Browse Topic: Steering systems

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Extraordinary and Special Purpose Landing Gear SystemsAIR4846B (Current)11/11/2025
A landing gear system comprises the most compelling assembly of engineering skills. Its importance to the successful design of an aircraft can be favorably compared with that of the aircraft's wings and engines. A landing gear system consists of several different engineering disciplines, and is continually in the public eye especially with regard to safety. The primary objective of AIR4846 is to present a record of a variety of interesting gears, gear/aircraft systems and patents, and to discuss wherever possible the lessons learned, and the reasons for the design. Thus, the document is not only a historical account, but a means of recording technical knowledge for the practical benefit of future landing gear designers. Commendable efforts have been made over the years by several individuals to make such recordings, and AIR4846 will make continual reference to them. This applies to all books, papers, or specifications that have the approval of the SAE A 5 Committee. AIR4846 also accepts the premise that an essential aircraft requirement can often justify a gears' complexity and consequent weight. However, the document's purpose is not to recommend, but to provide reliable, authenticated information. Hence, the gear designer would be better equipped to adjudicate trade studies rationally, while not restricting his/her innovative skills. Each gear design feature will be associated with as many aircraft examples as possible, and every effort will be made to ensure accuracy, authenticity, and detail clarity. Section 2 of this document describes the features of landing gear which are addressed in the specific descriptions of various landing gears (Category A). Also, special types of landing gear are categorized as Category B.
A-5B Gears, Struts and Couplings CommitteeNEW
Optimal Approaches of Unmanned Helicopters in Wind-Sensitive Maritime OperationsF-0081-2025-02485/20/2025
Helicopters' Vertical Take-Off and Landing (VTOL) capabilities are essential for maritime operations, especially for small-deck naval vessels. Unmanned Aerial Vehicles (UAVs) offer a cheaper, expendable, and efficient alternative for certain tasks, such as reducing pilot risk and lowering fuel consumption. While the procedures to approach and land on (moving) ships are standardized and bound to established operational limits in the case of crewed helicopters, UAVs lack such guidelines. This study investigates optimal rotary-wing UAV approach trajectories to a moving ship, for varying wind conditions and relative initial positions, and for different objectives. The goal is to provide preliminary guidelines for maritime UAV recovery operations, and a preliminary estimation of performance-based operational limits. The optimal trajectories are obtained using a global path-performance optimization framework based on Optimal Control Theory. The trajectories are compared to each other and to reference cases using the Longest Common SubSequence (LCSS) similarity measure, revealing how the unmanned helicopter adjusts its path to exploit the wind direction and profile for more efficient ground speeds. The violation of performance and/or geometric constraints is used to preliminarily indicate the presence of operational boundaries. The control effort and energy consumption are used to identify optimal starting positions for the helicopter approach phase for a given wind profile and intensity.
Pavel, Marilena, Voskuijl, Mark, Varriale, Carmine, Zilver, Damy
UAVs Swarm Distributed Control based on Artificial Potential FieldF-0081-2025-03805/20/2025
This paper presents a distributed algorithm to track a desired target while fostering the emergence of a swarm formation and providing obstacle avoidance capability to deal with unknown scenarios. The proposed approach is based on the merge between a Flight Management System for global path planning and the definition of virtual forces through a custom Artificial Potential Field to prevent drones collisions between each other, with external objects and to provide cohesion of the swarm configuration. Each drone independently computes its global route and adjusts its path based on an optimal control action to minimize a potential energy function induced by its neighbors and obstacles. This approach results in a high cost-effective strategy to enhance UAVs autonomy level by managing a large group of drones, guaranteeing a low cost per unit thanks to the low computational effort and low-budget sensor suit while providing all the capabilities to accomplish the desired mission.
Cadeddu, Davide
A Maneuver Control System Enabling Simplified Vehicle Operations and Tactical Maneuvering for a Tilt-Wing AircraftF-0081-2025-04065/20/2025
Complex vertical takeoff and landing configurations that transition between vertical and forward flight modes necessitate advanced flight control systems to substantially reduce pilot workload. Prior work demonstrated the Trajectory Control System, a flight control architecture that enables such Simplified Vehicle Operations. However, there may also be scenarios or applications that require more aggressive maneuvering with rates and attitudes that exceed the nominal envelope. This paper demonstrates a flight control architecture with a middle-loop that harmonizes the Trajectory Control System with a Tactical Maneuvering System that enables more aggressive maneuvering, with seamless in-flight transitions between the two. In both cases, the middle-loop is linked with an explicit model-following inner-loop control system. Flight test results for the Trajectory Control System and maneuver simulation results for the Tactical Maneuvering System are shown for a subscale tilt-wing configuration.
Chakraborty, Imon, Kunwar, Bikash, Schmidt, Peter
Flight Testing of Explicit Model-Following Trajectory Control System for Lift-Plus-Cruise and Tilt-Wing ConfigurationsF-0080-2024-13065/7/2024
The ongoing development of numerous novel vertical takeoff and landing configurations necessitates flight control system design that enables the Simplified Vehicle Operations paradigm. This paper shows flight test results for one subscale lift-plus-cruise and one tilt-wing configuration employing such a flight control system architecture. Pilot inceptor inputs are used to synthesize trajectory commands that are processed by a full-envelope trajectory control system that generates propulsor thrust commands, a wing angle command, and attitude and rate commands for linear quadratic integral and explicit model-following inner-loop control systems. Commonalities and differences in the flight control implementation for the two configurations are highlighted. Results are shown for both configurations subject in manually piloted flights. The flight test results demonstrate that the flight control system designs allow a minimally trained operator to operate the two flight test vehicles safely and proficiently.
Comer, Anthony, Taheri, Ehsan, Kovryzhenko, Yevhenii, Kunwar, Bikash, Putra, Stefanus, Bhandari, Rajan, Chakraborty, Imon
An Offline Path Planner for Full Scale HelicoptersF-0080-2024-12475/7/2024
In this paper, an offline path planning module, which is capable of generating dynamically feasible 3D trajectories for a class of Vertical Takeoff and Landing (VTOL) vehicles is presented. Input to the module is a flight plan defined by a set of way-points and its output is twofold: first, it produces an improved flight plan introducing additional waypoints and speed changes based on the heuristics and dynamical constraints of the vehicle. This new plan facilitates the pilot by providing information on specific locations and changes of the original flight path. Second, it generates a set of reference points, which can be used as the initial set of inputs for an online reactive trajectory optimization algorithm. The proposed development is capable of processing both climbs and descents as well as both fly-by and flyover waypoints, and speed changes in between those way-points. The module was also designed to capture the pilot's perspective of an abstract way-point mission. NRC has implemented a nominal Nonlinear Model Predictive Control (NMPC) based online planner using the reference trajectories generated by the proposed offline planning module successfully. The generated improved mission was implemented on a simulator having Bell 412 flight dynamics and promising results were obtained.
Jayasiri, Awantha, Jennings, Sion, Alexander, Marc, Ellis, Kris, Gowanlock, Derek, Gubbels, Arthur
Optimizing Explicit Model-Following Trajectory Control Laws for a Vectored Thrust ConfigurationF-0080-2024-12775/7/2024
The complex vertical takeoff and landing configurations currently under development necessitate flight control system design that enables substantial reductions of pilot workload through Simplified Vehicle Operations. This paper shows optimization and simulation of such a flight control system architecture for a subscale vectored thrust aircraft configuration. A full-envelope Trajectory Control System for longitudinal dynamics was coupled with explicit model-following inner-loop controllers, and a scheduled control allocation logic. Control system parameters were determined using a genetic algorithm optimization scheme subject to dynamic stability, robustness, and control responsiveness constraints. Flight simulation results for a series of representative maneuvers including departure and arrival transitions and forward flight maneuvers are presented to demonstrate the effectiveness of the proposed flight control system architecture.
Chakraborty, Imon, Comer, Anthony
Manned-Unmanned Teaming Applied To HEMS Missions: A Path Planning Approach Based On The Pilot's Workload AssessmentF-0080-2024-12135/7/2024
This paper presents a path planning concept based on the Manned-Unmanned Teaming (MUM-T) between the helicopter and a drone. The drone flies ahead of the helicopter to detect possible unexpected obstacles in the mission area and sends the data to the helicopter. The path of the helicopter is automatically replanned to avoid the meteorological and physical obstacles detected by the drone. The path planning is based on the Rapidly-exploring Random Tree* (RRT*) and the Bidirectional Rapidly-exploring Random Tree (BiRRT) algorithms. The reference trajectory is planned by means of the RRT* algorithm and the replanning is performed with the BiRRT. The node connection is realized with the Dubins curves, that force the path to comply with the prescribed limitations on the helicopter's roll angle and flight path angle. The Savitzky-Golay filter is used to smooth the trajectory achieving curvature continuity. A closed-loop simulation model containing the dynamics of the pilot is used to evaluate the feasibility of a candidate trajectory basing on the pilot's workload. The pilot's dynamics is modeled through the frequency-based multi-axis Hess model. A workload assessment method is proposed basing on the aggression factor, which depends on the time histories of the control inputs. The workload quantitative assessment is carried out by comparison with the aggression factor on a "simple" manoeuvre, the spiral.
Roncolini, Francesca, Quaranta, Giuseppe
Model Predictive Path Integral Approach for Trajectory Guidance of Rotorcraft Shipboard LandingF-0074-2018-127805/7/2024
ABSTRACT Rotorcraft shipboard landing continues to be challenging due to increased pilot workload in dealing with effects of ship air wake turbulence on vehicle motion and random ship motion. Some of the recent work has proposed a pilot assist function for reduced pilot workload using model predictive control methods. This paper explores the use of a recently developed Model Predictive Path Integral (MPPI) method based on a stochastic optimal control framework for trajectory guidance solution to the shipboard landing problem. First, a proof-of-concept study is presented by applying the MPPI method to a simple point mass approximation of helicopter dynamics represented in the form of a first-order command acceleration model, representative of helicopter trajectory motion in the vertical plane. Next, the MPPI method is used in conjunction with a six degrees-of-freedom linear model of a helicopter in order to gain further insight into the applicability of the MPPI framework to the rotorcraft shipboard landing problem. The paper concludes with key observations and inferences gained in this study.
Prasad, J.V.R., Comandur, Vinodhini, Walters, Robert, Guerrero, David
Emergency Obstacle Avoidance Trajectory Planning Method of Intelligent Vehicles Based on Improved Hybrid A*10-08-01-000111/14/2023
Abstract In this article, we present a spatiotemporal trajectory planning algorithm for emergency obstacle avoidance. Utilizing obstacle and driving environment data from the sensing module, we construct a 3D spatiotemporal grid map. This informs our improved hybrid A* algorithm, which identifies collision-safe, dynamically feasible trajectories. The traditional hybrid A* algorithm is enhanced in three significant ways to make the search practical and feasible: (1) optimizing search efficiency with motion primitives based on child node acceleration, (2) integrating collision risk into the heuristic function to reduce ineffective node exploration, and (3) introducing a One-Shot search based on the Optimal Boundary Value Problem (OBVP) to improve goal state searches. Finally, the algorithm is tested in two scenarios: (1) a vehicle cut-in from an adjacent lane and (2) a pedestrian crossing. Simulation results indicate that our proposed emergency obstacle avoidance trajectory planning method can efficiently devise trajectories that not only circumvent obstacles safely and adhere to vehicle dynamics constraints, but also meet the real-time demands of emergency obstacle avoidance trajectory planning.
Chen, Guoying, Yao, Jun, Gao, Zhenhai, Gao, Zheng, Zhao, Xuanming, Xu, Nan, Hua, Min
Experimental Evaluation of Panel-Method-Based Path Planning for eVTOL in A Scaled Urban EnvironmentF-0078-2022-175365/10/2022
ABSTRACT
Bilgin, Zeynep, Yavrucuk,  Ilkay, Bronz, Murat
Acceleration of Heuristic Motion Planning for Unmanned Aerial VehiclesF-0078-2022-176415/10/2022
ABSTRACT
Thelasingha, Neelanga, Nallan,  Kaushik, Julius, A., Mishra,  Sandipan
Transition Trajectory Planning and Control for Quadrotor Biplanes in Obstacle Cluttered EnvironmentsF-0078-2022-176395/10/2022
ABSTRACT
Reddinger, Jean-Paul, McIntosh, Kristoff, Kim,  Jae, Mishra,  Sandipan
Steering Control Systems - Heavy TrucksJ2425_202111 (Current)11/9/2021
This SAE Recommended Practice describes a laboratory test procedure and requirements for evaluating the characteristics of heavy-truck steering control systems under simulated driver impact conditions, as well as driver entry/egress conditions. The test procedure employs a torso-shaped body block that is impacted against the steering wheel.
Truck Crashworthiness Committee
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
Optimal Trajectory Generation for Transitioning Quadrotor Biplane Tailsitter using Differential FlatnessF-0077-2021-168585/10/2021
ABSTRACT
Reddinger, Jean, McIntosh, Kristoff, Mishra,  Sandipan, Zhao,  Di
Panel-Method-Based Path Planning for eVTOL in Urban EnvironmentF-0077-2021-167785/10/2021
ABSTRACT
Unal, Zeynep, Yavrucuk, Ilkay
An Online Coverage Path Planning Method for Sweeper Trucks in Dynamic Environments2021-01-00954/6/2021
In this paper, a novel online coverage path planning (CPP) method for autonomous sweeper trucks in closed areas is proposed. This method can efficiently generate executable paths for sweeper trucks that cover all feasible uncleaned areas without getting tracked in dead-end, i.e., no backward behaviors required and avoid dynamic obstacles. To reach that end, a modified biological inspired neuron network method considering vehicle constrains is developed, where the dynamic of each neuron is determined by the shunting function. The path will be iteratively generated based on local neuron dynamics. In order to avoid dead-end, a detour algorithm combing with back iteration is introduced to search the nearest uncleaned area that can be reached within vehicle constrains. The proposed method is empirically approved to be computationally efficient and adaptive to maps with arbitrary shapes. The feasibility of generated paths is validated in simulations, where the pure pursuit method is applied to achieve path following. The truck model in the simulation achieves 100% coverage with reasonable cross-track errors.
Zhang, Weiyang, Sun, Yong, Yu, Wenbo, XU, MENG
Time-Optimal Trajectory Planning for Multi-Vehicle Coordinated Left-Turn Condition at an Unsignalized Intersection2021-01-00964/6/2021
The left-turn condition is the most complicated one at the unsignalized intersection, which is one of the key factors that affect traffic safety and efficiency. To solve this problem, this study proposes a distributed trajectory optimization framework based on the Gauss pseudospectral method (GPM). First, a circular obstacle based on the road size is constructed to replace the actual path constraint. The movement of obstacle is used for iterative calculations, and the trajectory of the left-turn vehicle is approached to the theoretical path. Then, for the multi-vehicle coordinated condition, the collision free constraints between vehicles is added to the optimization framework several times. In addition, the previous calculation result is used as the initial guess solution for the next calculation until all constraints are set. The simulation results show that the circular obstacle is effective and convenient, and the trajectory of a single vehicle is close to the actual driving state due to the good restraint effect. The iterative method of gradually increasing constraints can effectively avoid calculation failures caused by complex conditions, and the real-time performance of the framework is improved. Finally, the order of addition of constraints is discussed to explain the universality of the proposed framework.
Chen, Chen, Qian, Lijun, Wu, Bing
Fusing Offline and Online Trajectory Optimization Techniques for Goal-to-Goal Navigation of a Scaled Autonomous Vehicle2021-01-00974/6/2021
Enabling self-driving vehicles to efficiently and autonomously navigate through an obstacle-filled environment remains a topic of significant contemporary research interest. Motion-planning frameworks, encapsulating both path- and trajectory-planning, have played a dominant role in realizing the deployment of a “sense-think-act” intelligence for autonomous vehicles. However, verification and validation of such intelligence on actual self-driving autonomous vehicles has been limited. Simulation-based verification and validation has the advantage of permitting diverse scenario-based testing and comprehensive “what-if” analyses - but is ultimately limited by the simulation fidelity and realism. In contrast, testing on full-scale real-world systems is constrained by the usual challenges of time, space, and cost engendered in reproducing diverse scenarios in practice. Further, motion-planning frameworks often engender a mixture of global-planning (typically performed offline) coupled with a sensor-based local-planning (typically done online), which requires both simulation and physical testing. Thus, scaled vehicle experimentation provides researchers with an exciting via-media to evaluate the performance and robustness of motion-planning algorithms on actual physical hardware - especially in real-time sensor-based motion planning settings. In this paper, we analyze a 1/10th scale F1/10 vehicle's performance in simulation and the actual hardware. A global planning algorithm is used to provide the waypoints for a feasible collision-free path between the start and goal configurations in the environment. We explored the deployment of Rapidly exploring Random Tree (RRT) and Rapidly exploring Random Tree* (RRT*). The Time Elastic Band local trajectory planner in ROS is then used for the realization of smooth, feasible paths between the waypoints. A comparison of validation in simulation has been provided with a detailed discussion of the parametric tuning for improving each case's performance.
Joglekar, Ajinkya, Deshpande, Bhooshan, Basuthakur, Mugdha, Krovi, Venkat N
Stability Criteria for Accurate Path Tracking in Automated Guided Vehicle Systems2021-01-00934/6/2021
Satisfactory performance of intelligent vehicles systems in tracking a predefined trajectory requires an efficient control scheme to generate steering control signals from posture errors (i.e., errors in position and orientation). For such systems, it is necessary at each instant to control steering action so that any deviation from the path is corrected in a stable manner, in a reasonable time and without any oscillation about the desired path. This paper deals with stability of motion and motion control of intelligent vehicle systems. In this regard, the general control structure and specification of an optimum range of predefined control parameters for accurate path tracking of these systems are determined. A two degree of freedom (DOF) nonlinear dynamic model is developed to represent their plane motion. Path tracking of the vehicle is attained by controlling the position and orientation errors about the trajectory, which is accomplished by modifying the steering input signal on the basis of error feedbacks to the controller. Employment of various stability criteria and other constraints such as applying the physical limits of the vehicle to the controlled system narrows down the range of control parameters, within which the controlled system would remain stable. Experimental results demonstrating the performance of the system are reported.
Mehrabi, Mostafa
Arrangement and Control Method of Cooperative Vehicle Platoon2021-01-01134/6/2021
With the development of cellular communication technology and for the sake of reducing drag resistance, the multi-lane platoon technology will be more prosperous in the future. In this article, the cooperative vehicle platoon method on the public road is represented. The method’s architecture is mainly composed of the following parts: decision-making, path planning and control command generation. The decision-making uses the finite state machine to make decision and judgment on the cooperative lane change of vehicles, and starts to execute the lane change step when the lane change requirements are met. In terms of path planning, with the goal of ensuring comfort, the continuity of the vehicle state and no collision between vehicles, a fifth-order polynomial is used to fit every vehicle trajectory. In terms of control command generation module, a model predictive control algorithm is used to solve the multi-vehicle centralized optimization control problem. We use the two DOF vehicle model to simulate vehicle dynamics. The front wheel angle and acceleration or braking commands of multiple vehicles are optimized to ensure that the vehicle can well follow the trajectory of the vehicle which is calculated by the control command generation module. At the same time, the energy consumed by performing steering, acceleration and deceleration is also minimized. Finally, in the simulation process, we simulate one direction two lanes scenario. The result shows that the proposed method can effectively handle multi-lane platoon re-configuration scenario.
Chen, Guosheng, Wu, Jian, Li, Shuai, Zhang, Jinghua, Du, Zhiqiang, Wang, Guojun, Chen, Zhicheng
Optimal Trajectory Generation for a Quadrotor Biplane TailsitterF-0076-2020-1632210/5/2020
This paper introduces a methodology for an optimization-based trajectory planner for the autonomous transition of a quadrotor biplane tailsitter (QRBP) between the flight modes of hover to forward flight and forward flight to hover. The trajectory planner uses a simplified first principles dynamic model of the QRBP in the formulation of a optimization problem for trajectory planning. Additional constraints on the trajectory are imposed based on physical limitations, such as available power, stall limits, among others. The cost function for the optimization problem is chosen to be the time-of-transition. The solution of this problem generates time-optimal state and input trajectories for transition. To validate the algorithm, the trajectories are tested on a flight dynamics simulation of a QRBP to demonstrate feasibility and tracking performance with an inner-loop PID feedback controller; and compared against trajectories generated from a heuristic approach. The results of the simulated tracking performance indicate the proposed trajectory planner is capable of generating feasible transition trajectories for the previously specified flight modes.
McIntosh, Kristoff, Reddinger, Jean-Paul, Mishra, Sandipan, Zhao, Di
Vision-based Autonomous Guidance Approach for a Nano Unmanned Aerial Vehicle Rotorcraft Towards Indoor Flight EnvironmentF-0076-2020-1632410/5/2020
Autonomous flight remains a major challenge for Nano Unmanned Air Vehicles (NUAVs). This research presented a light-weight vision-based navigation system which is suitable for NUAV rotorcrafts with restrictively limited payload capacity and computing resources. A visual-inertia compensation approach was proposed to obtain accurate indoor navigation and guidance for the homemade NUAV which weighting less than 50 g. The proposed visual guidance algorithm have been successfully recognized targets such as windows, gates, and narrow-corridor with 25 Hz guidance command output. Flight experiments shown that the NUAV rotorcraft can follow the path planning to achieve autonomous flight, and guide through gates and windows within GPS-denied indoor environment.
Wang, Guanlin, Li, Dehui, Xu, Panpan, Luo, Biuzhou, Wang, Xiuli, Xu, Beiju
Directional Vehicle Control by Steering the Third Axle to Provide Redundancy for Steer-by-Wire Systems and Highly Autonomous Vehicles02-13-03-00159/25/2020
A way of providing steering redundancy for highly autonomous vehicles or vehicles equipped with steer-by-wire systems by steering the rear axle for directional control of the vehicle has been previously proposed. In this study, we further investigate and improve on that concept and validate it through simulation and experimental testing on a vehicle. Consequently, we show that in the case of failure of primary front axle steering system, the vehicle controller steering command (in the case of autonomous driving) or the driver’s steering command (in the case of a steer-by-wire system) can be mathematically manipulated to generate a steering input at the rear axle, which results in the same yaw rate response as if the vehicle was steered from the front, and thus providing a way to control the vehicle should a failure occur in the primary steering system.
Nhila, Amine, Williams, Dan E.
An Efficient Path Planning Methodology Based on the Starting Region Selection2020-01-01184/14/2020
Automated parking is an efficient way to solve parking difficulties and path planning is of great concern for parking maneuvers [1]. Meanwhile, the starting region of path planning greatly affects the parking process and efficiency. The present research of the starting region are mostly determined based on a single algorithm, which limits the flexibility and efficiency of planning feasible paths. This paper, taking parallel parking and vertical parking for example, proposes a method to calculate the starting region and select the most suitable path planning algorithm for parking, which can improve the parking efficiency and reduce the complexity. The collision situations of each path planning algorithm are analyzed under collision-free conditions based on parallel and vertical parking. The starting region for each algorithm can then be calculated under collision-free conditions. After that, applicable starting regions for parking can be obtained, and each of those regions corresponds to a parking path planning algorithm. However, there always exists overlapped starting regions, which can be applied to multiple parking path planning algorithms. In order to select the most suitable algorithm to plan the parking path, the priority order of algorithms is decided based on the preference criterion function. The collision-free parking path can be generated following the priority order. Based on the modified B-spline curves, a continuous-curvature path is presented. The simulation results based on MATLAB/Simulink and PreScan show that the methodology can smoothly judge the feasibility of automated parking in vehicle’s current position and plan the most suitable parking path. The proposed methodology can calculate the starting region of automated parking rapidly and plan more efficient parking path compared with other methods.
Chen, Xin, Qin, Zhaobo, Fan, Jingjing, Zhou, Huajian, Chen, Liang
Optimal Cooperative Path Planning Considering Driving Intention for Shared Control2020-01-01114/14/2020
This paper presents an optimal cooperative path planning method considering driver’s driving intention for shared control to address target path conflicts during the driver-automation interaction by using the convex optimization technique based on the natural cubic spline. The optimal path criteria (e.g. the optimal curvature, the optimal heading angle) are formulated as quadratic forms using the natural cubic spline, and the initial cooperative path profiles of the cooperative path in the Frenet-based coordinate system are induced by considering the driver’s lane-changing intention recognized by the Support Vector Machine (SVM) method. Then, the optimal cooperative path could be obtained by the convex optimization techniques. The noncooperative game theory is adopted to model the driver-automation interaction in this shared control framework, where the Nash equilibrium solution is derived by the model predictive control (MPC) approach. Finally, the proposed framework is tested with different driver’s driving intentions to avoid obstacles on a straight road and a curvy road. As a result, the planned path could continuously adapt to the driving intention and various road shapes, and the path conflicts between the human driver and the controller is also decreased by the proposed cooperative path planning method in the game-based shared control framework.
Li, Mingjun, Song, Xiao-lin, Cao, Dongpu, Cao, Haotian
Intention-aware Lane Changing Assistance Strategy Basing on Traffic Situation Assessment2020-01-01274/14/2020
Traffic accidents avoidance is one of the main advantages for automated vehicles. As one of the main causes of vehicle collision accidents, lane changing of the ego vehicle in case that the obstacle vehicles appear in the blind spot with uncertain motion intentions is one of the main goals for the automated vehicle. An intention-aware lane changing collision assistance strategy basing on traffic situation assessment in the complex traffic scenarios is proposed in this paper. Typical Regions of Interest (ROI) within the detection range of the blind spots are selected basing on the road topology structures and state space consisting of the ego vehicle and the obstacle vehicles. Then the motion intentions of the obstacle vehicles in ROI are identified basing on Gaussian Mixture Models (GMM) and the corresponding motion trajectories are predicted basing on the state equation. Traffic situation is assessed according to the index of the motion intentions and the coupling tendency between the ego vehicle and the obstacle vehicles and the risk level is graded basing on the map with collision time. Lane keeping assist is carried out according to the assessment result of the traffic situation. Testing scenarios with the straight road and T-junction are designed and a co-simulation environment consisting of CarMaker and Mathwork Simulink is established to verify the proposed strategy in complex traffic scenes. Simulation results present an adaptive ROI and a high identification accuracy for motion intentions of the obstacle vehicles. What’s more, it shows that the traffic situation can be accurately evaluated and the ego vehicle can be effectively controlled with the appearance of the high-risk vehicles.
Wu, Jian, Liu, Sihan, He, Rui, Sun, Bohua
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
Decision Making and Trajectory Planning for Lane Change Control Inspired by Parallel Parking2020-01-01344/14/2020
Lane-changing systems have been developed and applied to improve environmental adaptability of advanced driver assistant system (ADAS) and driver comfort. Lane-changing control consists of three steps: decision making, trajectory planning and trajectory tracking. Current methods are not perfect due to weaknesses such as high computation cost, low robustness to uncertainties, etc. In this paper, a novel lane changing control method is proposed, where lane-changing behavior is analogized to parallel parking behavior. In the perspective of host vehicle with lane-changing intention, the space between vehicles in the target adjacent lane can be regarded as dynamic parking space. A decision making and path planning algorithm of parallel parking is adapted to deal with lane change condition. The adopted algorithm based on rules checks lane-changing feasibility and generates desired path in the moving reference system at the same speed of vehicles in target lane. Compared to algorithm for static parking space, the uncertainty of the space between moving vehicles and host vehicle dynamics raises stricter requirements for algorithms. Works are conducted to deal with dynamically changing scenarios, such as design of safety zone and exit conditions to avoid collision. Simulation under PreScan-Simulink environment shows that the proposed method outperforms in lane change scenarios and achieves strong robustness to inter-vehicle dynamics.
Yu, Liangyao, Ru, Ze, Lu, Zhenghong, Liang, Guanqun, Xiong, Cenbo, Lanie, Abi, Wang, Ruyue
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
Development of the Rig and Hardware-in-the-Loop Test Bench for Evaluating Steering Performance2020-01-06474/14/2020
The development of vehicles faces changes in many future flows. The vehicle’s power transfer systems are being changed from conventional types to Hybrid, Electric and Hydrogen vehicles. At this moment, the technology of EPS (Electric Power Steering) system has been expanding from a simple torque assist system to LKAS(Lane Keeping Assist System), PAP(Park Assist Pilot), ALCAS(Active Lane Change System), ADAS(Advanced Driver Assistance System). A good test bench is necessary for the evaluation of both hardware and control logics of EPS in these complexities of development process. Simultaneous Rig and HILS tests can be performed to check that the steering hardware system can perform to the concept of the development vehicle and develop EPS control logic performances. The hardware performance of the steering system might be evaluated based on measured friction and stiffness, taking into account various driving conditions. And the control logic of the EPS can be evaluated based on the response capability and steering torque measured through the appropriate vehicle model which could represent virtual driving conditions.
Kim, Changsu, Lee, Byungrim, Park, Youngdae
A Dynamic Trajectory Planning for Automatic Vehicles Based on Improved Discrete Optimization Method2020-01-01204/14/2020
The dynamic trajectory planning problem for automatic vehicles in complex traffic scenarios is investigated in this paper. A hierarchical motion planning framework is developed to complete the complex planning task. An improved dangerous potential field in the curvilinear coordinate system is constructed to describe the collision risk of automatic vehicles accurately instead of the discrete Gaussian convolution algorithm. At the same time, the driving comfort is also considered in order to generate an optimal, smooth, collision-free and feasible path in dynamics. The optimal path can be mapped into the Cartesian coordinate system simply and conveniently. Furthermore, a velocity profile considering practical vehicle dynamics is also presented to improve the safety and the comfort in driving. The effectiveness of the proposed dynamic trajectory planning is verified by numerical simulation for several typical traffic scenarios.
Zeng, Pengyun, Ling, Zheng
GNSS-Based Lane Keeping Assist System Using Model Predictive Control and Time Delay Compensation2020-01-10234/14/2020
In recent decades, research and development in the field of autonomous vehicles have rapidly increased throughout the world, and autonomous driving technologies have begun to be applied to mass production vehicles. Especially recently, even affordable mass production vehicles have begun to be equipped with some autonomous driving systems such as a Lane Keeping Assist (LKA) system. In general, mass-produced LKA systems use a lane detection camera as a means of keeping the lane. One of the common limitations of camera-based LKA systems is that the lane keeping performance significantly decreases when the camera cannot detect lane markings for various reasons such as snow coverage or blurred lane markings. To overcome this limitation, we have developed Global Navigation Satellite System (GNSS)-based LKA systems, which are not affected by the surrounding environment such as weather and the condition of lane markings. In our latest study, we applied Model Predictive Control (MPC) to our GNSS-based LKA system so as to enhance lane-keeping performance. We then revealed that the GNSS-based LKA system with MPC had low robustness regarding the time delay of a GNSS and that countermeasures for the time delay were necessary. In this paper, we apply Smith predictor-like Time Delay Compensation (TDC) to compensate for the time delay. The TDC predicts the current state variables from the past sensor signals based on the vehicle dynamics. We demonstrate that the TDC stabilizes the LKA system even when the GNSS has a time delay in a simulation. Furthermore we add another TDC to compensate for the time delay of Electrical Power Steering (EPS) with the aim of reducing the oscillation of the steering wheel angle. Finally, we evaluate the lane keeping performance in a real-vehicle experiment on a snow-covered highway.
Tominaga, Kenta, Takeuchi, Yu, Kitano, Hiroaki, Tomoki, Uno, Quirynen, Rien, Cairano, Stefano
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.
A Communication-Free Human-Robot-Collaboration Approach for Aircraft Riveting Process Using AI Probabilistic Planning2020-01-00133/10/2020
In large scale industries attempts are continuously being made to automate assembly processes to not only increase productivity but also alleviate non-ergonomic tasks. However this is not always technologically possible due to specific joining challenges and the high number of special-purpose parts. For the riveting process, for example, semi-automated approaches represent an alternative to optimizing aircraft assembly and to reduce the exposure of workers to non-ergonomic conditions entailed by performing repetitive tasks. In [1], a semi-automated solution is proposed for the riveting process of assembling the section barrel of the aft section to its pressure bulkhead. The method introduced a dynamic task sharing strategy between human and robot that implements interaction possibilities to establish a communication between a human and a robot in Human-Robot-collaboration fashion. Although intuitive, interacting with the robot constantly is still not natural for the worker as in the manual process no explicit communication between both workers is needed. In this work a communication-free Human-Robot-collaboration solution is presented. The method developed not only enables sharing assembly missions by dividing tasks based on skills, but also offers the possibility of decision making to the robot. In this context, off-the-shelf Artificial Intelligence planning tools are used to model the work-flow of the human as well as the task of the robot handling alongside possible uncertainties yielding while perceiving the environment or the activity of the human.
Rekik, Khansa, Müller, Rainer, Hoffmann, Jörg, Vette, Matthias
Ford's max Mustang brings ‘world class’ into the sports coupe conversation20AUTP03_123/1/2020
There's the old saw about a something being better than the sum of its parts. That phrase applies to the 2020 Ford Mustang Shelby GT500 - despite most of its parts being categorically bombastic. Its performance far exceeds any old-school ponycar yardstick, but those expecting a straight-line brute will be surprised. The Shelby GT500's sublime chassis stands it more in the company of powered-up Porsches than howling Hellcats. The supercharged “Predator” 5.2-L V8's stun-grenade numbers - SAE-rated 760 hp and 625 lb-ft (847 Nm) - might logically be blamed for perpetuating any perceptions of the Shelby GT500 as one-trick musclecar. It's the “most power-dense V8 in America,” boasts Mustang chief engineer Carl Widman. The backstory is nearly as good as the raw performance: it was long assumed that the Predator would be a supercharged variant of the heralded and high-revving 5.2-L “Voodoo” flat-plane-crankshaft V8 that debuted in 2015's Mustang Shelby GT350. Instead, engineers fitted a conventional cross-plane crank and changed nearly every internal component, retaining only the basic architecture from the Voodoo.
Visnic, Bill
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
New Solution to Elderly Falls: Drones, Smartphones and SensorsTBMG-361543/1/2020
A new system has been designed by a team of researchers from Iraq and the University of South Australia to remotely monitor elderly people, detecting abnormalities in their heart rate and temperature that can lead to falls, and provide urgent first aid via a drone if a fall occurs.
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
Crank-Lever Electromagnetic Damper (CLEMD) Design for Automobile Suspension System06-13-01-00022/4/2020
An effective damper is among the most important components of the suspension system. It ensures the right amount of damping force is acting on the suspension system to provide comfort to the passengers and proper road holding to tires. Unfortunately, the energy absorbed by the dampers from the suspension system gets wasted in the form of heat. In this article, it is proposed to use innovative electromagnetic damper (EMD) with a crank-lever mechanism to recover energy from the suspension system. The goal is to develop a lightweight design of EMD that can recover a high amount of power. For the design, an off-road vehicle is used since in off-road vehicles the amount of power wasted in the suspension system is high. Three different design approaches are used, which include single-stage gearbox type, two-stage gearbox type, and three-stage gearbox type of CLEMD. Out of them, the best design, i.e. three-stage gearbox type of CLEMD is selected because of minimum weight and inertia of the components. This article is focused on the design and analysis of the three-stage gearbox type of CLEMD. On the basis of the output of numerical simulations of vehicle model, specifications for crank-lever electromagnetic damper (CLEMD) are driven and design is carried out. Also, performance analyses of CLEMD are carried out by interfacing model of CLEMD with the model of a vehicle. The advantage of CLEMD is it can act as an actuator to provide active force in an active suspension system.
Todmal, Prashant Eknath, Melzi, Stefano
Mercedes Vision AVTR concept a beacon for sustainability20AUTP02_111/1/2020
At the keynote for the 2020 Consumer Electronics Show (CES) in Las Vegas, Mercedes-Benz unveiled its VISION AVTR concept vehicle representing a far-forward look at the company's future design, materials and technologies. Inspired by the James Cameron film Avatar (with the director on hand at CES for its reveal), and representing a sustainable vision of zero-emission mobility, the VISION AVTR concept was introduced by Ola Källenius, M-B's chairman of the board. The fully-electric, AWD, 4-seat concept features a 110-kWh battery and a 700-km (434-mi) range. It is M-B's idea of sustainable luxury - a form of electro-mobility “in harmony with people and nature.” The VISION AVTR concept uses 100%-recyclable organic battery technology and leverages a host of artificial intelligence (AI) to maximize vehicle performance and efficiency, including integrated solar-panels designed to provide power back to the grid.
Seredynski, Paul
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.
Localization Requirements for Autonomous Vehicles12-02-03-00129/24/2019
Autonomous vehicles require precise knowledge of their position and orientation in all weather and traffic conditions for path planning, perception, control, and general safe operation. Here we derive these requirements for autonomous vehicles based on first principles. We begin with the safety integrity level, defining the allowable probability of failure per hour of operation based on desired improvements on road safety today. This draws comparisons with the localization integrity levels required in aviation and rail where similar numbers are derived at 10−8 probability of failure per hour of operation. We then define the geometry of the problem where the aim is to maintain knowledge that the vehicle is within its lane and to determine what road level it is on. Longitudinal, lateral, and vertical localization error bounds (alert limits) and 95% accuracy requirements are derived based on the United States (US) road geometry standards (lane width, curvature, and vertical clearance) and allowable vehicle dimensions. For passenger vehicles operating on freeway roads, the result is a required lateral error bound of 0.57 m (0.20 m, 95%), a longitudinal bound of 1.40 m (0.48 m, 95%), a vertical bound of 1.30 m (0.43 m, 95%), and an attitude bound in each direction of 1.50° (0.51°, 95%). On local streets, the road geometry makes requirements more stringent where lateral and longitudinal error bounds of 0.29 m (0.10 m, 95%) are needed with an orientation requirement of 0.50° (0.17°, 95%).
Reid, Tyler G.R., Houts, Sarah E., Cammarata, Robert, Mills, Graham, Agarwal, Siddharth, Vora, Ankit, Pandey, Gaurav
Improving Lidar - or Defeating It19AVEP09_089/1/2019
The buzz at Sensors Expo pitted lidar-tech optimism against the reality of an impending shakeout. For more than a decade, the lidar market has been led by Velodyne and its spinning towers of 64 or 128 laser beams. But the relatively high cost, delicate architecture, and beefy form factor have made it a competitive target. The growing ranks of competitors fall roughly into two camps. There are the fledgling lidar-makers with novel approaches to distance measurement, laser wavelength, and beam steering. And there are those with radar and vision systems promising lidar-level sensing capabilities at a lower cost. The jockeying for position was on full display at the 2019 Sensors Expo and Conference, held in San Jose, Calif. “The greatest amount of discussion is about lidar right now because there are a lot of startups in that space,” observed Jim Hines, an independent consultant working on semiconductor and sensor technologies for connected and autonomous vehicles.
Berman, Bradley
Software Enables Robots to Self-Right After OverturningTBMG-351379/1/2019
The Advanced Explosive Ordnance Disposal Robotic System (AEODRS) features a modular open systems architecture that enables the robot to be self-righting after a fall. The self-righting ability is extended to robots with a greater number of degrees of freedom (joints).
EDITORIAL: AI, ADAS & AVs-oh my!19TOFHP08_068/1/2019
Active safety and advanced driver-assistance systems (ADAS), along with increasingly sophisticated artificial intelligence (AI) platforms-are the building blocks essential to climbing the SAE levels of automation. Acquisitions, partnerships and advanced-technology demonstrations in these areas are occurring at a dizzying rate, as the industry has set its sights on Level 4 (L4) automated vehicles (AVs). One major in-process merger involves two heavyweights in this space, ZF and WABCO. In June, WABCO shareholders approved the acquisition by ZF, which both companies expect to finalize in early 2020. Importantly, the acquisition will expand ZF's expertise to include commercial vehicle (CV) braking solutions for the first time-a significant capability for the control of automated driving functions like emergency braking maneuvers of trucks and trailers. This fully integrated system approach is expected to accelerate the introduction of autonomous CV functions moving forward.
Gehm, Ryan
Steering for Off-Road, Rubber-Tired MachinesJ1511_201907 (Current)7/29/2019
This SAE Standard applies to off-road rubber-tired machines having rated speed capability exceeding 20 km/h. Only the following machine categories in SAE J1116 are included in the scope of this document. a. Earthmoving b. Other than earthmoving: except rollers and compactors c. General purpose industrial d. Forestry e. Specialized mining machinery Applicable steering systems include the following means of providing power for steering: a. Manual steering b. Power-assisted steering c. Full-power steering This document does not imply that secondary steering is mandatory. However, if secondary steering is provided, performance and test requirements are included.
OPTC1, Personnel Protection (General)
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