Underactuated Adaptive Robot Gripper Finger, v1

Here’s what I’ve been working on today. R&D is a long, difficult process, but I like a challenge. Case in point, I’ve been stuck on trying to design a 6DOF robot arm for ages. It occurred to me that I’m starting at the shoulder and trying to work towards the hand. What if I start at the hand and work back toward the shoulder? So I’m making a robot gripper inspired by Robotiq’s 2 and 3 finger grippers. They’re underactuated because they have fewer motors than degrees of freedom and they’re adaptive because they can deal with gripping odd shapes.

printing underactuated adaptive gripper finger, v1

This was a failed print. I printed six tests before I got two that worked, and stopped in the middle to check a few potential problems. My 3D printer needs a lot of good lovin’ to work. Still worth it.

underactuated adaptive gripper finger, v1

Here’s a close up. The strings will probably be replaced with 50lb fishing line. There’s one on either side running down the groove in the middle of the finger.

underactuated adaptive gripper finger, v1, size comparison

Here it is again, to scale. I’ll probably reprint each “bone” as a single piece, rather than two separate halves. I still need a way to keep the strings in place and to add some touch-sensitive pads to detect contact. I also need to hook these to a servo and make at least one more. All in all I’ll be lucky if I get a beta working in less than 6 prototypes.