Design And Research Of Four Wheel Moving Vehicle

With the rapid advancing of electronic technology,automation technology and artificial intelligence,the demand for mobile devices has increased rapidly as well.The application fields have evolved from the initial processing and manufacturing to the fields of seeking assistance,exploration,construction,service,and medical care,and the steering flexibility requirements for moving platform are increasing.In order to be able to work in some complex environments,it is of great significance to study the mobile chassis and detection vehicle which can flexibly steer.This paper takes a four-wheeled mobile cart as the research object,the structure design of the mobile car is carried out and the motors are controlled,the steering motor angle control and hub motor speed control are realized.First of all,the overall scheme of the mobile cart was designed based on the analyzing of various structures of mobile carts.The key parts are parameterized by satisfying the four wheel independent steering and independent driving function,which simplifies the structure of the parts.And the assembly and commissioning of the physical cart is completed in the laboratory.Secondly,kinematics analysis was performed on the four-wheeled mobile platform cart.On the basis of the four wheel independent steering structure,the relationships between the physical quantities are calculated by analyzing the same direction steering,reverse steering and in situ turning working conditions.Then,the mathematical models of the brushed DC steering motor and brushless DC hub motor are established.The transfer function of hub motor speed control is solved.The optimal solution of three parameters of the PID controller of hub motor is solved based on adjusting by glowworm swarm optimization.The optimal solution of the three parameters are brought into SIMULINK model.The speed response diagrams of the motor at different target speeds are simulated by the model,and the control strategy of the whole vehicle is proposed based on the status of the cart in the lateral,oblique and straight line running.Finally,the hardware part of the control system is elaborated,and the development environment CCS6.0,the development process and program design ideas are described.Based on these,the motor control scheme is planned and designed.The 1/4 vehicle’s DC steering motor experimental platform and wheel hub motor experimental platform are set up to carry out experiments of DC steering motor rotation angle control and wheel hub speed control.The related signal waveform curves in the control process are observed,and the evaluation conclusions are given.