Posted by Frank Toussaint, Engineer on team #111, Wildstang, from Wheeling and Rolling Meadows and Motorola .
Posted on 5/12/99 5:24 PM MST
There is a tremendous learning curve for these robots.
Why not help the rookie teams by shipping them a motor,
a speed controller, the controller board, a set of RNets,
and a joystick as soon as they sign up in the autumn?
Let 'em start learning about these items ahead of time.
Posted by MaryEllen, Other on team #180, S.P.A.M., from South Fork and Martin County High Schools and UTC/Pratt & Whitney, FL.
Posted on 5/12/99 8:04 PM MST
In Reply to: Let’s make it easier for the rookies posted by Frank Toussaint on 5/12/99 5:24 PM MST:
: There is a tremendous learning curve for these robots.
: Why not help the rookie teams by shipping them a motor,
: a speed controller, the controller board, a set of RNets,
: and a joystick as soon as they sign up in the autumn?
: Let 'em start learning about these items ahead of time.
Good idea. It’s tough enough getting organized the first year.
My own personal favorite idea is to have new schools ‘adopted’ for one year
by an experienced team to let them learn. Then cut them loose the second year.
With the understanding that they ‘adopt’ a school their third or fourth year.
Until the school district is saturated.
ME
Posted by Dodd Stacy, Engineer on team #95, Lebanon Robotics Team, from Lebanon High School and CRREL/CREARE.
Posted on 5/13/99 10:17 AM MST
In Reply to: Let’s make it easier for the rookies posted by Frank Toussaint on 5/12/99 5:24 PM MST:
This is an outstanding suggestion. I hope you will post it directly to FIRST. The components would need to be accompanied by a brief writeup with appropriate cautions to protect the controllers. I’ll bet Eric would save himself a lot of heartburn in January and February by following your suggestion.
Dodd
Posted by Joe Johnson, Engineer on team #47, Chief Delphi, from Pontiac Central High School and Delphi Automotive Systems.
Posted on 5/13/99 7:22 PM MST
In Reply to: Let’s make it easier for the rookies posted by Frank Toussaint on 5/12/99 5:24 PM MST:
And, we might as well tell them the awefull truth about those drill transmissions:
It is very tricky to get a reliable connection to that threaded shaft
Remote shifting from high to low and from low to high seems like it is easy, but again, it is very tricky. Infact, while I have heard of teams that have done it, I have never heard of a team that didn’t hear that fateful whine of shifter stuck in no man’s land!
Get those anti-backdrive pins before they get you.
Finally, It would be nice if FIRST sort of hinted at a gear ratio that is ‘within reason.’ Even some advice as simple as ‘your robot should not be able to out run you’ and ‘you should not be able to out walk your robot walking heel-toe-heel-toe’ would be nice.
Perhaps someone would like to write a whitepaper on the topic?
Joe J.
Posted by Jerry Eckert, Engineer on team #140 from Tyngsboro, MA High School and New England Prototype/Brooks Automation.
Posted on 5/14/99 12:58 PM MST
In Reply to: the aweful truth about drill transmissions… posted by Joe Johnson on 5/13/99 7:22 PM MST:
: 3) Get those anti-backdrive pins before they get you.
What is the problem with the anti-backdrive pins?
- JerryPosted by Joe Johnson, Engineer on team #47, Chief Delphi, from Pontiac Central High School and Delphi Automotive Systems.
Posted on 5/14/99 7:45 PM MST
In Reply to: Re: the aweful truth about drill transmissions… posted by Jerry Eckert on 5/14/99 12:58 PM MST:
As to those anti-backdrive pins:
We broke a bunch of those transmissions from the impact load put on the tabs on the last carrier stage of the drill transmissions.
The anti-backdrive mechanism locks up almost instantaneously causing pretty large loads on the tabs. Also, one side of the robot will be more likely to break than the other because the Bosch put larger tabs in one direction than the other (because most uses of a drill involve clockwise rotation of drill bits and screws).
Finally, I like to be able to roll our robot around rather than dragging the wheels.
Joe J.
Posted by Kit Gerhart, Other on team #45, TechnoKats, from Kokomo High School and Delphi Delco Electronics Systems.
Posted on 5/14/99 9:28 PM MST
In Reply to: the aweful truth about drill transmissions… posted by Joe Johnson on 5/13/99 7:22 PM MST:
We have used the drill transmissions for the four years
I have been on our team, and with generally good results.
We have connected to the output of the gear boxes with a
sleave having the same thread as the gear box output, and
then ‘pinned’ with an 8-32 bolt. This year we even had
a gear shift using the servos to move the shifting fork.
We used software to apply minimal power to the motors to
make sure the gear boxes were engaged before returning to
normal operation.
The ~3/1 ratio of high to low gear ratios is a wider range
than would be optimum for our purposes, but for us at least,
it was better than using only one ratio. We were able to
get to the puck quickly in high gear and then shift to low
to push the puck, defend, or whatever. If the transmissions
are securely in gear, they are very reliable. We have only
broken one in my four years if FIRST.
Also, the drill cases, if everything is aligned well, are a
good way to hold the motor and transmission and take the torque
reaction. This year we did not use the drill cases, but
mainly to save space.
Posted by Daniel, Student on team #192, Gunn Robotics Team, from Henry M Gunn Senior High School and NASA Ames.
Posted on 5/15/99 12:33 AM MST
In Reply to: Re: the aweful truth about drill transmissions… posted by Kit Gerhart on 5/14/99 9:28 PM MST:
: Also, the drill cases, if everything is aligned well, are a
: good way to hold the motor and transmission and take the torque
: reaction. This year we did not use the drill cases, but
: mainly to save space.
True, but the drill cases are terrible with heat and are really inaccessible when you burn a motor. Those things can be more trouble than they’re worth.
Posted by Dodd Stacy, Engineer on team #95, Lebanon Robotics Team, from Lebanon High School and CRREL/CREARE.
Posted on 5/15/99 8:58 AM MST
In Reply to: Re: drill cases posted by Daniel on 5/15/99 12:33 AM MST:
: True, but the drill cases are terrible with heat and are really inaccessible when you burn a motor. Those things can be more trouble than they’re worth.
Hmmm, maybe time to think about gearing and cooling for next year’s 'bot?
Dodd
Posted by Daniel, Student on team #192, Gunn Robotics Team, from Henry M Gunn Senior High School and NASA Ames.
Posted on 5/15/99 11:36 AM MST
In Reply to: Re: drill cases posted by Dodd Stacy on 5/15/99 8:58 AM MST:
Wouldn’t you say the best system would take advantage of all factors? Those motors need room to vent. The more exposed surface you have, the more effective that muffin fan is going to be anyway. This gives you more flexibility for your gear ratio.
Those drills just aren’t meant for the kind of stresses involved with this game. They’re designed to be used for brief intervals.
Maybe I’m just confused though, I’m only a high school student =)
-Daniel
Posted by Mike King, Other on team #88, TJ², from Bridgewater Raynham and Johnson & Johnson Professional.
Posted on 5/14/99 11:16 PM MST
In Reply to: the aweful truth about drill transmissions… posted by Joe Johnson on 5/13/99 7:22 PM MST:
: Finally, It would be nice if FIRST sort of hinted at a gear ratio that is ‘within reason.’ Even some advice as simple as ‘your robot should not be able to out run you’ and ‘you should not be able to out walk your robot walking heel-toe-heel-toe’ would be nice.
Hey, first year of TJ², we used seat motors to drive the robot!
Mike
(There was an extremely logical reason for that particular desicion.)
Posted by Kate Leach, Student on team #166, Team Merrimack, from Merrimack High School and Unitrode / RS Machines.
Posted on 5/15/99 9:01 PM MST
In Reply to: Re: the awful truth about drill transmissions… posted by Mike King on 5/14/99 11:16 PM MST:
‘There was an extremely logical reason for that particular desicion.’
Care to share this extremely logical reason??? 
Posted by Mike King, Other on team #88, TJ², from Bridgewater Raynham and Johnson & Johnson Professional.
Posted on 5/15/99 11:33 PM MST
In Reply to: Re: the awful truth about drill transmissions… posted by Kate Leach on 5/15/99 9:01 PM MST:
: ‘There was an extremely logical reason for that particular desicion.’
: Care to share this extremely logical reason???
Sure.
It was our rookie year.
Is that enough? 
The game was Hexagon Havoc. (gather the small balls, and the 2 large balls and put them in the goal)
First let me say I was not on the build team, so i don’t know all the particulars. (couldn’t make the time commitment 
)
The only way we could get our ball collector, and our scissor lift (one of the first used in FIRST) to work, was to use the drill motors to power them. We were one of those teams that showed up early just so we could finish building our robot.
Ahh to be rookies again. (NOT). We had such troubles with our mechanical subcomponets, we never really had time to program the brain. In fact, we jury rigged our own speed controler, using Reed switches and Servo’s. FIRST Didn’t like that, (12V at how many AMPs thru switches designed for What?) The guy said if they had a most creative rule infraction award, we would have got it, then he showed us how to program the brain. It still was great competion. We placed 25th out of 47 teams, won best sportmanship, and got to see the HoverCraft Placebo! Not bad for our rookie year.
Mike King
'96 Driver
'97-'98 Cheering Fan
'99 Webmaster
Posted by Mike King, Other on team #88, TJ², from Bridgewater Raynham and Johnson & Johnson Professional.
Posted on 5/15/99 11:35 PM MST
In Reply to: Re: the awful truth about drill transmissions… posted by Mike King on 5/15/99 11:33 PM MST:
Picture didn’t attach. Must have typed the link wrong.
Posted by Jake Mazotas, Other on team #177, Bobcats Robotics, from South Windsor High and International Fuel Cells.
Posted on 5/16/99 8:40 PM MST
In Reply to: Let’s make it easier for the rookies posted by Frank Toussaint on 5/12/99 5:24 PM MST:
I don’t really like the idea of putting tips in the rules for rookies, but I think it would be a great idea for FIRST to make a guide for rookie teams. It could contain stuff like…how fast the robot should move, help with the controls, etc. I’m sure somthing of this nature could help.