View Single Post
  #18   Spotlight this post!  
Unread 13-01-2013, 21:53
ehochstein's Avatar
ehochstein ehochstein is offline
Coach, Volunteer & Mentor
AKA: Evan Hochstein
FTC #5943 (ESGM)
Team Role: Coach
 
Join Date: Jan 2009
Rookie Year: 2007
Location: Bloomington, Minnesota
Posts: 933
ehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant futureehochstein has a brilliant future
Re: Andymark Pneumatic wheel problems

Quote:
Originally Posted by Ether View Post
A number of questions immediately spring to mind:

1) what does "60% speed" mean? 60% of the motor's rated free speed (in which case how did you measure the speed)? 60% command to your motor controller? 7.2 volts from a DC power supply? or something else?

2) what motor were you using, and what gear ratio?

3) you said "wheel" and not "wheels". Is this a single-wheel linear shooter? or a curved chute shooter?

4) were you using the same model and size pneumatic tire as R3D? or something else?

5) how do you know the speed of the R3D shooter? I couldn't find that info anywhere. could you post a link please.


edit:
I just now saw your video. Whole lotta slippin' going on as the bee exits. Have you tried slowing down the wheel?



1) 60% command to the motor controller, I can measure the voltage tomorrow.

2) CIM direct drive

3) See video http://youtu.be/7dN1thFqr7k

4) We used this wheel which I believe R3D used, I cannot confirm they did.

5) I do not know the speed, I was using the assumption from a previous poster.

The slipping is caused by not having enough tension between the wheel and the side of the arc. The wheel is as deflated as we could get it in this video. This prototype was designed for an 8" rubber wheel
so that is what caused the extra space. Tomorrow I am setting up my velocity reader, another mentor is modifying the wheel to be more effective (I don't specifically remember how) and we will be remounting the wheel closer to the arc.
__________________
Minnesota FIRST Senior Mentor | 2013-?

Stratasys Applications Engineering Technician | 2016-?

2009 Regional Win – 2470 @ 10k Lakes (Thanks 2826 and 1714)
2013 WFFA Recipient – 2470 @ 10K Lakes
2016 Ri3D: 'Snow Problem Reveal
2017 Ri3D: 'Snow Problem Reveal

The opinions expressed above are the personal opinions of the author and do not necessarily represent the views and opinions of any organization the author is affiliated with.