Design and implementation of the control system for a physical motorcycle simulator

Abstract

Motorcycles are becoming an increasingly more popular mode of transportation, primarily due to the time savings which can be achieved through their use. However, the number of fatalities occurring in motorcycle-related accidents on the Maltese roads is also increasing at an alarming rate. Thus, the RIDE+SAFE project was envisaged, where the goal was to design and implement a physical motorcycle simulator which can be used to allow a rider to test different configurations of a motorcycle’s features in a safe setting. This simulator could then be used to guide the customisation of a motorcycle according to a rider’s specific needs. This project makes use of a StewartGough Platform to manoeuvre a mock-up motorcycle and rider. Such a simulator requires a complex control system to actuate the Stewart-Gough Platform with movements which ensure that the rider experiences motions that simulate the true sensations typically experienced during a real motorcycle ride. This is obtained by the use of a so-called motion cueing algorithm, which exploits the vestibular sensory system of the human body. In addition, one needs to ensure that the platform does not exceed its physical limitations of motion. Two approaches were taken when designing the platform’s control system. The first is the displacement mode approach in which the main control variables were the platform’s actuator displacements. By contrast, the second method, called the velocity mode approach, controls the platform’s actuator velocities. Both approaches include a motion cueing algorithm, the inverse kinematics, and a motor displacement/velocity controller. The motion cueing algorithm and the inverse kinematics were similar in both approaches, however, the displacement and velocity controllers differed significantly. This is because the displacement mode approach adopts an outer-loop feedback path within a cascade control architecture, while the velocity mode approach makes use of only one feedback loop for velocity, by relying on the motor drivers’ internal velocity controller to regulate the motor velocity. This dissertation describes the design process and implementation of the motion control system for the platform of the physical motorcycle simulator. Results, achievements, and limitations of the final set-up that was developed by the end of this project are analysed and discussed. Finally, suggestions are proposed for the development of a custom solution that could be implemented to complete the implementation of the simulator’s control system.