The Claw

So this week my main objective was to get the claw mechanism working properly. With my servo having not arrived, I borrowed  another one for the time being with the same dimensions. I had to file the middle section a little but it fitted just fine.

I printed out the mechanism supports on the 3d printer, with 100% infill to make it strong and assembled it in the current bot. With the servo connected to the arduino, I figured out the maximum opening and closing points and wrote a quick program that opened and closed the arms.

This worked fine, although in my first attempt I accidentally soldered the ground pin of the servo to the reset pin on the arduino! However, at that time I was still working with the original MDF claw that I made for my first prototype. I decided that now was the time to try and make the new claw (which I designed a while ago) out of steel.

After a chat with a workshop staff member, I found the best way to do this would be to use the university's hot wire cutter. However, being the most used machine in the workshop, there is a long ( about one month) waiting list. This is completely fine however as the actual robot wars is not till December. I submitted the work order and 3d printed the claws so I would have something to show off for the time being. When the steel claws are ready, it would be a simple job of bolting them in place.

With these printed, and a servo with more torque installed, I had a completed claw mechanism. It seemed very strong. With some simple testing, I found it could easily lift a 500ml bottle of water, which equates to a weight of 500g. Seeing at antwieghts are 150g at most, I should easily have the grip to move them. Also, the newer design of the claw is much gripper and grab objects better than the other one.

Video of claw meachnism