Development of automatic barrier detection system for wheelchair

This paper describes a system that detects barriers for wheelchair users, such as level differences and slopes on a road. The system searches out such barriers automatically and records the positions on a digital map. We have been developing the wheelchair that has a 2-D Laser rangefinder, a GPS receiver, accelerometers, rotary encoders and a sphere image camera to use it for detecting such barriers. In our system, proper prediction of condition in which a wheelchair user notices such barriers during riding it is needed. However, the detection was quite limited. In this paper, we added an apparatus, which can measure torque on right and left wheels, into our proposed system. Then the method to predict the condition referring to the torque on the wheels is discussed.