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View Full Version : what happens when you give a nonFIRSTER a robot?


lukevanoort
12-06-2005, 09:21 PM
Okay, I've meant to post this for a while.

At my team's school (I've moved but still participate) there is this thing called Ag day. The Agricultural Department has a fairish thing where the display tractors, tables, chickens, pigs, etc., and all the extra-curricular clubs and teams recruit, and raise money. Now, due to the fact that FIRST is so pricey we don't really focus on raising money, we recruit. So, we decided to have a $1.00 USD price for 1 min of robot driving time, and if you got the highest score of the day you won a $15.00 USD gift cert to Best Buy. We decided to use our easiest to drive robot, OCCAM 2, from '02. At the time OCCAM 2 was just a drill powered RWD box, the goal gripper and ball shooter (CIM driven wheel on a ramp) were disabled for safety reasons. We made a soccer inspired field that was basicly a few 2x4s or 2x6s making low wall about ~10'x8'. One side had a little pocket for scoring old playground balls left over from an earlier year. Well, our first driver utterly failed at scoring since all he did was wheelies, cracking the wood our front casters were mounted on. Then we had a few normal people that were pretty bad drivers, but since most of them had never even heard of tank drive, that's expected. Then we had this one girl, who I think was a school cheerleader, or somebody told me she was. Well I don't think she quite grasped that the joysticks weren't on/off switches and she slammed the robot around in wheelie-turns and into the little wall we had made, then, somehow, she drove over the wall, then back. Somewhere in there she shredded a drill tranny, so all it did was turn, but this girl I don't think was FIRST material, since she didn't realize there was a problem, and kept jerking the one joystick that had an effect. Well, this was getting out of hand and a bit dangerous, so one of our team members (not me, I'm not brave enough) jumped on the robot (literally!) to hit the master breaker, incredibly she kept jerking the robot as he held on for dear life. He did manage to hit the breaker and disable the robot, so then she lauged, got up, and left. WHAT!!?? So now all OCCAM 2 is is a paper wieght, and she thought this was funny? Have any of the rest of you had FIRSTer/nonFIRSTer problems like this? How do you deal with them? This was last year, by the way, so cluebats are not a solution. I ask because we're trying to get better PR within the school, and this clearly didn't work, so we'd like to avoid any other minefields.

Arkorobotics
12-06-2005, 09:34 PM
Simple solution, never give a nonFIRSTER complete control of a robot.. I have seen injuries from this concept.

Tristan Lall
12-06-2005, 09:49 PM
In 2003, a reporter from CTV got her hands on the controls for a live Blizzard 4 at the GTR. Unfortunately, she neglected to account for two things: that robot was fast as hell, and the tether was only 6' long. It pulled the tether connector off of the RC, and we ended up borrowing a control system from IFI....

greencactus3
12-06-2005, 09:52 PM
or use software or mechanical means to limit output. if you used the drill tranny simpling putting it into 1st gear is one way. use the clutch... dont let them rip it to shreds... ALWAYS have a remote safety disable switch. easiest way i can think of is have oi ac adapter ready to get pulled from the wall.

Elgin Clock
12-06-2005, 10:14 PM
I know the first instinct would be to hit the breaker on the robot, which I have had to do during a demo as well...

But wouldn't the first thing to do if something like this happened be to unplug the Control system?? Wouldn't that do the same thing as shutting off the master power breaker and be much safer?

Obviously would still you want someone/something (fence) around to make sure people stay away from the robot when it is in operation.

Madison
12-06-2005, 10:20 PM
This is easy.

First, you can respect the girl a bit more by leaving out, "she was a cheerleader," the next time you tell the story. It's irrelevant and sexist.

Second, you can invite her to join the team. You can keep her from breaking things in the future by teaching her how they work.

Third, you can work with her to build a robot that doesn't break when the next "cheerleader" comes along and takes it for a spin.

greencactus3
12-06-2005, 10:21 PM
I know the first instinct would be to hit the breaker on the robot, which I have had to do during a demo as well...

But wouldn't the first thing to do if something like this happened be to unplug the Control system?? Wouldn't that do the same thing as shutting off the master power breaker and be much safer?

Obviously would still you want someone/something (fence) around to make sure people stay away from the robot when it is in operation.
well just one thing that could go wrong. the victors arent calibrated and once the RC loses signal the motors go crazy= robot goes crazy= you hoping the battery runs low SOON. actually im not sure if thats the victors or what, but it has happened before...

Kims Robot
12-06-2005, 10:23 PM
One thought... non-FIRSTer's dont realize how delicate these big hunks of machinery actually are. They are used to RC cars that can be run into walls, driven over sanddunes, and played with by 2-year-olds. So the concept of a big hunk of metal that you put your SOUL into for 6 weeks, but that isnt shock & vibe proof, hasnt crossed their minds!! Be wary!

Two "sorta" similar stories.

1. (my favorite): As I mention in this Essay (http://www.chiefdelphi.com/forums/showthread.php?t=31680&highlight=college+essay) while I was still in HS, we were rushing around putting the robot back together before a match at championships, and before the days of the great amphenol battery connectors *gasp* (yes there was such a day!) one of our mechanical engineers threw the battery in, and wired it up backwards!! Luckily FIRST was smart enough to make us install master fuses back then, and we just blew that. But its why mechanical engineers should stick to mechanical things (and electrical engineers to electrical things!!)

2. An opposing story to what you wrote above... we gave two rookie teams robots for the Ruckus off season event, both drove the robots only once before that day... and BOTH made it into alliances opposing eachother in the finals!! Amazing job for not-yet-FIRSTers :)

greencactus3
12-06-2005, 10:28 PM
well non FIRSTer is a bad term. non robotics associated person would be better. ive done FIRST once, and the rest of my team has never done FIRST yet. but i would trust many with anything ive put my everything into for 6 weeks. OCCRA... ahh. good times.. :p

sanddrag
12-06-2005, 10:29 PM
Third, you can work with her to build a robot that doesn't break when the next "cheerleader" comes along and takes it for a spin.I like this option. From some previous post I made "If you don't like contact, your robot is not built well enough." If you can't put your robot in the hands of someone who hasn't driven it before, without having fear of breaking it, I'd say it isn't built well enough.

Also, a disable switch is always a great idea. (or even pulling the power from the OI)

Jeff Rodriguez
12-06-2005, 10:38 PM
In 2003... It pulled the tether connector off of the RC...

That's why you never screw in the tether. A quick yank and it can come out.

Tristan Lall
12-06-2005, 11:12 PM
That's why you never screw in the tether. A quick yank and it can come out.Believe me, that's been impressed upon everybody, ever since.

Denman
12-07-2005, 06:15 AM
well, this year there is an easy solution. Make a custom port for the competition feed. it uses a standard port and 759 mounted a couple of switches and wired it into the port (don't ask me how, i don't have a clue ) and you can just emulate the pressure pad with a switch
or you can hit the robot reset on the oi and run whilst its resetting itself

kio_chan176
12-07-2005, 10:00 AM
Team 25 just made a game using a simple robot arm. It had no base so you couldn't drive it and the arm was only able to move very, very slowly. There was a hook at the end, which could pose a potential danger, but we made sure no one was anywhere near our arm. The goal of the game was stack mini tetras on various goals. :D This game was displayed at Brunswick Eruption 4.0.

JUST IN CASE anything went wrong, we had a switch close and ready for safety's sake.

sciencenerd
12-07-2005, 10:29 AM
well, this year there is an easy solution. Make a custom port for the competition feed. it uses a standard port and 759 mounted a couple of switches and wired it into the port (don't ask me how, i don't have a clue ) and you can just emulate the pressure pad with a switch
or you can hit the robot reset on the oi and run whilst its resetting itself

Team 1318 made a box that did that in 2004, and used it again in 2005. It is a small grey box you just plug into one of the ports, with a switch for disable and a switch for autonomous mounted in it. Whenever, wherever and whoever is driving the robot, no matter how much (or how little) experience they had, we made sure to always have someone manning that switch with their finger over the disable button, just in case something went wrong.

That allows us to feel more safe with letting people not on the team drive the robot at promotions and things (although we always make sure that they have plenty of space, and always have someone there to advise them when they're doing something wrong).

We have only run into a problem with this setup one time. We were practicing with our robot in the hallways of our school once (they are open air and quite large, nearly as wide as the 2005 field if I remember it correctly). It was after the season, and we were trying to get some members of the team who hadn't been drivers to learn how to control the robot. Somehow, one member of our team got the robot shooting full speed towards a wall. Realizing his mistake, he quickly tried to pull back on the joystick and stop the robot, which probably would have worked. However, the person with the disable switch had seen the problem too and instinctively shut down the robot, so there was no way to slow it down! Luckily all that happened was that we got a little scuff mark on the corner of our chassis (our school's walls are painted concrete, you couldn't even notice the scratch on them).

The moral of this story: Only use the disable switch if the thing you want to stop hasn't started yet, or the driver tells you to. Sometimes it is easier for a (trained) driver to correct a problem than for you to just freeze it.

Edit: changed a few erroneous facts about our box - whoops

Adam Y.
12-07-2005, 10:46 AM
One thought... non-FIRSTer's dont realize how delicate these big hunks of machinery actually are. They are used to RC cars that can be run into walls, driven over sanddunes, and played with by 2-year-olds. So the concept of a big hunk of metal that you put your SOUL into for 6 weeks, but that isnt shock & vibe proof, hasnt crossed their minds!! Be wary!
Im sorry but if you didn't build your robot to withstand being run into walls, driven over sandunes, and be played with by a two year old you didn't do your job. I have seen robots run into walls, drive over large obstacles, fall over, and watched them be dropped five feet off the ground but yet they still worked.

dlavery
12-07-2005, 11:14 AM
There is a very simple answer to this problem: VEX.

Over the summer, Team 116 built a VEX demonstration field (a very simple 8'x8' table covered with neoprene floor pads) and a set of VEX "squarebot" robots. We created a very simple 2-minute game that takes 15 seconds to describe, and then turn over the controls of the VEX robots to anyone that wants to drive. We have had drivers as young as four, and as old as ... well, lets just say they were a lot older than anyone on the team. We have demonstrated it at many public events (the Herndon Festival with over 90,000 visitors, the NBC DigitalEdge Expo with 70,000 visitors, several area school demonstrations, etc.), and well over a thousand different people driving the robots. The relatively low power and mass of the VEX robots (vs. an FRC robot) limits the amount of actual destruction they can do, and we have had absolutely no problems with the public damaging the robots. To the contrary, what we usually have is a reaction like these:
http://www.invisiblerobot.com/robotics/robot_c58a/p1100157.jpghttp://www.invisiblerobot.com/robotics/robot_c58a/p1100161.jpg
We have the team FRC robot to one side - unpowered - where the team members can explain the program, describe the robot, and not let it hurt anyone that does not understand it.

As an aside, I would also point out that our robotics team captain is a cheerleader.

-dave

Cuog
12-07-2005, 01:01 PM
Generally it is good to have a nearly indestructible robot for demonstrations where you let people drive, we have for our demonstratino a person manning the oi power and another person giving the new driver a quick rundown of how to drive,

we have had kids as young as two and three driving one or our FRC robots that was from the year with the boxes(dont remember what year but it was before me)

The only problems with it is that some of the gears have had a tooth or two break off during their long life

artdutra04
12-07-2005, 02:46 PM
There is a very simple answer to this problem: VEX.
Dave beat me to it. You simply cannot beat Vex for public robot demonstrations. If built correctly, the robots are more or less indestructible. Our team recently had a public FIRST demo at our local mall, and we let little kids walking by drive my Space Elevator Vex bot. The elevator and arm were both protected by limit switches, so there wasn't really anything to break.

http://www.team228.org/images/2005/mall/mall11.jpg (http://www.team228.org/index/promotefirst/05/mall.htm)

On the other hand, although driving a FIRST robot may be impressive, it can also be dangerous to bystanders if the robot gets out of control. Also, without a large space, a tetra scoring robot is kind of boring, no matter how cool your operator interface or robot looks. But with the Vex bots, you can get a mini-game going, where people can drive and compete themselves.

This is the key to good public relations for recruiting members to your team - direct interaction. Then they actually see that robotics isn't a boring just-for-geeks club. :) (It worked really well for our team, as almost everyone who was at the first meeting is now still involved with the team. :D )

EricH
12-07-2005, 04:39 PM
Darn, both Dave and Art beat me to this--VEX. We did this for a fundraiser--two Squarebots at a time playing soccer with multiple golf balls to score. Made a 4' by 8' table that we could break into two 4'x4' sections for transport, got a golfer's pool set for the balls and goals, and charged 2 bucks a round, with a quantity discount. No problems other than a couple of people trying to use the sideways motion of the sticks to turn when that couldn't do a ting, but the field wall held. We also had bumper switches to foil Battlebots wannabes from practicing. :)

Wayne C.
12-08-2005, 04:55 PM
I agree with a lot of the above-

First-FIRST robots are OSHA nightmares. If you are letting rookies drive you never just hand over the controls and step back. Somebody always has a hand on a switch ready to kill the machine- perhaps even just unplugging the controller.

Even experienced drivers sometimes do unsafe and stupid things (like leaving the program tether still plugged in to the laptop as the robot flies out in an autonomous mode) : )


Second- If a "cheerleader" can break a robot in one easy swoop then it must not be very durable. Since the season is over why not beef up the frame and bumpers so it can take the hits? Maybe you can patch the damage with her name on it.

Of course there is nothing on any robot the team builds that they can't fix. Look at this as an opportunity to warm up for the new season. ; )


The benefit of getting more kids interested in robots far outweighs a few repairs- even if they are big ones.

WC :cool:

Andrew Blair
12-08-2005, 05:16 PM
A couple things regarding robot damage....1. Not screwing in tethers is a start, but just remember that a serial cable pulled at right angles to it's connector *will* break off. And IFI repairs are pretty pricey.

2. The problem with an FRC robot breaking is not that its not durable, but thats its so big. A good example: go-carts. If you look at a good go-cart, it's pretty well built. However, when I ram my go-cart into a wall, then roll it down a hill, I expect it to be a little worse for wear. Thats why VEX and RC stuff doesn't break; its too light. And most large mechanical devices have pretty high strengths vs. loads. We have weight limits however, and a rolled steel frame is simply not an option. Aluminum is still really, really strong, but it'll have to do.:D

Cory
12-08-2005, 05:55 PM
Im sorry but if you didn't build your robot to withstand being run into walls, driven over sandunes, and be played with by a two year old you didn't do your job. I have seen robots run into walls, drive over large obstacles, fall over, and watched them be dropped five feet off the ground but yet they still worked.

Driving into walls, over sand dunes, falling 5 feet, and having the robot be young child operable are all factors outside the design constraints.

Obviously people don't intentionally make their robots incredibly delicate, but nobody designs their robot with demos in mind, or doing other similar things that the robot was never built for, hence why it's sometimes so easy for them to break (or otherwise cause damage) during these events.

EricH
12-08-2005, 06:55 PM
At one of 330's demos, we allowed team related people to drive (particularly since most of our drive team wasn't there :ahh: ). The thing was that someone who knew the controls was always next to them operating the other function. Plus the crowd was held back, and there was a ditch to go through to get to them, and there were goals all over, so you couldn't do much damage. My mom drove for a few minutes with me on the arm, then we switched, but I was always within easy grab of the disable switch.

As for robot design, design it to last for at least one more competition than you are going to and make it easy to repair, and you should be fine. If you design it to withstand at least two years of competition, you will be fine and have a practice bot for next year.

Adam Y.
12-10-2005, 12:44 PM
Driving into walls, over sand dunes, falling 5 feet, and having the robot be young child operable are all factors outside the design constraints.

What???? Are you telling me that not a single team assumed that their robot could fall from the ground during the 2003 competition if they used the pull up bar. Come on.

EricH
12-10-2005, 12:51 PM
What???? Are you telling me that not a single team assumed that their robot could fall from the ground during the 2003 competition if they used the pull up bar. Come on.
They may not have assumed that they could, but at least one team did. (330 fell off once during LA qualifying rounds with no damage other than being flat on the floor for the rest of the match.) Assume that robots will fall over, be hit by other robots, be hit by game objects, and anything else you like. Build to couteract that. (Oh, and it was 2004. Of course, there was the possibility that a robot could turn turtle on the '03 ramp.)

Cory
12-10-2005, 03:14 PM
What???? Are you telling me that not a single team assumed that their robot could fall from the ground during the 2003 competition if they used the pull up bar. Come on.

If a team used the bar in 2004, then yes, the thought probably occured to them, but if you never were going to hang, or you're using a non 2004 robot, a 5 foot fall was never within the design parameters.

lukevanoort
12-10-2005, 03:55 PM
This was an '02 bot so it was a bit old and had the original (i think) drill trannys in it. We irritated us was not so much that she broke the tranny (most teams have including us) and drove over the wall, but that she kept driving it when our team member was on the robot. In retrospect I don't know why he didn't just yank the OI's power, but at the time I had no experience with the robots or the OIs, so I didn't question the action. If I had thought about it at the time, I still wouldn't have done it for fear of the robot continuing like someone mentioned (ever unplug an N64 controller?).

KarenH
12-10-2005, 06:12 PM
At one of 330's demos, we allowed team related people to drive. ... and there was a ditch to go through ... My mom drove for a few minutes with me on the arm, then we switched, but I was always within easy grab of the disable switch.
Our 2005 robot is VERY easy to drive; I was able to drive it over that little gutter once I figured out the technique. Not like the year our mentors were crashing the robot into folding tables at our sponsor dinner... :D

In my opinion, our scariest demo this year:

The senior pastor of our church wanted us to demo our Championship robot at all four weekend services. The carpeted platform in our church auditorium is about as high as a tabletop, and at the very front of it is a drop off with no railings, much like a theatrical stage. I suggested that the members of the team who were not driving the robot should sit in the front row so that, if anything went wrong, we would be the ones it landed on. The seating didn't actually work out that way.

But, between our excellent drivers and our steady robot, there were no "incidents." And we do not allow novices to drive in this kind of demo.