The Design Of Motion Control System For Automatic Parking Assist

With development of economy in China,vehicle is becoming more and more popular as a common transportation tool.However,the increasing automobile ownership leads to serious traffic jam in the city.It has become a common problem for drivers to hunt for an unoccupied parking space and successfully park the vehicle.Although currently China OEM has Produced different kinds of products with parking assist function,the full automatic parking function is not mature.Motion control is one of the important technology of full automatic parking.The motion control of automatic parking is based on current velocity,acceleration,distance to the end point and so on to make a decision and control the brake system or engine system.In this paper,based on ultrasonic radar products with parking assist function,the vehicle dynamic model is analyzed,the low speed motion control system is designed,finally the full automatic parking function is realized.In order to meet the system requirements,firstly,the vehicle dynamic model is presented,the influence factor of vehicle motion control is analyzed,the system for vehicle motion control is built up in this paper.Secondly,the motion control system architecture is designed and the suitable hardware platform is built up.Then,the design of the vehicle longitudinal motion control is introduced in details,included the design and optimization of the longitudinal distance planning and control strategy,where the polynomial approximate for distance planning and the feedforward with adaptive PI?proportion integral?feedback control are included.Lastly,based on parking assist system,the vehicle motion control system for automatic parking is performed in real vehicle to verify rapid prototype.Here,based on a real test vehicle,the hardware equipment ES1000 is built up to realize rapid prototyping verification,and the software which ran on the ERCOS^EK is based on AUTOSAR structure.The parallel parking and vertical parking conditions are selected for real vehicle experiment.The results show that the designed vehicle motion control system could well complete the automatic parking,the vehicle speed is smoothly controlled,and comfortable driving experience is obtained.