Budget-Constrained Robotic Claw Arm
Project Overview
A team of 4 of my friends and I designed a robotic claw arm for the 2024 APEGA Science Olympics, where our project achieved the Gold Standard! The design problem consisted of developing a budget solution (<$80) that could transport mock produce (plastic balls) from one crate to another. We used recycled materials and basic circuit elements to build a claw-machine inspired 4DOF claw capable of picking up and depositing objects.
| Design showcase (click for video!) | The team in action |
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Design Process
Our design process involved a lot of collaborative discussion and prototyping. The group met multiple times in the early weeks of the challenge to discuss a solution to the problem that could accomplish the task, use few resources, and most importantly, be awesome. We settled on the claw-machine inspired design as it would be very feasible using a simple wooden structure and strings as tracks.
One of the most difficult elements was finding a claw design that could grasp the balls while maintaining an ultra-simple design. Given our robotic arm design, we knew we couldn’t have too much complexity near the gripper itself, as it would overcomplicate the design given our constrained resources. We made prototypes in my friend’s basement with scissors, cardboard, and hot glue, until we settled on a ‘tendon’ design to close the gripper around the ball.
After making a few design drawings, we built the frame and began experimenting with the optimal actuation mechanisms. We settled on using old thread spools to tension a string, which would help an anchored portion of the arm slide through its range of motion. We connected the motors to centralized breadboards, and began testing!
We tweaked the design to optimize for pickup and transport of the balls, before stylizing it and heading to the competition. Our design successfully picked up balls during the timed test, and while we may have left some on the table, most ended up in the crate (pun intended).
Skills and Tools
I learned about:
- Mechanical design
- Prototyping
- Collaborative design
- Breadboarding
I used these tools:
- Breadboarding
- Woodworking tools