The Sapien 6M Intelligent Robotic Arm
Sapien 6M is an intelligent robotic arm from Sarcos Robotics that can lift more than its own weight! Yes, it has a very good strength-to-weight ratio.
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Enhanced for autonomous mobile manipulation, the 44 kg/97 lb intelligent robotic arm is capable of lifting payloads up to 50 kg/110 lb. As you can see in the video below, it can lift an 80-lb dumbbell with ease.
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Everything is embedded in the intelligent robotic arm, and no external control box is required to control and power the robot. Its end-effector interface allows for integrating various end-of-arm tools with no issue.
With six degrees of freedom, the end-effector has precise positioning thanks to continuous wrist and elbow roll joints. In the video below, you can see the Range of Motion (ROM) of this robotic arm.