Improvements for Power-assisted Three-wheel Carrier Cart With Stair-climbing Ability

Carts and carry bags are used to transport goods, however, they place a heavy burden on the user especially when ascending or descending stairs. Crawlers, often used for mobile robots, suffer from slippage on stairs. The driving unit of proposed cart with power-assist has a planetary gear mechanism with three drive wheels on each side, and it can move on a plane by rotating the wheels and climb stairs by rotating the arm part. Although the burden of the user was reduced at both flat floors and stairs, there was a problem of poor operability for descending stairs. In this study, we propose a new power-assist control method to solve the problem in descending stairs and evaluate the method through experiments.