Driving control scheme?
 

I am currently debating what type of drive control scheme to use. I am pushing for a system where one joystick controls the two right wheels the other controls the left side. They are pushing for one to control speed and one to control the turning. I just wanted to see what you guys think. We are a rookie team and I am the only one that has ever done first so im trying to convince them that my idea is the best. Any thoughts?

Re: Driving control scheme?
 

Generally, ours had tank drive. Manipulator controls wer generally deployment on one joystick and retraction on the other. One year there were controls in a box in the middle.

To each is their own.

Re: Driving control scheme?
 

unless you are using omni wheels to do tranlational drive then one joystick for the left and one for the right is best it requires the least work and code. THe majority of teams you will see will have this configuration.

Re: Driving control scheme?
 

Tank drive (having one joystick control each side) is the most popular system in FIRST. It's simple, the driver practically doesn't have to think (well, he does, but it's more intuitive.) Having one control speed and the other turning--just use a steering wheel if you can find one that interfaces with the RC; or just use one joystick. The problem with this system is it's very hard to turn fast, unlike two sticks. If you must use an x and y system, use one stick, but two joysticks is preferred.

Re: Driving control scheme?
 

We always used 2 joystick tank drive up until last year, when we switched over to using one joystick for both speed and turning. The 2 joystick tank drive is considerably easier to program, but the one joystick was alot easier for anyone on the team to simply turn the robot on and drive it (I don't know how much easier it was for the experienced competition drivers, but it worked better for just the random member). We will be using one joystick for both again this year.

Re: Driving control scheme?
 

1293 has always used one joystick. I don't know why exactly (probably because we started out with only two joysticks back in the old days).

Re: Driving control scheme?
 

One joystick for left and one for right but those are thumb joysticks on our PS2 controller. :cool:

Re: Driving control scheme?
 

Our team uses tank drive for the most part, but just try both, let your driver(s) play with it, and see what they prefer.

Re: Driving control scheme?
 

We've always been a one joystick team.

I don't get why two are more popular - there is no combination of left and right speeds that a single stick can't produce, and it leaves the other hand free for other things (as well as being more intuitive IMO).

And it's not like it's harder to program - it's in the default code!

Re: Driving control scheme?
 

They didn't do that until last year. But yes, now they give it to us (I think that may have been one of the big reasons we did switch over to it last year...).

Re: Driving control scheme?
 

We have "Halo Drive" (as coined by me for our team). We have the same control scheme as in Halo, left joystick is left, right, forward, and back, while keeping the same heading, and the right joystick controls rotation. And it drives soo heavenly and smooth, a nice change over our overly frictionated (cool word) tank drive from last year. Its the most maneuverable little chassis I've ever personally seen.

Re: Driving control scheme?
 

Team 435 : we have always used one controler, in the begining we had to intergrade the two controles in to one controler which was a pain in setting up the condinate system of the joystick. but now we can spend time on other things b/c the code is given to us for one joystick to control both driving wheels left and right

Re: Driving control scheme?
 

That font is very, very hard to read.


We use tank.. I wouldn't have it any other way.. It is by far the best, as far as I can tell (Try to do this with a single joystick: Go forward, spin around one of the back wheels to 180, and go straight forward) ;)

Re: Driving control scheme?
 

This is interesting. Way more teams voting for two joysticks than one.

The one joystick really isn't that much harder to program. I worked it out on paper in about 15 minutes then typed that straight into the computer. I spent about 30 minutes (that is, 30 minutes of actually working) debugging it when the tracks on the bot kept randomly reversing/ignoring dead bands/spinning the same way.

Our team still has to make some motor linearization code and tweak the code but for the most part it's done.

I think that one joystick is easier to control and leaves the operator's other hand free for a possible second joystick/panel for weapons control. We learned last year that it's best not to have two drivers. That's very hard to coordinate correctly sometimes.

Re: Driving control scheme?
 

I really perfer 2 joystick tankdrive because it gives you absolute control of the robot, you can control either side of you your drivetrain at any speed you want any time you want. However I do think that 1 joystick would be easier for people that havnt ever driven a robot before.

Re: Driving control scheme?
 

We started with both one- and two-joystick options last year. Yes, one joystick was easier for people who had never driven a robot before. However, for those with experience (or after a bit of practice), it was much easier to control using two joysticks.

The issue of turning while going backwards leads to some seriously nonintuitive behavior when using a single joystick. There are fixes, but none seem entirely satisfactory to me.

Re: Driving control scheme?
 

Team 319 is a Tank Drive.. we have used it for a long time... but this year we might try to make a Xbox control work with the system... or a PS2...

Re: Driving control scheme?
 

We've used both in the past. Most of the time, we consult our drivers and see what they would prefer. After all, they are the ones interfacing with the machine most frequently!

We used a pretty unique system last year. We had a 3-wheel swerve drive on our machine, so we couldn't use the standard tank drive. We used a joystick for throttle and a steering wheel for directionality. It seems very complicated to figure out, but it's actually pretty intuitive. I ran the robot in some demonstrations where the students couldn't attend, and it was definitely different, but I would use that control system again. If you try to use a swerve drive with it, make sure you have a good programmer! We actually ran out of space in the RC to be able to do everything we wanted to last year because of the swerve-drive code.

As far as finding a steering wheel goes, I think we brought one in from someone's old collection and modified the connector. It worked just fine.

Re: Driving control scheme?
 

No joysticks!

Thats right, the 492 base driver will not ven be using a joystick this year.

I don't wana spoil the suprise so you will just have to watch the PAC NW regional 1st week.

Re: Driving control scheme?
 

A former student on our team, Daniel Gutmanas, came up with a code for perfect driving using just one joystick (nothing to do with the default code).
You can find all the information here: http://www.avivrobotics.net/tutorials/mixing.pdf

Also visit our team's site : http://www.avivrobotics.net

correction: In the article he wrote team 1557, meaning team 1577# - steampunk robotics (all those sleepless nights programming kinda confused him) :D

Re: Driving control scheme?
 

1 stick or 2...
This is always a hot debate in the FRC. Please see my comments (and those of others) from 2003 in this thread:

one stick or two stick drivv?


Eric

Re: Driving control scheme?
 

Tank drive for the win (hehe)! Some members of our electrical team go in for differential steering (one for speed, one for turning) but us programmers will turn them around. I agree with the poll results. If tank drive were unavailable, one for all and all for one would make sense.

Paul Dennis

Re: Driving control scheme?
 

We split the responsibility of operating the robot between two people, a driver and an operator. The driver controls the robot's placement on the field and the speed of the drive while the operator is responsible for any appendages.I was the driver for my team in the 2005 season. I also drove the robot at the 2004-2005 IRI. I have driven with both single and double joystick controls. Personally, I fell more confident with two joysticks. Many people have said that two joysticks are easier to control for the experienced driver. I suggest that if your team plans on rotating drivers during the season that you use single stick controls. However, if you have enough time during the build season to practice driving, go with a two stick drive.

Re: Driving control scheme?
 

What kind of wheels did you use for this configuration? it sounds very intriguing. but what kind of rotation were you controlling? is that the rotation of the drive train? or the shoulder mechanism?

Re: Driving control scheme?
 

clearly, a dance dance revolution pad is the way to go as to how to control the robot. just kidding :p I don't think FIRST would approve...

seriously though, when I was the base driver last year, our team experimented with both the one stick and the two stick drive.

I prefer the two stick drive because it allows for versatility and it is easy to make small adjustments. Also, the two stick system allows me to rotate on a dime and on the fly. It is easy to maneuver.

Re: Driving control scheme?
 

I recall (My brain's fired from a Bio Test) one year the toggle box with all the controls had two key switches:

1. Changed the direction of the tank drive. Forward was backwards and vice versa to allow quick controls
2. Switched between 1 joystick control for movement and tank drive.

Whether or not they were helped I don't remember but the First switch got a few nods for use that year (Zone Zeal)

Re: Driving control scheme?
 

We were thinking about a neural interface, but decided against it just in case our driver has undiagnosed ADD:

OK, drive forward, turn 20 degrees right....ooh! look at that pretty girl in the stands...LOOK OUT!!!

Re: Driving control scheme?
 

well, the total control of tank drive can be simulated using a good programmer who can give you diagonals and tolerance levels so like if u push foward and then a little to the left, it'll just slightly bend left
~D

Re: Driving control scheme?
 

As far as between tank drive and one stick drive, I find tank drive much easier to use. One thing that I would really like to try is thumbsticks (maybe time to pick up an old analog gamepad...) and have the left stick as the forward and backwards, and the right stick as the left and right.

Re: Driving control scheme?
 

we actually HAVE to use two-joystick drive so that we can program in all the driving "extras" we need for this year's competition. It'd be too hard to program them in with 1 joystick drive. plus our drivers are used to tank drive (drivers are all juniors)....