A gripper tool for OLA & Jubilee - Part 1

After a couple years, this project has finally received my attention.

Tracker: https://gitlab.com/groups/open-la/-/epics/20

Background

I want a gripper tool for this lab robot: https://docs.openlabautomata.xyz/

Notable previous works include:

• BioPick by dr3y at GitHub.
• Also the awsome SO-ARM100 by TheRobotStudio.
• Source Robotics' pricey gripper tool for the Parole.
• Several others at the GOSH forum.

Some requirements

1. Gripping action: for tiny (e.g. seeds) and medium-sized stuff (well-plates and petri dishes). Nothing too heavy.
2. Wrist action: with unbound spinning angle.
3. Affordable, ubiquitous components.
4. Mostly 3D-printed parts.
5. Upgradable.
6. Open-source hardware.
7. Synchronizable motion.

Nice to haves:

• Eccentric grip.

Implementation

• Hollow-shaft concept: a pair of concentric shafts transmit force to different parts of the actuator.
  • The broader shaft (8 mm) rotates the wrist.
  • The narrow shaft (5 mm) passes through it, and actuates the gripper claws.
  • Because of this arrangement, the wrist is coupled to the grip action. Both motors will need to turn in sync for the claws to rotate and hold a certain grip.

Proof of concept

Here is a video of it running clumsily on a pair of servos: https://www.youtube.com/watch?v=_W5kAROLW5M

Up next

Get involved. Introduce yourself and browse to the OLA tools forum.

Get in touch, join the chat! https://discord.gg/GmCeXTHpM4

A roadmap:

• Replacing the servos with NEMA8 motors.
• Print a Jubilee-style tool mount.
• Add endstops, probably optical, probably coupled to each other (or with just one).
• Figure out kinematics for rotation & gripping.
• Have a little fin with it.
• Integrate to the OLA lab automation stack as a new tool: https://gitlab.com/open-la

There will be a "Part 2", no ETAs though. :)