13,535 research outputs found

    Proportional-integral-derivative control algorithm with delay compensation for steer-by-wire under network controlled system

    Get PDF
    Controller Area Network (CAN) is a popular network commonly used in the automotive industry which is an advanced serial bus system designed for real-time control system. This thesis addresses the modelling and controller design for Steer-by-Wire (SbW) system under the influence of a network controlled system. The analysis of the control performance of the SbW system under several CAN configuration setting is discussed in detail. The mathematical model of the SbW system is adopted from previous research works using both steering rack dynamic and the vehicle system dynamic. Proportional-Integral-Derivative (PID) controller that can compensate delay is designed to achieve the desired control performance of the SbW system. The analysis of the control performance is solely based on the simulation conducted in the Matlab/Simulink software environment with Truetime toolbox to simulate the real time performance of the SbW system. The simulation is performed based on nine different cases in the event of several difference in the CAN network properties such as the network speed, sampling periods, scheduling techniques, rate of data losses, interruption by higher priority data and clock drift to evaluate the control performance of the SbW system. The result is found that the SbW system control performance deteriorates by the selection of low network speed, sensor’s sampling periods and the rate of data losses

    The psychology of driving automation: A discussion with Professor Don Norman

    Get PDF
    Introducing automation into automobiles had inevitable consequences for the driver and driving. Systems that automate longitudinal and lateral vehicle control may reduce the workload of the driver. This raises questions of what the driver is able to do with this 'spare' attentional capacity. Research in our laboratory suggests that there is unlikely to be any spare capacity because the attentional resources are not 'fixed'. Rather, the resources are inextricably linked to task demand. This paper presents some of the arguments for considering the psychological aspects of the driver when designing automation into automobiles. The arguments are presented in a conversation format, based on discussions with Professor Don Norman. Extracts from relevant papers to support the arguments are presented

    UTHM water quality classification based on sub index

    Get PDF
    River or stream at their source is unpolluted, but as water flow downstream, the river or lake is receiving point and non-point pollutant source. Ammoniacal nitrogen (NH3- N) and suspended solids (SS) strongly influences the dynamics of the dissolved oxygen in the water. Studies on monitoring this parameter were conducted for a river or lake but limited to the small man-made lake. This study is initiate to determine the changes in water quality of UTHM watershed as the water flows from upstream to downstream. The monitoring of NH3-N and TSS were monitored at two sampling schemes, 1) at the two-week interval and, 2) at a daily basis followed by the determination of the water quality sub-index particularly SIAN and SISS. The results showed that the two lakes in UTHM watershed were classified as polluted. In conclusion, the remedial action should be implemented to improve the water quality to meet the requirements at least to meet the recreational purpose

    From fly-by-wire to drive-by-wire: Safety implications of automation in vehicles

    Get PDF
    The purpose of this paper is to critically review the current trend in automobile engineering toward automation of many of the functions previously performed by the driver. Working on the assumption that automation in aviation represents the basic model for driver automation, the costs and benefits of automation in aviation are explored as a means of establishing where automation of drivers' tasks are likely to yield benefits. It is concluded that there are areas where automation can provide benefits to the driver, but there are other areas where this is unlikely to be the case. Automation per se does not guarantee success, and therefore it becomes vital to involve Human Factors into design to identify where automation of driver functions can be allocated with a beneficial outcome for driving performance

    Roving vehicle motion control Final report

    Get PDF
    Roving vehicle motion control for unmanned planetary and lunar exploratio

    Summary of NASA landing-gear research

    Get PDF
    Research relative to tire tread, powered-wheel taxiing, air cushion landing systems, and crosswind landing gear is discussed

    Model Predictive torque vectoring control for electric vehicles near the limits of handling

    Get PDF
    In this paper we propose a constrained optimal control architecture to stabilize a vehicle near the limit of lateral acceleration using the rear axle electric torque vectoring configuration of an electric vehicle. A nonlinear vehicle and tyre model is employed to find reference steady-state cornering conditions as well as to design a linear Model Predictive Control (MPC) strategy using the rear wheels' slip ratios as input. A Sliding Mode Slip Controller then calculates the necessary motor torques according to the requested wheel slip ratios. After analysing the relative trade-offs between performance and computational effort for the MPC strategy, we validate the controller and compare it against a simpler unconstrained optimal control strategy in a high fidelity simulation environment

    Trajectory generation for road vehicle obstacle avoidance using convex optimization

    Get PDF
    This paper presents a method for trajectory generation using convex optimization to find a feasible, obstacle-free path for a road vehicle. Consideration of vehicle rotation is shown to be necessary if the trajectory is to avoid obstacles specified in a fixed Earth axis system. The paper establishes that, despite the presence of significant non-linearities, it is possible to articulate the obstacle avoidance problem in a tractable convex form using multiple optimization passes. Finally, it is shown by simulation that an optimal trajectory that accounts for the vehicle’s changing velocity throughout the manoeuvre is superior to a previous analytical method that assumes constant speed
    corecore