while nearly every major German manufacturer's Frankfurt effort centered on an electric vehicle, many of the show's current or near-future production models remained resolutely diesel-powered. Audi's AIcon (combining “artificial intelligence” and “concept”) was the company's vision of SAE Level 5 autonomy-it has no steering wheel or pedals. The EV architecture permits generous interior space for four passengers, Audi said, as did the concept car's 136.6-in (3470-mm) wheelbase and 82.6-in (2098-mm) width. Audi said projected power from the solid-state batteries (another buzz technology cropping up at Frankfurt) is 260 kW (248 hp) and 405 lb·ft (549 N·m) dispersed to an electric motor driving each wheel. The German makers also were touting new 800-volt charging technology and Audi said using such a system would deliver 80% of the AIcon's 400 mi-plus driving range in just 30 minutes.
Visnic, Bill
Precise Steering Angle Control of Lane Change Assist System2017-01-20029/23/2017
After obtaining the optimal trajectory through the lane change decision and trajectory planning, the last key technology for the automatic lane change assist system is to carry out the precise and rapid steering actuation according to the front wheel angle demand. Therefore, an automatic lane change system model including a BLDCM (brushless DC motor) model, a steering system model and a vehicle dynamics model is first established in this paper. Electromagnetic characteristics of the motor, the moment of the inertia and viscous friction etc. are considered in these models. Then, a SMC (Sliding Mode Control) algorithm for the steering system is designed to follow the steering angle input. The control torque of the steering motor is obtained through the system model according to steering angle demand. After that, the control current is calculated considering of electromagnetic characteristics of the BLDCM. Debugging and optimization of the control algorithm are done through simulations. Also, different steering input and uncertain disturbance torque are successively loaded on the simulation model to test the tracking performance and robustness of the control algorithm. Simulation results are compared with the PID’s and show that under different steering inputs, the steering system with the proposed controller manifests a better tracking performance. Even if large parameter uncertainties are taken into consideration, tracking error will not be enlarged obviously, which indicates that the SMC has good robustness. These results can provide reference for precise steering angle control of the automatic lane change assist system by considering of different parts of the steering system, steering motor, steering transmission linkage, and steered wheels.
Wang, Yang Yang, Chen, Guangda, Ao, Xuanjing, Fan, Shuhao, Mei, Han, Li, Wei
Path-Tracking Controller Design for a 4WIS and 4WID Electric Vehicle with Steer-by-Wire System2017-01-19549/23/2017
Path tracking is the rudimentary capability and primary task for autonomous ground vehicles (AGVs). In this paper, a novel four-wheel-independent-steering (4WIS) and four-wheel-independent-drive (4WID) electric vehicle (EV) is proposed which is equipped with steer-by-wire (SBW) system. For path-tracking controller design, the nonlinear vehicle model with 2 degrees of freedom (DOF) is built utilizing the nonlinear Dugoff tire model. The nonlinear dynamic model of SBW system is conducted as well considering the external disturbances. As to the path-tracking controller design, an integrated four-wheel steering (4WS) and direct yaw-moment control (DYC) system is designed based on the model predictive control (MPC) algorithm to track the target path described by desired yaw angle and lateral displacement. Then, the fast terminal sliding mode controller (FTSMC) is proposed for the SBW system to suppress disturbances. The control allocation algorithm of DYC is realized by weighted least square (WLS). To evaluate the performance of the designed controller, numerical simulations of two maneuvers are carried out using a high-fidelity and full-vehicle model via CarSim-Simulink platform. Simulation results show that the integrated 4WS+DYC controller has better path-tracking performance than other controllers, and it has strong robust performance against parametric perturbations, i.e. the road adhesion coefficient and vehicle longitudinal velocity.
Hang, Peng, Chen, Xinbo, Luo, Fengmei
Personalized Controller Design for Electric Power Steering System Based on Driver Behavior07-11-02-00089/23/2017
Electric power steering (EPS) system is a kind of dynamic control system for vehicle steering, which can amplify the driver steering torque inputs to the vehicle to improve steering comfortable and performance, but the present EPS can’t cater to the driving habits of different people. In this article, a personalized EPS controller is designed based on the driver behavior, which combines real-time driver behavior identification strategy with personalized assistance characteristic. Firstly, the driver behavior data acquisition system is designed and established, based on which, the input data of different kinds of drivers along with vehicle signals are collected under typical working conditions, then the identification of driver behavior online is realized using the BP neural network. Secondly, the personalized assistance characteristic curve is selected according to the identification results, and the close loop proportional-integral-derivative (PID) control strategies and pulse width modulation (PWM) method are adopted to control the target current of the motor of the EPS system. Finally, the co-simulation of Simulink and Carsim are carried out, and the results show that personalized electric power steering system based on driver behavior can adjust power-assisted characteristics timely, and it can match the driver usage modes automatically and meet the drivers’ steering power demands better.
Zhu, Bing, Yan, Shude, Zhao, Jian, Deng, Weiwen
Parameter Sensitivity Analysis of a Light Duty Truck Steering Returnability Performance2017-01-04283/28/2017
Steering returnability is an important index for evaluating vehicle handling performance. A systematic method is presented in this paper to reduce the high yaw rate residue and the steering response time for a light duty truck in the steering return test. The vehicle multibody model is established in ADAMS, which takes into consideration of the frictional loss torque and hydraulically assisted steering property in the steering mechanism, since the friction, which exists in steering column, spherical joint, steering universal joint, and steering gear, plays an important role in vehicle returnability performance. The accuracy of the vehicle model is validated by road test and the key parameters are determined by executing the sensitivity analysis, which shows the effect of each design parameter upon returnability performance. Analysis results indicate that the key parameters are the steering gear internal fluid resistance, mechanical friction, the caster angle and the torsion bar stiffness, which greatly influence the yaw rate residue and steering response time.
Lv, Tianqi, Wang, Yan, Feng, Xingxing, Zhang, Yunqing
Impact of Pre-Study Exploration on System Usability Scale and Task Success Rates for Automotive Interfaces2017-01-13853/28/2017
Measurement of usability with the System Usability Scale (SUS) is successfully applied to products in many industries. The benefit of any measurement scale, however, is limited by the repeatability of the associated testing process. For SUS, these factors can include sample size, study protocol, previous experience, and pre study exposure to the system being tested. Differences in user exposure can influence the usability assessment of interfaces which could affect the validity of SUS scores. A customer clinic was conducted on a steering wheel/instrument cluster and a center display screen, to see the difference in SUS scores of participants with “Free Exploration (participant had a few minutes to interact with the system)”, “Guided Exploration (participant was given a couple of tasks prior to the study)”, “No Exploration (no interaction prior to the study)” and “Repeated task Exploration (tasks were asked again after the no exploration phase concluded)” in a between subject design study. All four scenarios were analyzed for their impact on SUS score, task success rates and adjective rating. Under the “No Exploration” test method the estimates of mean SUS score, adjective rating and task success rates are reliable and repeatable with a good correlation to external quality metrics.
Chandran, Satheesh Kumar, Forbes, James, Bittick, Carrie, Allanson, Kathleen, Erupaka, Santosh, Brinda, Fnu
Multisensory Contributions to Perceived Quality and Authenticity of Materials for the Vehicle Interior2017-01-04943/28/2017
Material authenticity is an important factor for appearance and perceived quality of the vehicle interior. The term authenticity implies ambivalence: For the product designer, it means identification and trueness of the origin of the material. The customers, however, can only access information on the nature of the materials via their own perception of surface features. Thus, the intended authenticity of a material always needs to be conveyed by its surface. Specific cases illustrate the context: 1. The customer touches a part of known matter, but various layers prevent from directly touching the natural material: e.g. leather at the steering wheel, applications of wood. 2. Perception of a thin surface layer indicates authentic material, which is not fulfilled by the whole part: e.g. plastic parts plated with metal. 3. A part consists of authentic material, but newly composed, so that it is not easily identified, such as recycled materials, e.g. leather fiber layers for seats. Optimization of the perceivable authenticity is always a multi-sensory task. Customers see and touch materials in the show room. Sound is usually generated by touching surfaces. Smell is important for natural materials, like leather. Even if the material is only observed visually, its appearance points towards tactile features, like softness, roughness, etc. Beside general considerations, multi-sensory perception of leather and vinyl materials as well as haptic appearance of thin metal layers is described in detail. An innovative method for measurement of the contact temperature is introduced, which helps to evaluate the materials potential to provide authentic “metal feel”.
Haverkamp, Michael Christian, Moos, Anja
A Model Based Approach for Electric Steering Tuning to Meet Vehicle Steering Performance Targets2017-01-14933/28/2017
Subjective steering feel tuning and objective verification tests are conducted on vehicle prototypes that are a subset of the total number of buildable combinations of body style, drivetrain and tires. Limited development time, high prototype vehicle cost, and hence limited number of available prototypes are factors that affect the ability to tune and verify all the possible configurations. A new model-based process and a toolset have been developed to enhance the existing steering development process such that steering tuning efficiency and performance robustness can be improved. The innovative method utilizes the existing vehicle dynamics simulation and/or physical test data in conjunction with steering system control models, and provides users with simple interfaces which can be used by either CAE or development engineers to perform virtual tuning of the vehicle steering feel to meet performance targets. The process can be used not only in early phases of vehicle programs before prototypes are available, but also in parallel to prototype tuning for objectively evaluating vehicle configurations that might otherwise be only assessed subjectively due to limited prototype availability.
Wang, Dexin, Mao, Yiqin, Drotar, Timothy, Esser, Frank, van Dijk, Hessel, Paas, Michel
Chicago fire: Dodge puts 375-hp Hemi V8 in Durango SRT17AUTP03_103/1/2017
“Performance” SUVs are not a new concept, but FCA's Dodge brand opens a new niche-within-a-niche with the unveiling of the 2018 Durango SRT at the 2017 Chicago auto show, calling it “the fastest SUV in its class.” Dodge officials didn't directly say just who's asking for a grocery-getter SUV with 475 hp (354 kW) and 470 lb·ft (637 N·m) from a 6.4-L (or, more historically relevant, 392-in3) V8 that enables cutting a 12.9-s quarter mile time, but the Durango SRT will be in showrooms for that buyer starting in the fourth quarter. Some of the work of adapting the 6.4-L Hemi for the Durango already was done: it is the same iron-block, pushrod V8 with a 10.9:1 compression ratio that appears in the Jeep Grand Cherokee SRT, which shares its architecture with the Durango.
Visnic, Bill
I.D. Buzz: VW's latest future-look Microbus17AUTP02_142/1/2017
It's a VW Microbus for future generations, an electric van capable of fully autonomous driving. But at this point, it's only a concept. “We want to re-ignite America's love for Volkswagen. And we are fully committed to the future of mobility-smart, sustainable, affordable-that is the new Volkswagen,” proclaimed Dr. Herbert Diess, Chairman of the Board of Management for the Volkswagen Brand.
Buchholz, Kami
Self-Propelled Sweepers and Scrubbers Steering Requirements Single-Circuit Hydraulic Servo-Assisted SystemsJ1790_201612 (Historical)12/9/2016
The SAE Standard applies to self-propelled, driver-operated sweepers and scrubbers as defined in SAE J2130-1 and SAE J2130-2.
MTC2, Sweeper, Cleaner, and Machinery
Volvo, Uber share the ride to safety with autonomy16AUTP10_0710/1/2016
The news that Volvo Cars, renowned for its safety focus, and ride-sharing company Uber, are working together to develop next generation autonomous driving (AD) cars eventually reaching full SAE Level-5 standard (no steering wheel or controls), may bring comfort to those who are scared, skeptical or just scorn the advent of being driven by such radical robotics. But this latest development sees a further step to AD being taken in parallel with Volvo's avowed intent that no one traveling in its new models from 2020 onwards will be killed or seriously injured. That bold statement was first uttered in 2007, presaging the introduction or development of a plethora of safety features that the automaker believes will enable it to achieve its target.
Birch, Stuart
Items per page:
1 – 50 of 368