Investigation of Propeller Control Method Focusing on Reverse Force Input for Collision-Free Arrival Motion of Ship

In this paper, a novel controller design focusing on reverse input using propeller thruster such as air plane taxiing and ship for collision-free arrival motion was proposed and evaluated in mock up model. And ultimately, it is necessary to control the position, attitude and speed at the same time. The operation of docking at a port has not yet been automated by machines, and is known as a special skill that requires the concentration of craftsmen. In our study, to aim at automating accurate docking and berthing operations in ship control, we used an airplane-type model with a propeller, which is relatively easy to test, rather than a test environment using water, where the effects appear three-dimensionally, and the reaching motion characteristics on the ground were investigated. In this process, we focused on the reverse motion often employed when the craftsman controls the ship. We developed two types model devices of ground taxiing airplane and ship, and perform the reaching movement experiment by normal P, PD control and human's visual feedback control also performed. As a result, in order to rapid approach without overshoot, the applied thrust for a constant time period gave relatively good results, and it was possible to control stably even though it was necessary to search for parameters. By comparing with a human control by pressing keyboard button method using a reverse force input, it also relatively good result, and by introducing the human reverse force input way to the thrust for a constant time period method, it could realize rapid and stable controlling. As a basic study, we developed a simple ground taxiing airplane model and U-shaped guided model ship to realize a rapid, non-overshoot and stable reaching movement. The difficulty of the reaching movement would be mainly occurred by propeller / screw type thruster control difficulty, however, by using a human control way of using reverse force input, we found some reaching movement performance improvement even though using a constant time period forward / reverse force input controller.