The Robot Claw Project
Over the course of a couple of months, I decided to design and build a 3D-printed robot hand claw. It wasn’t easy, as there were multiple failures. However, they helped to improve the end product. It was a significant learning experience for me.
In the beginning, I tried experimenting with design options using the Lego mechanic kit. Earlier I thought of using three gears. One wheel was connected to the motor in the middle, and the other two were connected to the two claws.
I then realized, that you needed at least 4 wheels to get this working to get the claws to go in the opposite directions (to open and close). The design seems bulky, and I decided to try another approach.
My dad suggested using a mechanism like in grab toy (https://www.hobbylobby.com/Crafts-Hobbies/Kids-Crafts-Activities/Games-Toys/Grab-It-Claw/p/80902783?gclid=CjwKCAjwi6WSBhA-EiwA6Niok0Y0gC1j4Bka-ODxglFjDvKiTQLnAgV4ipjXssKM2ofUc-Wtg7g5fhoCtlsQAvD_BwE)
I drew a possible design for the claws that took inspiration from the in & but I needed a mechanism to push the two internal arms in and out.
My dad suggested using a nut and a bolt to help with the movement, as it would provide that push and pull motion. It made the power train simple and I could easily place the motor on the arm part of the claw and avoid a 90-degree power shift with gears.
Getting the claws and the 4 cross arms into perfect size was a trial and error process I had to print 3 versions and each one helped me make a better end result. In some of the designs, I adjusted the width of the grabbing mechanism, the claw.
The final step was assembly. I printed the pieces with a 3D printer and began to assemble the parts together. However, while assembling I realized there were some pieces I could add to make the design better. For example, one such as the switch holder
After several tries, I was able to get it fully working and had a lot of fun grabbing things with my new robot claw.
