Study on the potential application of electronic wedge brake for vehicle brake system

This paper presents a study of the potential application of an electronic wedge brake for vehicle brake system using human-in-the-loop simulation. Simulation was made in MATLAB Simulink software which interfaces an imaginary vehicle with a real time input from a human, such as throttle and brake input. The imaginary vehicle model that is used is a vehicle dynamic model that has been validated experimentally using an instrumented experimental vehicle. A validated electronic wedge brake actuator model was then used as the brake actuator model where a suitable control strategy, namely proportional-integral-derivative and proportional-integral controllers, was utilised as the force and gapping control respectively. To verify the effectiveness of the proposed actuator in a vehicle, the simulation results are compared with the results of human-in-the-loop simulation of a vehicle using a conventional hydraulic brake and the response of the experimental vehicle using the same dynamic test, namely the sudden braking test. The simulation results show that the proposed simulation method and actuator with appropriate controller strategy have similar behaviour to a hydraulic brake in terms of its capability to produce the desired braking force to reduce the speed and halt the vehicle. The outcomes from this study can be considered in design optimisation and implementation in a real vehicle

Integrated braking control for electric vehicles with in-wheel propulsion and fully decoupled brake-by-wire system

This paper introduces a case study on the potential of new mechatronic chassis systems for battery electric vehicles, in this case a brake-by-wire (BBW) system and in-wheel propulsion on the rear axle combined with an integrated chassis control providing common safety features like anti-lock braking system (ABS), and enhanced functionalities, like torque blending. The presented controller was intended to also show the potential of continuous control strategies with regard to active safety, vehicle stability and driving comfort. Therefore, an integral sliding mode (ISM) and proportional integral (PI) control were used for wheel slip control (WSC) and benchmarked against each other and against classical used rule-based approach. The controller was realized in MatLab/Simulink and tested under real-time conditions in IPG CarMaker simulation environment for experimentally validated models of the target vehicle and its systems. The controller also contains robust observers for estimation of non-measurable vehicle states and parameters e.g., vehicle mass or road grade, which can have a significant influence on control performance and vehicle safety

POSITION TRACKING CONTROL OF DC MOTOR FOR FRONT WHEEL SYSTEMS VIA HILS SIMULATION METHOD

This paper present about position tracking control of DC motor to be used as the actuator controller for the front wheel test rig system. The controller strategy that was developed is based on Proportional-Integral-Derivative (PID) controller. It consists of one single closed control loops namely position tracking control loop.  To evaluate the effectiveness of the proposed controller, simulation and experimental studies were performed by using various input demand such as saw tooth, sine and step functions in 5°, 10°, 15° and 20° with the present of steering ratio at 360:20. The results, it is found that the trend between simulation and experimental data are similar with the command position with acceptable level of error which less than 10% for application at hand

Advanced Control and Estimation Concepts, and New Hardware Topologies for Future Mobility

According to the National Research Council, the use of embedded systems throughout society could well overtake previous milestones in the information revolution. Mechatronics is the synergistic combination of electronic, mechanical engineering, controls, software and systems engineering in the design of processes and products. Mechatronic systems put “intelligence” into physical systems. Embedded sensors/actuators/processors are integral parts of mechatronic systems. The implementation of mechatronic systems is consistently on the rise. However, manufacturers are working hard to reduce the implementation cost of these systems while trying avoid compromising product quality. One way of addressing these conflicting objectives is through new automatic control methods, virtual sensing/estimation, and new innovative hardware topologies

Full-scale testing of a novel slip control braking system for heavy vehicles

This paper summarises the measured emergency braking performance of a tri-axle heavy goods vehicle semitrailer fitted with a novel pneumatic slip control braking system developed by the Cambridge Vehicle Dynamics Consortium. Straight-line braking tests were carried out from 40 km/h in order to compare a commercially electro-pneumatic available anti-lock braking system and the Cambridge Vehicle Dynamics Consortium system, which has bi-stable valves coupled with a sliding-mode slip controller. On average, the Cambridge Vehicle Dynamics Consortium system reduced the stopping distance and the air use by 15% and 22% respectively compared with those for the conventional anti-lock braking system. The most significant improvements were seen on a wet basalt-tile surface (with similar friction properties to ice) where the stopping distance and the air use were improved by 17% and 30% respectively. A third performance metric, namely the mean absolute slip error, is introduced to quantify the ability of each braking system to track a wheel slip demand. Using this metric, the bi-stable valve system is shown to improve the wheel slip demand tracking by 62% compared with that of the conventional anti-lock braking system. This improvement potentially allows more accurate control of the wheel forces during extreme manoeuvres, providing scope for the future development of advanced stability control systems. This work was supported by Haldex Brake Products Ltd, the New Zealand Tertiary Education Commission and the Cambridge Vehicle Dynamics Consortium (CVDC).This is the author accepted manuscript. The final version is available from Sage via http://dx.doi.org/10.1177/095440701560480

A Dynamic Model Of Electronic Wedge Brake: Experimental, Control And Optimization

This paper discusses the process of modelling and parameter selection for the creation of the electronic wedge brake system (EWB). The system involves a permanent magnet DC engine (PMDC) that drives the motor, the gear leadscrew, and the brake core. The proposed model is simpler and more flexible which can be used in both the most well-known EWB designs either natural or optimized EWB. The selection of the motor is rendered according to the brake specifications. The wedge angle profile is centred on the derivation of EWB system that consists of brake actuator, wedge mechanism dynamic, and wedge characteristic brake factor. Control and optimization are carried out with specific coefficients of friction of the brake pads to maintain operating reliability. A 5th-order brake simulation model of the EWB in a single state-space was derived and a simulation was conducted to verify the distribution of force. The efficiency of the brake clamping force control system was assessed by proportional-integral-derivative (PID) control. The performance of the proposed controller is verified in simulations and experiments using a prototype electronic wedge brake. The research findings indicate, the actuator restriction is deemed to achieve consistent performance against full range braking during the EWB control desig

Modeling and validation of electronic wedge brake mechanism for vehicle safety system

This paper presents the performance characteristic of an electronic wedge brake (EWB) mechanism for a vehicle braking system. Based on a Gaussian cumulative distribution method, a non-parametric model, using Bell-Shaped curve method has been proposed in this study to characterize the behavior of an actual EWB mechanism. Therefore, a brake test rig has been developed to investigate the performance of the Bell-Shaped curve model. For the purpose of validation of EWB, an electronic control unit (ECU) which consists of microcontroller unit (MCU), H-Bridge driver and opto-coupler is designed to control the EWB’s pinion according to the given rotational input during the experiment. The response measured throughout the experiment is the gapping displacement of the brake piston, clamping force and also brake torque of the EWB mechanism. The responses of the actual EWB mechanism obtained from the experiment are compared with the proposed Bell-Shaped curve. The result of the study shows that the response of the Bell-Shaped curve model closely follows the response of a real EWB actuator in term of clamping force and brake torque with percentage of errors less than 10%

Optimal Gear-Shifting of a Wet-Type Two-Speed Dual-Brake Transmission for an Electric Vehicle

In improving the efficiency of powertrain systems and ride comfort for electric vehicles (EVs), the transmission model is required to enable more accessible and more straightforward control of such vehicles. In this study, a wet-type, two-speed, dual-brake transmission system, as well as a new electromechanical clutch actuator, is presented for EVs. A new coordinated optimal shifting control strategy is then introduced to avoid sharp jerks during shifting processes in the transmission system. Based on a state-space model of the electromechanical clutch actuator and dual-brake transmission, we develop a linear quadratic regulator strategy by considering ride comfort and sliding friction work to obtain optimal control trajectories of the traction and shifting motors under model-based control. Simulations and bench tests are carried out to verify the performance of the proposed control laws. Results of the proposed coordinated control strategy show that noticeable improvements in terms of vehicle jerk and friction energy loss are achieved compared with an optimal control scheme only for the shifting motor as the input

Aeronautical Engineering: A special bibliography with indexes, supplement 62

This bibliography lists 306 reports, articles, and other documents introduced into the NASA scientific and technical information system in September 1975

Modelling and control of a fixed calliper-based electronic wedge brake

This paper presents a new design of an electronic fixed calliper-based wedge brake system. The movement of both sides of the brake piston is activated by a wedge block mechanism. The proposed fixed calliper-based electronic wedge brake system is a class of hydraulic-free device. The mechanism consists of two sets of wedge blocks, a ball screw drive shaft, a sliding beam and an electric motor. In this mechanism, the rotation of the shaft of the electric motor is converted into linear motion by using a ball screw drive shaft while the linear motion of the drive shaft will force the sliding beam to be displaced linearly. This will activate the wedge mechanism, which will cause the pad to be displaced tangentially to the disc brake. The movement of the pad in pressing the disc will generate clamping force and produce brake torque when the wheel rotates. In this study, the mathematical model of the system that generates the clamping force was identified. The model was based on a second order transfer function. The proposed mathematical model was then validated experimentally using a brake test rig installed with several sensors and input-output (10) device. The performance of the brake mechanism in term of rotational input of the drive shaft and clamping force produced by the brake were observed. Accordingly, a torque tracking proportional-integral-derivative (PID) control of the system was proposed and studied through simulation and experiment. Comparisons between experimental results and model responses were made. It is found that the trend between simulation results and experimental data are similar, with an acceptable level of error