An Ethercat Based Real-Time Control System Design for Wheelchair-Mounted 6dof Assistive Robotic Arm

Abstract

Numerous assistive robots for individuals with disabilities have been produced over the past ten years, but researchers have not completely exploited these robotic technologies to enable people with impairments to live independently, especially in respect to activities of daily living. (ADLs). For people with impairments, an assistive system can help them fulfill the requirements of typical ADLs. Assistive robots can help address future healthcare demands due to a growing need for caregivers, a scarcity of them, and an increase in the number of the elderly and people with disabilities. Enhancing functional independence while creating a superior human-machine interaction is one of the most important considerations in the design of these assistive technologies. Current solutions are not considering the new technologies like the EtherCAT field bus that brings better response times and modularity allowing to perform a broader range of ADLs. Thus, the objective of this research design a Real-Time Control Platform (RTCP) based on EtherCAT while integrating multimodal control method for robotic self-assistance that could help individuals with disabilities in performing self-care tasks daily. In this research, a control framework using joysticks seamlessly control a wheelchair and a wheelchair-mounted robotic arm. Custom circuitry was developed to connect the RTCP with the powered wheelchair. Multiple experiments were conducted to test the robotic system. The control method has been tested rigorously, maneuvering the robot at different velocities. The round-trip delay we set between the commands while controlling the assistive arm was 500 us. Tests performed showed that the proposed control system allowed individuals to perform some ADLs such as picking up and placing items with a completion time of less than 1 min for each task.