User Intention Based Intuitive Mobile Platform Control: Application to a Patient Transfer Robot

This study proposes a user’s intuitive intention-based control system for mobile robot platforms. As an application of the control scheme, we focused on a robot that transports patients in medical facilities. However, since most of the people who operate the patient transfer robot (PTR) are not robotics experts, an intuitive control method is needed to enable easy operation of the robot system. Also minimizing the discomfort experienced by the patient in the process of transferring the patient through the patient transfer robot is another important issue to consider. Therefore, the main contributions of this are developing an intuitive user interface and proposing a sway reduction control scheme. To accomplish the first issue, the intuitive control is implemented by proposing a robot control interface, where four force-sensing resistor (FSR) sensors are installed on a robot’s handle (where a user holds a robot). Through this, the robot can be easily moved with only a simple and intuitive operation of the user. Therefore forward, backward, left movement, right movement, left turn, and right turn operation can be controlled through the intuitive movement of the user input through the developed user interface. Additionally, in order to satisfy the second requirement, the patient’s sway reduction strategy is suggested by applying fuzzy logic-based control command generation method to the user intention. Through this method, the sway that occurs during the movement of the robot is reduced. In this study, the mecanum wheel was applied to the driving platform of the patient transfer robot to enable omnidirectional movement. The performance of the proposed control method is verified through simulations and experiments. Simulation and experimental results confirm that the proposed method reduced the acceleration and jerk root mean square values of the robot compared to a comparison method.