Closing the loop in a treadmill-based 2- wheeler simulator: Development of a Communication Bridge and PI-Controller for a Treadmill

Sammanfattning

This thesis project aims to further develop an existing simulator that uses a largescaletreadmill from Rodby AB as a driving platform to simulate a real drivingenvironment for 2-wheeled vehicles (e-scooter). To keep the vehicle centered on thetreadmill a rope is attached to the vehicle, which introduces unwanted interference.Additionally, a motion capture system from Qualisys AB is used to track the movementand position of the rider. This serves as a controlled environment to studybehaviors of riders on 2-wheeled vehicles, such as riding under the influence of alcohol.For a more realistic simulation, a closed-loop control system that adjuststhe speed of the treadmill based on the position of the e-scooter was implemented,replacing the rope. The objective of the project was to stabilize a 2-wheeled vehicleat the center of the treadmill without the use of physical restraints. Positionmeasurement was implemented using high precision Qualisys optical motion capturesystem that transmits position information in the 6 Degrees of Freedom (6DoF) inreal time to a custom control system built in Python.A custom Proportional-Integral (PI) control logic was implemented to calculate andcontrol the speed of the treadmill depending on the riders position. It was ableto adjust the speed of the treadmill depending on the riders position but was notfast enough to keep the rider centered on the treadmill when the rider acceleratedaggressively, due to the treadmills limited acceleration capabilities compared to thee-scooter. In addition to software latency which further slows the system. Furtherdevelopment is required for the control system to operate accurately to simulate areal driving environment for 2-wheeled vehicles.