Hand Testing and Performance

The video below is an excerpt from Erin Kennedy's February 2015 Robot Party. The Robot Party is an online community of robot makers who share their projects and discuss robotics ideas. In the video I demonstrate the manual and programmed modes of operation, and discuss the performance of the gripper.

Gripper Performance

As a practical gripper, the hand has very limited use. The fixed position of the fingers makes it much less flexible than a human hand, while the soft materials make it much less precise than a traditional robotic gripper. In effect... the worst of both worlds!

The hand can hold light objects like a ball or a light weight hand tool. It could be attached to a larger robot arm as an end effector, and used in situations where precision and grip strength are not as important as having a gentle, compliant grip.

Gesture Performance

Much of human communication is non-verbal. By using gestures that humans are familiar with, a robot can elicit an emotional response. For example, different responses from an observer are likely if the robot is gently waggling its fingers, taping impatiently, imitating a rude gesture, or ominously counting down.

Programmed Mode

In programmed mode, the several gestural positions and programmed motions can be amusing, and are instructive as an example of what soft robotics can do. Additional positions and motions can be programmed as well.

Manual Mode

When operating in manual mode, the frequency of the Pulse Width Modulation (PWM) used to control the air valves can be changed via a potentiometer. The frequencies used are in the audio range and sound is emitted by the coils of the air valves during use. The frequency also visibly alters the movement of the fingers from a stuttering motion to a fairly smooth motion.

Within the limits of the freedom of motion, the hand can be made to "dance" and "sing" along to the control of an operator, which can be somewhat entertaining.