need some urgent help (REPOST)

Posted by Anton Abaya at 2/17/2001 4:37 AM EST

Coach on team #419, Rambots, from UMass Boston / BC High and NONE AT THE MOMENT! :(.

hi guys, its me again asking for some advice.
we have a fork lift mechanism with the pistons and we have been able to lift a battery easily with them (15lbs).

today, we went to the quincy scrimmage and it was unable to lift the bridge using the counterweight on the side of the bridge.

the quincy fellows said their bridge was an inaccurate judgement with regard to its pivot point being as smooth as the ones at the competition.

15lbs. we can do that, but it didnt work there. Should we ditch our pneumatics that couldnt lift it, and build something else to replace it immediately? or is 15lbs plenty plenty to lift the bridge?

what do you think? please help…esp the smart fellows in here.


ps. we have no machine shop access this entire weekend and will have to mockup something with power tools. i know i can do it…3 days.

Posted by Tim Gates at 2/17/2001 7:08 AM EST

Engineer on team #288, RoboDawgs, from Grandville High School and X-Rite/Delphi.

In Reply to: need some urgent help (REPOST)
Posted by Anton Abaya on 2/17/2001 4:37 AM EST:

A description of your mechcanism would be helpfull. What bore dia. are you using? I can’t imagine 15lb force is all your getting from a design similar to a fork lift unless you are pivoting an arm with the cylinder and the cylinder is closer to the pivot point than the load. We are using a 2" bore cylinder and with 60psi even on the rod side of the cylinder you have 170lbf., and we are also using a 2.25:1 advantage which gives us even more force. Post a description of your mechanical device, a sketch maybe.

Tim Gates