omni drive vs tank

[BillyGoats]

Originally Posted by SirCharles982

tank treads are WAYYYYY too slow for this game. you gotta go with 4 wheel tank drive. relatively good speed and good push power and easy to do, especially for a rookie team.

do you need me to show you video's? they are not slow so don't say they are.. I will show you video's of how fast and how POWERFULL they are

2004 Mayhem on the Merrimack Fastest Robot Award!

But remember tank treads are slow... Time for you to get your facts straight

Originally Posted by Drew Hopman

Typical answer but not always the truth. You can get high speeds with treads if you have the proper gear ratio. I recall team 61 (i think) moving with great speeds in 04 competition and team 180's old tread system to be very powerful. But be sure to do the engineering before the season starts, or you might run out of time like our team did in 03 and had some serious engineering flaws that we found out on the first day of competition.

We are going 6x6 for this years game....

Yes.. Just look at my signature.. Won a lot of compitions this year..

[Seekthematrix]

tank treads are def not slow, but honestly there is no need for them in this years game. Theres no terrian obstacles other then the 30 degree ramp which shouldnt be a problem to get up. i would go 6 wheel drive and just chain the wheels

[BillyGoats]

Originally Posted by Seekthematrix

tank treads are def not slow, but honestly there is no need for them in this years game. Theres no terrian obstacles other then the 30 degree ramp which shouldnt be a problem to get up. i would go 6 wheel drive and just chain the wheels

defense? yeah that's why you need them to push other robots around from scoring.

[Seekthematrix]

ya you get just as much traction with the pneumatic wheels with those big CIMs it wont be necessary to use tank treads and if any team is smart they will use a pneumatic brakepad system to hold their ground while shooting at the center goal

[Ian Curtis]

I'll bite. This year's game will not be friendly to omni wheel drives (unless you can shoot extremely accurately on the fly). It will also not be friendly to tank treads, although I am not sure that is what you meant. Tank does not mean tank treads you guys. It could mean a skid steer system, which would be good, unless you want to go ramp climbing. Although after last year and 116's incredibly wicked sweet drive, I'm sure you can think of something cool.

[Seekthematrix]

Originally Posted by iCurtis

I'll bite. This year's game will not be friendly to omni wheel drives (unless you can shoot extremely accurately on the fly. It will also not be friendly to tank treads, although I am not sure that is what you meant. Tank does not mean tank treads you guys. It could mean a skid steer system, which would be good, unless you want to go ramp climbing. Although after last year and 116's incredibly wicked sweet drive, I'm sure you can think of something cool.

Im not saying it wont be friendly to tank treads im just saying it wont be neccessary your better off going witha 6 wheel pneumatic tire drive train, that ramp isnt going to be to hard to get on. other then that its all about speed, traction, and movability. A functional holonomic drive train is fast as h*** and nice manevability if you practicle driveing but if u get pushed you got zero traction, we even replaced the wheels and added tire treds we literally glued on with some industrial glue the traction increased but if you get pushed you slide.

[Henry_Mareck]

it is possible for a crab drive or an omni drive to get up the ramp with the help of another robot. There will be plenty of tankbots that can push them ramp, just make those wheel/motor assemblies strong.

[sanddrag]

I think a crab could get up in its own but an omni would need the assistance of a dropdown high traction roller of some sort.

I think a crab is perfect for the game, but I don't think my team wants to go that way.

[Theory6RobotiX]

I'll bite. This year's game will not be friendly to omni wheel drives (unless you can shoot extremely accurately on the fly.

Omni wheel drives, when not being useful while climbing the ramp, will probably prove to be extremely valuable when a team is positioning itself to shoot the balls into the corner goal. Lets say you have positioned your robot in front of the goal to shoot and you find yourself a little too far left. Without Omni wheels its given that u will turn right, go forward a little and turn left again to face the goal. Precious time lost...which wont be if you use an omni drive system.

My team has used a four wheel drive system with doubled up wheels wrapped in tread(from McMaster Carr) and two pneumatically activated castor wheels. If all four wheels are on the floor the robot has a LOT of traction and works well as a defensive robot. If the castors are actuated and pushes the front wheels up, it gives it the manuevarability required in the FIRST games. We have found this to work quite well.

On the topic on tank drives, it is a very hard thing to perfectly execute. Tank drives require a lot of work and the result is not very much advantageous over a normal four wheel drive system.

These are just my thoughts. The game dynamics on the field will also have a great say on the reliability and advantages of each of these different systems.

Good Luck

[Lil' Lavery]

Omni bots will have a place in this year's game, although I dont know if 116 will use a holonomic drive again. More advanced programming teams may like omni-drives to "shoot on the fly", especially if they dont develope a turret system for their launcher. Agility and speed will be essential in reaching the corner goals/HP stations, because you CANNOT power your way to them (youll just jam the opponent into the corner, and its gonna be near impossible to get them out).
It is POSSIBLE to create an active suspension system, although very difficult, for a holonomic or mechanum drive to get up the ramp.

[greencactus3]

if it werent our "first" year doing this we would push for omni or crab drive... and it would be nice if the "shooter" were ALWAYS pointed at the goal. no matter which way the joystick is puished the robot moves int the x/y accordingly but the programming keeps the front faced towards the goal.
i guess a rotating top would do as well

[Sepsis900]

regarding the tank treads- it's not so much that they're slow, it's that they're not good for turning, which will probably end up being an important part of this game.

[Jeremiah Johnson]

Originally Posted by greencactus3

if it werent our "first" year doing this we would push for omni or crab drive... and it would be nice if the "shooter" were ALWAYS pointed at the goal. no matter which way the joystick is puished the robot moves int the x/y accordingly but the programming keeps the front faced towards the goal.
i guess a rotating top would do as well

That was the first thing that I thought of once I saw that green light. Set the camera to home in on the light and rotate the firing mechanism.

I'm pretty sure that team 648 is going with a crab steer system and that is the perfect drive system for that design idea. This will also be our first year for crab but we have been testing design and coding on the Robovation bot.

[ZoNeGuY]

Tank treads would be profitable if you can get the gear ratio adjusted so that its fast enough to keep up. Problem is, the biggest advantage of having treads is their grip and strength on the carpet. So gearing it for speed would lose the power aspect of having treads.

[Mike Norton]

Tank treads would be profitable if you can get the gear ratio adjusted so that its fast enough to keep up. Problem is, the biggest advantage of having treads is their grip and strength on the carpet. So gearing it for speed would lose the power aspect of having treads

If you look at the video you will see how fast we run at. we would be one of the fastest robot on the floor. but with the most power. you are right you have to get the gearing right. we always used 4 motors for the drivetrain.


how fast do you want to go. to fast and you have no control. Now with multi gear shifting we have all we need.