Developed by engineers at the RIKEN institute (Kobe, Japan) and Tokai Rubber Industries (TRI; Komaki City, Japan), the new robot can lift a patient weighing up to 80 kg off floor-level bedding and into a wheelchair, freeing care facility personnel of one of their most difficult and energy-consuming tasks. The original Robot for Interactive Body Assistance (RIBA), developed in 2009, was also capable of lifting a patient from a bed to a wheelchair and back, but functional limitations prevented its direct commercialization.

The new robot, named RIBA-II, overcomes these limitations with added power and functionality. New joints in the robot's base and lower back enable the RIBA-II to crouch down and lift a patient off a futon at floor level, the most physically strenuous task for caregivers, and one that RIBA was not able to do. RIBA-II accomplishes this task using newly developed “Smart Rubber” sensors, capacitance-type tactile sensors made entirely of rubber. Printed in sheets and fitted onto the robot's arms and chest, the sensors enable high-precision tactile guidance and allow RIBA-II to detect quickly a person's weight from touch alone, guaranteeing patient safety.

The robot’s arms are driven by six motors each, which help the robot adjust leverage at any angle of approach to make carrying safe and comfortable for the patients. An interferometer drive mechanism in the arm joints allows two types of bending and twisting movements in one operation, by using a bevel gear mechanism based on two motors using a common differential gear. A haptic guidance system allows intuitive control and guidance by a human operator, via voice guidance or a remote control. In all, each arm has 7 degrees of freedom (DoF), the neck has 3 DoF, the waist has 2 DoF, and the omnidirectional base provides 3 DoF.

In the future, RTC researchers will work together with partner nursing care facilities to test RIBA-II and further tailor it to the needs of caregivers and their patients, while also developing new applications in areas such as rehabilitation. TRI aims to bring care-giving robots like RIBA-II to the market in the near future, promising support for aging populations in countries around the world.

Related Links:
RIKEN institute
Tokai Rubber Industries