Having trouble with supporting arm

Hey guys so our team currently wants to add a supporting arm to our throwing arm and we are having trouble. We are a back dumper and are utilizing a gear system of 12-60-12-60. So the supporting arm kept on getting stuck on a gear or axel and prevent our throw arm to fully extend, does anyone have a idea to how to make it work? any pictures or video would be highly appreciated thanks!


A picture would be helpful, I’m having a hard time imagining your problem.

I think that’s our line. You can’t have pictures of what to change until someone understands what you have and how it’s failing to meet your expectations.

What he said.

we have some! in the picture the supporting arm (lower arm) would only be allowed to go to a certain distance which limits our throwing arm to go up n dump.


This is what I would recommend. Setting pieces at angles like you have there doesn’t work.
Also, how many motors do you have on your lift? I only see one.
Screenshot 2017-02-15 at 9.51.57 PM.png

We have motors on the 12 tooths. 12-60-12-60 is our gearing ratio. We tried doing it parallel like you had in the picture but it doesnt work.

I would highly recommend having more than 2 motors for your arm. Adding additional motors will give you significantly more speed and torque when you go to score an object.

This is a good start, but it may not lead you towards where you want to be with a backwards dumper. Mess around with the placement of the joint and see what works for you

How freely swinging is the supporting arm?

We have a backwards dumper too. If it would help I can send a picture of the arm and how we have that set up.

I was going to say that. Currently we have 3 on each of our 2 arms.

@AirplaneManiac Currently my team has 2 motors per side, with a gear ratio that allows us to lift 1 cube or 4 stars (I forget exactly what it is). We only use 10 motors however, and we could put an additional motor on each side if we really wanted to.

OP I would recommend a minimum of 4 motors be dedicated to your arm.

we have 3 motors on each gear tower so a total of 6 (pictures were a prototype). Were gonna try to create more distance between the main arm and the support linkage. Planning on either adding more idlers or drive them separately so that 2 motors are driving the main arm and 1 motor is driving the linkage independently.

Pictures of yours might be useful to give us a reference

https://vbots-octopi.wixsite.com/home?lightbox=dataItem-iz5ukck4 arm…
Gifs(Kind of like video…): https://vbots-octopi.wixsite.com/home/gifs
I hope this helps.