Drivetrain, what did you use?

I just wanted to hear what people used for their drive trains including:
Team #?

of years of participation?

and type of motors?

and type of drive wheels?

and type of non-drive wheels?

Transfer system(chains, belts, etc.)?
Transmission (not including supplied ones)?
Steering?
Sensors?
Success?
Problems?
Next year?

My response:
team 997
2nd year
2 drill motors
2 solid rubber 9"dia. 60 durometer 3" wide
2 wheel chair wheels
direct drive via shafts and gears
the supplied right angle gear box
automotive rear-wheels steering
no sensors
we busted the supplied gear box once and our steering sucked
never use automotive steering ever.
next year simple box chasis tank steering as many motors as possible and a transmission.

Team 696
3rd year team
2 drills and 2 chiaphuas
4 Skyway 9x2 Beadlok turned down to 8.5 di
0 non-drive wheels (casters are not allowed near our robots)
#35 Chain with carbon steel sprockets riding on 5/8 keyway shaft
3.5:1 reduction between Chiss and Drills; 4.8 reduction between drills and wheels
Skid Steering
No sensors
Much success, 9fps and loads of torque.
Problems - Misalignment, shafts wandering out.
Next year - Provided we have the same equipment, we will either do the same thing with some minor refinements or have a totally new 2 speed drive. Depends on game and engineer support.

Team 296
5 years
2 drill, 2 CIM
4 solid rubber 6" wheels
no non-drive wheels
belts between the motors, chains to the wheels
supplied transmission
skid steering
no sensors
success - ~10 fps and lots of power
problems with pulleys coming un-setscrewed and with drill transmission
next year - depending on the game, maybe something a bit more complicated like crab

Team 422
4 years
2 CIMs (previously 2 CIMs and 2 drills)
2 6 inch wide 6 inch diameter machined aluminum wheels with hard neoprene covering
2 HDPE machined skids - 3 inch diameter touching the floor
Direct drive using a gearbox for the CIM to gear it down to the high speed of the drill; we then mated both on a giant 80-tooth gear on a 5/8" shaft to the wheels
Two-wheel drive (tank-style steering)
Two optical sensor encoder wheels to count the revolutions per minute
The giant wheels were great on the ramp, and the CIMs gave us some good pushing power.
Our robot was not symmetrical and the weight was balanced more over the skids, so we had some trouble getting weight issues settled. We eventually ended up placing over 20 pounds of dead steel weight over our drive train.

Next year we’re going to deal with the symmetry issues, but this two-wheel drive was very successful, small, and modular, so I think we’ll keep it.

Team 201
6 years
2 CIMs
4 1.5 inch wide, 6 inch diameter custom machined aluminum wheels
No non- drive wheels
Chain drive from a 2-speed transmission
Skid steering
No sensors
Success- really fast, good amount of power, no reliability issues
Problems- can’t turn in high gear
Next year- not my problem :stuck_out_tongue: I’m a senior, though I hear my team is trying for swerve drive next year… we’ll see…

-Team 639 - Code Red Robotics
-This was 3rd year.
-2x Chiapuas
-2x Modified Skyway from Kit for back
2x Omniwheel with 65 grade urethane
-No non-drive wheels
-Chains
-No Transmission, high torque 6.5fp
-Tank Drive, logarithmic control
-Optical Sensor for bin tracking
-Great success
watch www.orbitreview.com/~temp/639movies/639_d.wmv
-None (each regional we had nothing to fix/tune after practice day because we actually spent the time to do tings right this year. We just left the robot outside in Chesapeake for cooling :slight_smile:
-… very secret

Team 6
9? maybe 10?
2 drills, 2 CIMs
4" brecoflex pulleys
0
Brecoflex belts (the green)
None
Sort of
None
A LOT of speed. We were one of the fastest at UCF.
We couldn’t really turn until Sat. after we broke the belts in a little
Depends on the game

Team #1018
First Year
2 drill motors
2 pneumatic tires from a hand cart
2 UHMW skids
#35 Chains
Sprokets from MSC with about a 2:1 ratio
Tank Drive
No Sensors
Nice mix of torque and speed
In Chicago we had problems with the chains walking of and in one case had a connector link fall off
I think we are going to try to make a gearbox this summer

Team 481
4th year
2 Drill, 2CIM
4 Rubber skyway wheels 9" dia
0 non- drive
Gears for cim, provided gearbox for drills
0 sensors
Succesful…kinda - drill trans kept breaking, cim gear box sheared teeth and broke shaft, but no problems at nationals
Next year…shifter

*Originally posted by maclaren ***
Team #?

of years of participation?

and type of motors?

and type of drive wheels?

and type of non-drive wheels?

Transfer system(chains, belts, etc.)?
Transmission (not including supplied ones)?
Steering?
Sensors?
Success?
Problems?
Next year?**

-Team 188, Woburn Robotics.
-6 years of participation.
-2x CIM, 2x Drill, and 2x Fisher-Price.
-Wooden wheels with tread, four-wheel drive.
-No non-drive wheels.
-Chains run to front and back wheels for four-wheel drive.
-One-speed only.
-Tank-style steering.
-Sensors on the wheels to count revolutions and/or pointing down to detects the line or the HDPE.
-A good balance between speed and power; in a fairly high gear (speed of about 9ft/s), we could still push well because of six-motor drive, with a low-friction simplistic gearbox
-It draws way too much power, and by the end of a heated match, our robot can barely move. So many drive motors sometimes cause us to trip breakers. We made the mistake of using small chain rated for about 1000 pounds (25), instead of something stronger, we went through 13 of them because they stretched and snapped all the time. Our treads kept delaminating from the pushing matches we got into, so a better means of traction needs to be developed.
-Next year, we’re going more complex, possibly with a new gearbox design conceived on the plane back from Houston that can do speed and power without most of the drawbacks we faced, and that’s all I’ll say. We’re looking at tank treads also. Anything else is just speculation, stuff I don’t know, or stuff I don’t want everybody to know. :slight_smile:

Team 25
7 years participation (2 under my belt)
2 drills, 2 Chippys
3 wheels a side.
0 nondrive wheels
Direct drive (all gears baby!)
1 speed
Tank steering
No Sensors
Success- 13.6 fps, 3.2-3.6 autonomous time.

Problems- Drills! ARGH! Drove us crazy at first. Our programmer and pit crew came through in a miracle to fix that one.

Next year? Who knows.

*Originally posted by maclaren *
**I just wanted to hear what people used for their drive trains including:
Team #?

of years of participation?

and type of motors?

and type of drive wheels?

and type of non-drive wheels?

Transfer system(chains, belts, etc.)?
Transmission (not including supplied ones)?
Steering?
Sensors?
Success?
Problems?
Next year?
**

  • 1072 (go hrt!!! :D)
  • rookie team
  • 2x Drills
  • 4x skyway wheels with traction material epoxied on (back wheels were effective on the carpet/ramp, front wheels were effective on the HDPE)
  • no non-drive wheels
  • chain drive for both front and back, motors mounted vertically using helical gear set
  • bosch transmission and supplied helical gear sets
  • tank-steering. the bot would skid on the wheels not suited for the material it was on (if it was on the ramp/carpet, the front would skid, if it was on the hdpe, the back would skid)
  • 3 banner sensors mounted on bottom for line-following, though we didn’t end up following the line
  • the drivetrain worked pretty well. *]The traction material fell off the wheels alot, and we had some wiring issues with the motors. our transmission broke once, but it was easy to fix. our servo-powered gearshifters never made it onto the bot. there wasn’t enough torque to move the little switch on the bosch transmission.
  • don’t know about next year. We stayed away from more advanced systems like omniwheels and crab drives cause we were a rookie team, but we might just be more ambitious next year :wink:

Team 294
Seven Years
2 Drill motors
2 9 inch skyways
2 non drive wheels (locked casters)
First gearboxes
None (we stay in low gear)
2 wheel steering
None for drive
SoCal regional finalists (we lost one match)
We didn’t lock the casters at first, causing problems going up the ramp and popping breakers at Phoenix
Next year we are planning something like 111s drive, that was our plan A (ended up with D)

Team 212
5 of years of participation
2 drills
8 inch pneumatich wheelchair wheels
No non drive wheels
Chains
Gearing off of the FIRST gearbox
Tank style, we had a very short wheelbase so we turned really well and had the 4 wheels on the ground for the grip
No sensors
Never had any problems with the drive train, we made this thing like a car with hubs and all it was 1000% sucessful
Next year? i dont know depends on the game duh!

Team 461 - Westside Boiler Invasion
4 Years
2 Drill Motors
4 Skyway wheels. Modified and lathed down an inch or so with supergrip rivited into a channel in the wheel for better traction.
None
Chain. 1.5:1 Gear ratio
None
Tank
Rotary Encoders on the front wheels
Speedy, Robust, Easier to fix and replace stuff then our previous attempts at a drive, we just decided to go simple and not mess with complicated stuff.
We didn’t have alot of torque.
We are going to dive into the wonderful world of transmissions:)

Team 824

Second year team

We attempted to manufacture our own gearbox. Shifter was taken off to make manufacturing schedule. All parts were student made - reliablity was good with 1 motor, but under 2 motor loads, reliabilty was a problem. (it exploded on the field at our very last match at PNW).

  • Tank drive robot
  • 2 “drive pods” modular drive system, on and off the robot very quickly.
  • Optical encoders on driven wheel.
  • Custom made aluminum wheels - attach just like a car’s wheel with a wheel flange. Started out as a track system but the tracks kept falling off.
  • Each pod contain 1 chip, 1 drill motor. There is a matching stage where the free spin RPMs are matched, then the output of that goes through the drill reduction box. Custom outtake shaft then drives the wheels.

Problems we encountered:

  • Failure to account for the side load on the helical gear
  • Bad construction quality on some of the press fits.
  • Failure to calculate in the backlash - I used theoratical spacing for all the gears - that was a BAD mistake.
  • Lack of tools and trained personnel (no one could weld, didn’t have a knurling tool for press fits, no CNC trained operator to cut the bearing pockets, etc.

-=- Terence

Drivetrain, what did you use? (post #1)

I just wanted to hear what people used for their drive trains including:

Team 980
2nd year
Motors? 2 CIMs
Drive wheels? 8 wheels, 4 at a time.

and type of non-drive wheels? 4 wheels on the ground at a time, and the other 4 spinning in the air

Transfer system(chains, belts, etc.)? Gear boxes and chains
Transmission (not including supplied ones)? 2 Custom Gear boxes. 8 full time spinning wheels. We used pneumatics to push a lever which rotated 4 large wheels down for high gear and 4 small ones for low gear.
Steering? Tank
Sensors? Gyro for autonomous movement, potentiometers for controlling the position of 3 arms.
Success? We have a 13 foot telescoping arm which was exceptional at taking down the stack from our starting position.
Problems? We had 3 arms, one 13 footer, and 2 for pushing and stacking bins. That left us short on weight for our drive system. In making everything light enough, the drive system was too flexible and we lost chains if pushed sideways. Later we found ways to reinforce it.
Problem 2: In 3 competitions, we tipped a total of 3 times (average of 1 per competition) when rammed by other robots.
Problem 3: After watching other robots in Houston, our acceleration could have been better. 4 motors would have helped. Also in high gear, our wheel base was short which made us rocky given our high center of gravity.
Next year? I would like 4 motors in the drive train, hopefully with shifting.

-Team 341
-My second year, team’s fourth
-2 drill motors
-4 drive wheels
-0 non-drive wheels
-Chain drive
-We welded ourselves into low gear :wink:
-Tank steer
-Sensors: gyro for autonomous position control, optical sensors to pick up top of the ramp.
-Success: +100% autonomous mode; +GREAT wheels (high traction); good tradeoff of speed and torque
-Problems: -Drill motor mounts; -Wish we were a little faster
-Next year: Expect 4 dedicated drive motors, almost certainly

Team 254 (Cheesy Poofs)

of years of participation? 5 years

and type of motors? 2 drills this year

and type of drive wheels? 4 6"X1" custom wheels with blue tread material (forgot where from)

and type of non-drive wheels? caster dropped down with a pneumatic cylinder only for autonomous steering

Transfer system(chains, belts, etc.)? serpintine chain
Transmission (not including supplied ones)? none other than supplied drill transmissions, which we shifted with servos
Steering? during autonomous we dropped down an angled caster
Sensors? none
Success? yes! no breakdowns at Nats, we drove well, getting to the boxes in 3.8 s in auton, but by shifting could still outpush most robots
Problems?, a few problems with the transmissions at SVR
Next year? gears not chain (we broke a master link in a match at SVR and chain is a pain)

Team 812
2 years
2 Drill Motors
4- 9 x 2 skyways
No No No non-drive wheels
Chains that control the sides of the robot
Supplied Transmission with a few adjustments nothing to gears

Steering: 2 globe with Universal Joints to articulate wheels
3 types of steering-
Mode A: Where the rear and front turn in opposite directions like Chevy’s truck commercial
Mode B: Where the rear and front steer same direction
Mode C: Tank

No sensors
Success: 6th at AZ 9th qualifying

Problems: Not that good because the wheels could only turn 30 deg, we had 10 deg of play to the left, design problem with the key always shearing under the globes DO NOT USE THE HOUSING FOR THE TRANSMISSION GIVEN, We had every possible problem happen to us at least 3 times at SoCal.

DONT USE TOO MANY CUSTOM PARTS, THEY"RE A REAL HASSLE AT COMPETITION ESPECIALLY IF THEY BReAK BETWEEN MATCHES

The team was planning on using chiaphua’s with high reduction, the mechanics team and I wanna do and plan this summer a dual output, shifting on the fly with at least 4 gear ratios drive system.

Or maybe Servo?