Manufacturing Equipment Makers Venture into Robot Hands

Amid the proliferation of industrial robots, robot peripheral devices that support various workpieces have been emerging.  Among them include robot hands, and electric/pneumatic gripers. An increasing number of manufacturing equipment and motor manufacturers have been embarking on these products as a new business.  

Japan is witnessing a decreasing birthrate and an aging population. China will also become an unprecedented aging society 20 years from now. The decline in working population is a serious social problem and the trend to use robots for manufacturing is expected to gain momentum.  

The development of robotic peripheral devices has become active, and the commercialization of robot hands and electric and pneumatic grippers has been progressing. Although robot hands and electric/pneumatic grippers have different shapes, they are both attached at the ends of robot arms to perform “pinch,” “grip” and “hold” operations.  

Expands Robot Lineup 

Yamaha Motor Co., Ltd. has been expanding its lineup of industrial robots, focusing on small robots, including vertical articulated robots, horizontal articulated robots (SCARA robots), and single-axis robots. The company has marketed the YRG Series electric gripper, which has achieved high-precision gripping force and position and speed control, and has high affinity with SCARA robots. The gripper can be controlled by a single unit of the RCX240 four-axis controller, eliminating exchanges with upper-stream systems, such as power line communication (PLC), and allows easy setup and start-up.  Gripping force can be set in the range from 30 to 100 percent with an increment of 1 percent. It can grip fragile and easily deformable workpieces, such as glass springs.  

Joint Research with JAXA

THK Co., Ltd. has commercialized TRX robot hand, a controller-integrated general-purpose gripper. It is light and compact and can hold objects of various sizes. The company had conducted a joint research on robot hands with the Japan Aerospace Exploration Agency (JAXA), and supplied the world’s first robot hand, which was operated in outer space in 2012.  The company’s robot hand was used in REX-J project for extra-vehicular activity at Kibo, the Japanese module that forms part of the International Space Station. Thus, THK’s robot hands have played a pioneering role. TRX robot hand can hold objects of various sizes like human hand, and TRX-S has achieved grip diameter of 10 to 100mm.  

Photo 1: Commercialization of robot hands that support various workpieces advances (THK’s demonstration at INTERNATIONAL ROBOT EXHIBITION 2019 held in December).

Makes Inroad into Industrial Robots

Shinano Kenshi, Co., Ltd. has made an inroad into the industrial robot field on full scale, and started market offering of ARH305A robot hand in 2019. The company has commercialized a robot hand as part of the efforts to commercialize robot-related devices through application of positioning technology by leveraging its motor technology. The ARH305A robot hand adopts a stepping motor for its servo system, and is capable of adjusting gripping force in accordance with the softness and hardness of objects. It can also control operation speed and opening and closing positions. ARH305A has been authenticated as UR+, a peripheral devices platform for collaborative robots made by Universal Robots.

Photo 2: Shinano Kenshi’s ARH305A robot hand can control operation speed and opening and closing positions.

CKD Corporation released the FFLD Series thin, long-stroke electric gripper to the market in April. Its main applications include handling of diverse workpieces, holding of workpieces in application at the end of robots, and transfer of small workpieces at the end of orthogonal actuators with multiple axes. The FFLD Series features industry-leading thin size and lightweight, meeting needs for smaller robots. It firmly grips workpieces to accommodate complex and high-speed movements of robots. It features the longest stroke in Japan (one side: maximum of 70mm) and suits diverse workpieces. 

ORIENTAL MOTOR Co., Ltd. released the EH Series electric gripper also in 2019. It features rack and pinion mechanism and achieves delicate “hold” like human’s finger tips.