Development of an Intelligent Transport System for EV 2015-01-9132
Japan is suffering from the problem of an ageing society. In Kitakyushu city more than a quarter of people are aged above 65 years. The roads in this region are narrow with steep gradient and vulnerable roadbed. A big ratio of elderly people are living on their own. These characteristics make driving unsuitable. The problem is magnified by infrequent public transportation. A need-assessment survey for an autonomous vehicle at a community event suggested the applicability of small electric vehicle Toyota COMS. The vehicle is then equipped with features like automatic driving and platooning. The autonomous drive system is built to develop an intelligent transport system (ITS) using various sensors and actuators. Stereo camera and ultrasonic sensors were used to get a judgment of obstacle. Google earth and GPS were used to generate the target path using the Bezier curve method and optimized route is chosen. IMU is used for calculation of vehicle position to make a compensation about the route information. White line recognition ensures that the vehicle follows road geometry. A non-linear model predictive controller (MPC) model is developed to control three driving variables, namely, brake, speed and steer angle. Platooning is realized by driving information exchange based on Zigbee communication. The conventional platooning control methods, improve the power consumption by shortening the inter-vehicular distance. In contrast, the proposed method controls the speed at the time of acceleration ensuring enhanced ride comfort for elderly people. The vehicle is modelled using CarSim® and is integrated with the MPC modelled in Simulink®. The mathematical vehicle model is validated by performing an ISO lane change test and the proposed autonomous drive and platooning system is judged using simulation and some field tests.