23-02-2005 09:37

Bob Steele

Re: pic: Rachel climbs a tree... 1018

This is the Devils' Tower in action...late Monday night...
It seems to be quite steady and smooth in its climb to the heights.
Designed by the Pike RoboDevils' Engineering Team.. and it will be featured at the Boilermaker Regional and at IRI in the summer. (Unless we some kind of $$$ miracle, we will not be able to go to Atlanta...)

Good luck to everyone!!! It was a GREAT build!!

23-02-2005 09:38

Denman

Re: pic: Rachel climbs a tree... 1018

that lifting arm must weigh a ton!
it looks like its bending a little though...
evidently you can reach at least 10 foot, have you ever fallen over?

23-02-2005 09:41

tiffany34990

Re: pic: Rachel climbs a tree... 1018

how fast does the arm go up???

and how heigh does your ceiling go up???

great job though again

23-02-2005 09:42

Mark Pettit

Re: pic: Rachel climbs a tree... 1018

Is that a scale on the floor?
Is it accurate?
Our team needs a better solution for weighing during the build.
What'd that one cost? Brand? Model #?
Incidentally, what does that sweet lookin' machine weigh?

23-02-2005 09:42

Bob Steele

Re: pic: Rachel climbs a tree... 1018

Actually the arm (the horizontal portion) only weighs about 16 lbs. (including the hook and the motor) We don't intend to drive around much with it all the way up in the air. The whole robot weighs in at slighty less than 119 lbs.
The tower and the drive train are NBD... (Nothing but Dewalts...)
Chip motors with Dewalt transmissions... We used a globe motor and a rack and pinion system to move the tower arm...

I believe that the entire robot is simple but quite elegant in its design approach.

thanks
B

23-02-2005 09:44

Stu Bloom

Re: pic: Rachel climbs a tree... 1018

Our final weight is right on target. The tower secitons are cut from .100 thick aluminum sheet and weigh about 10.5 lb each. The arm is another 16 pounds. The tower is raised by one CIM/Dewalt combo using cascading style cables, and the arm is operated by a globe motor with a rack and pinion arrangement. The tower raises to full height (13 feet to the top of the arm) in 4-5 seconds.

23-02-2005 09:45

Bob Steele

Re: pic: Rachel climbs a tree... 1018

The arm goes up relatively fast. We have some difficulty with a tetra getting to the complete height. We will try to optimize that at the regional. But it has gotten high enough to cap a tall goal with 3 tetras on it..( that is the design parameter) The ceiling in that room is around 15 feet or so... It is the only room we could test it in...smile

As far as bending is concerned... the runout on the arm isn't more than about 2-3 inches at full extension... but we will rarely extend it fully either...it is designed to be used at about 2/3 extension...at that point the runout isn't more than half an inch or so...

23-02-2005 09:51

Bob Steele

Re: pic: Rachel climbs a tree... 1018

The scale is a TANITA BWB-800A Class III scale.
We purchased it at the beginning of last year's season... I believe we paid somewhere around $350 for it... maybe less... it was purchased online.
It has come in extremely handy for both FIRST and BEST robotics... it has a top end of 300 lbs and reads to .2 lbs.... We just put a board on top of it and drive or push the robot up on the board after zeroing the board out... works great!!! Every team should have one... We weighed during our rookie year by moving the robot down to the wrestling room (a loooooong way...) and using their scale... now we use this one... and its battery run so we can move it easily... if you need any other info please let me know