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This paper focuses on clamping force control of electronic wedge brakes without additional sensors for cost-effectiveness and system simplicity. Brake-by-wire systems can be used for enhanced, safe braking of intelligent and environmentally friendly vehicles such as gas-electric hybrid and electric vehicles. For implementation of the electronic wedge brake, the clamping force should be controlled properly even though model uncertainty and parameter variations exist due to the environment or system characteristics changes, e.g., temperature variations, pad wear, and nonlinear friction. In this paper, the electronic wedge brake is modeled to include the wedge dynamics as well as the nonlinearities such as backlash and friction in mechanical connections and clearance between the brake disk and pad. An on-line status monitoring algorithm using the simplified mathematical models is designed to estimate the mechanical system parameters.

The purpose of this work is to develop a rollover prevention system with Unified Chassis Control (UCC) which consists of CDC (Continuous Damping Control) and ESP (Electronic Stability Program). Although CDC system contains anti-roll control logic to reduce roll angle, it is insufficient to prevent rollover. ROP (RollOver Prevention) control logic of CDC enhances rollover prevention by controlling damping force distribution to each damper when impending rollover is detected. ESP system also needs the additional control logic for rollover prevention since it is ultimately developed to enhance the stability of a vehicle by controlling its yaw characteristic. UCC system modifies rollover prevention control logic of each system by sharing sensor information. In this study, the rollover prevention effect of UCC system is investigated by simulation and vehicle tests.

This paper describes the development of Mando's new continuously controlled semi-active suspension system. The goals for the new system are 1) enhanced control performance and functionality for customer satisfaction and added value, 2) optimal design of variable valve for compact size, light weight and fast response. Based on the system requirements established from benchmarking and market needs, design of variable dampers, an ECU, sensors and control algorithms is carried out. Skyhook control is applied with a better road detection algorithm by using vertical wheel G sensors. New “Comfort” mode biased toward smooth ride adds more value to the vehicle. Co-operation with ESP helps increase the vehicle stability. Well-defined design procedure and test methods for verification and validation are followed. Simulation study, rig and vehicle integration test prove that the design goals are met.

The semi-active damping control system with continuously variable shock absorber is widely used to improve the vehicle dynamic characteristics such as ride comfort and driving safety. To achieve better vehicle performance, the continuously variable shock absorber must have a fast response time with wide range of damping force variation. In this paper, the analytic model is developed to estimate the effect of various parameters on dynamic behavior of the variable shock absorber, such as electromagnetic properties of solenoid, vibration of moving valve body and pressure prevailing time at damper stage due to compressibility of oil and container. By analyzing the derived model and carrying out the parametric studies, the response time of the shock absorber was reduced and it was verified by rig test.

This paper presents the integrated chassis control (ICC) system under development at MANDO. By sharing the sensor and control information through the communication link among the existing 2 or more chassis subsystems, the integrated chassis control system improves vehicle performance and reduces cost for the sensors and related wiring. ICC consists of continuously variable damping control system(CDC), rear toe angle control system(AGCS) and electronic stability program (ESP). In ICC, the steering angle and yaw control information of ESP are delivered to the other systems through the CAN interface, and co-operative control strategy overrides each subsystem to improve the vehicle handling performance and stability. The effectiveness of both integrated chassis control systems are illustrated by a computer simulation and vehicle test on dry asphalt, snow road surface and so on.

This paper describes the MANDO MGH ESP (Electronic Stability Program) and consists of the control philosophy, hydraulic actuator and the simulation and test results. The ESP system controls the dynamic vehicle motion in the emergency situation such as the final oversteer and understeer and allows the vehicle to follow the course as desired by the driver. The MANDO MGH ESP is integrated with the existing MANDO MGH ABS/TCS, which is improved with the more information and controls both brake pressure and engine torque for the optimal performance. The look-up tables are emphasized to have the accurate target yaw rate of the vehicle and obtained from vehicle test for the whole operation range of the steering wheel angle and vehicle speed. The wheel slip control is applied for the yaw compensation and the target wheel slip is determined by error between the target yaw rate and actual yaw rate.