Browse Topic: Human factors
As part of a human factors research project aimed at optimizing technical documentation used in helicopter maintenance with multimedia elements, we compared different instruction formats to observe their effects on the performance of an assembly task. This task offers us the opportunity to test procedures that call for similar actions as a maintenance task (e.g., localization, action sequencing, assembly). Static (i.e., image and image with text) and dynamic instruction formats (i.e., video, video with text and video with audio) were compared to determine if dynamic formats allowed a better motor performance of the task for assembly reaction time (time needed to complete the assembly) and accuracy. We were also interested in how the use of the text instructions interacted with both visual dynamic and static instructions. Reaction times were recorded and measured with eye tracking data. Subjective data was collected in questionnaires during and after the experiment. Results showed
ABSTRACT Shipboard operations present a unique set of challenges to the pilot-vehicle system. This work addresses problems specific to piloted rotorcraft in the simulated shipboard environment, namely cueing and ship motion, and represents the completion of a three-year effort focused on fixed-base, pilot-in-the-loop rotorcraft flight simulations. Instructors from the United States Naval Test Pilot School, with extensive operational and test experience, participated in the study. Two cueing sets, one for the approach task and another for the hover task, were developed in order to provide intuitive guidance of cyclic and collective inputs. Data were gathered for each task with the cueing system both on and off. The evaluation criteria used to determine the usefulness of the provided cueing were based on pilot workload assessment, profile performance and inceptor activity. The approach task cueing provides the pilot with a preset approach profile defined by altitude and airspeed cueing
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
This paper examines the Handling Quality Rating (HQR) of the Model-Based Pilot Controller (MBPC) in failure scenarios within the Automatic Flight Control System (AFCS). The MBPC aims to automate the testing of malfunctions in the AFCS of the T625 Gökbey platform. It is constructed using optimal control and estimation theory, with the cost function representing human characteristics determined by weighting matrices. The optimal values of weighting matrices that minimize the cost function are achieved via Genetic Algorithm. This algorithm utilized to systematically minimize user-defined cost functions tailored to optimize performance for selected maneuvers within the scope of ADS33E-PRF, considering user-defined constraints. Time-domain metric performance is provided for two maneuvers: vertical maneuver and hovering turn. The HQRs of the MBPC evaluated according to Power Frequency and Inceptor Peak Power-Phase (IPPP) metrics. The MBPC satisfies the ADS33 desired performance criteria in
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ABSTRACT
The devices of this SAE Standard provide the means by which passenger compartment dimensions can be obtained using a deflected seat rather than a free seat contour as a reference for defining seating space. All definitions and dimensions used in conjunction with this document are described in SAE J1100. These devices are intended only to apply to the driver side or center occupant seating spaces and are not to be construed as instruments which measure or indicate occupant capabilities or comfort. This document covers only one H-point machine installed on a seat during each test. Certified H-point templates and machines can be purchased from: SAE International 400 Commonwealth Drive Warrendale, PA 15096-0001 Specific procedures are included in Appendix A for seat measurements in short- and long-coupled vehicles and in Appendix B for measurement of the driver seat cushion angle. Specifications and a calibration inspection procedure for the H-point machine are given in Appendix C
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The National Research Council of Canada and Université de Sherbrooke performed flight testing of an Actively Stabilized Slung Load on the NRC Bell 206 Research Aircraft. Hover, Attitude Capture, NRC designed Lateral Precision Hover, and Frequency Sweep mission tasks were performed for bare airframe and slung load aircraft configurations. The load mass ratio was 0.12 while the slung load pendulum mode was 1.3 rad/sec at a damping ratio of 0.2 for the 40-pound per active tether saturation load system setting. Time domain response indicated that the load remained controllable with damped and underdamped behaviors. Frequency domain analyses confirmed pilot comments indicating HQR 4 handling qualities ratings for bare airframe and stable slung load behavior. This rating degraded to HQR 5 for task execution with slung load oscillation. Pilot workload was due to lateral cycle input requirements of 2 to 3 inch amplitudes at 1 to 2 Hz frequency. Operationally, the coincidence of pilot inputs
A core mission of the CH-53K involves flying in severe brownout conditions, which increases pilot workload and can reduce mission success rates. With state of the art Fly by Wire capability, the CH-53K leverages the computational power of a flight control computer to provide higher order control modes which reduce pilot workload in all degraded visual environments such as brownout. The preliminary design of the flight control system included the inceptor system and low speed control architecture, which created an expansive design space. High fidelity simulations, cockpit mockup, and use of the NRC Bell 412 in-flight simulation Advanced Systems Research Aircraft surrogate aircraft allowed for a comprehensive development environment to narrow down to final control system design. The final design of the low speed maneuvering provided a command strategy similar to translational rate commend yet provided an approach profile that more closely replicated a piloted approach to a landing zone
This paper describes the development of full flight envelope dynamic inversion outer-loop control laws used to control airspeed and flight path for two Future Vertical Lift-relevant rotorcraft configurations - a lift offset coaxial helicopter with a pusher propeller and a tiltrotor. The outer-loop control laws for both aircraft include a control allocation scheme to account for redundant controls and reduce pilot workload. A piloted simulation experiment was conducted at the Penn State Flight Simulator facility using a series of high-speed handling qualities demonstration maneuvers to evaluate the handling qualities of the control laws. Overall, the outer-loop control laws for both coaxial-pusher and tiltrotor aircraft were assigned Level 1 handling qualities for the Break Turn and High-Speed Acceleration/Deceleration tasks, and reduced pilot workload over previously developed inner-loop control laws. The outer-loop control laws also improved performance and reduced pilot workload in a
Helicopter shipboard launch and recovery are some of the most challenging operations to date, owing to the pilot workload associated with the tasks. A variety of environmental conditions such as random deck motion, heavy sea states and unsteady aerodynamic interactions can be attributed to the same. This paper highlights the development and assessment of a visual flight lead cue for real-time guidance and pilot workload reduction. For a chosen approach-turnland maneuver, the pilot workload is assessed using data from pilot-in-the-loop (PIL) flight simulations. Quantitative metrics based on Time-Frequency Representation (TFR) are used to evaluate pilot workload and the analysis of workload in the presence and absence of the cue is presented. Furthermore, the deviations from the desired path are studied using root-mean-square error (RMSE) for the cue on/off cases. The relation between pilot workload and path following is analyzed to determine the efficacy of the cue provided.
The benefits of developing objective measures of handling qualities, more specifically pilot workload, are of great interest to the United States Navy. Several lines of research have been initiated to that end with this study focusing on inceptor activity. Potential pilot inceptor workload metrics were applied to a data set consisting of ten pilots conducting simulated approach and hover tasks to a DDG-class ship. Piloted handling qualities ratings were recorded for the tasks. Workload variation was induced by using different aircraft response types, varying degrees of ship motion, and the presence/absence of cueing. Using only pilot inceptor state data, potential workload metrics were evaluated and correlations with handling qualities ratings were examined. Methods to apply traditionally single-axis metrics to multi-axis tasks were explored, inconclusively. Predictive ability of the simple metrics improved by breaking tasks into pseudo-time invariant sub-tasks. A multi-axis metric
This paper presents preliminary results of a pilot-in-the-loop (PIL) study of different cueing designs to reduce pilot workload in rotorcraft shipboard landings. The participants were tasked with flying an approach to touchdown on the deck of an Arleigh Burke Flight IIA class Destroyer under both day visual flight rules (VFR) and night-unaided, zeroillumination conditions. For each condition, the participants were presented with three different cue types. For the day iterations these were a generic military standard heads up display (HUD), a ship fixed tunnel in the sky (tunnel), and a virtual flight lead cueing system (FLCS). The zero-illumination night condition was deemed impossible to land with only the HUD, so it was replaced with a combination of the tunnel and FLCS for the purpose of gaining initial feedback on combining elements of different systems. Terminal landing constraints (location, heading, and impact velocity) were used as measures of pilot performance, the NASA Task
This work examines the handling qualities (HQ) rating scale from a psychophysical perspective, characterizing workload as the response to a stimulus composed of input to the pilot and pilot outputs. Previous work by the author examining three different display tracking tasks indicated that pilot workload is effectively a logarithmic function of tracking error rate and control rate. This approach, called the Spare Capacity OPerations Estimator (SCOPE), is extended to flight and Handling Qualities data collected (109 runs) for the slalom Mission Task Element (MTE) using the U.S. Army’s JUH-60A RASCAL aircraft. Attitude and Rate Command response types as well as various forcefeel configurations were tested. Based on flight data observation a novel and intuitive action model is proposed for the slalom MTE whereby the pilot operates on the relative angle between the ground track and the upcoming cone’s location (effectively the cone’s location on the windscreen relative to the aircraft nose
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