Welcome to Team KISS Tips
Team Kiss was founded in 1998 by Steven and Lowell Nelson.
for the purpose of building and fighting combat robots and world domination of the sport.
Over the years we have had our ups and downs, but we have always continued to try and improve our machines and continue learning more every day.

Steven Nelson was the Technical Manager of the RobotClub and Grill in
No. Huntingdon Pennsylvania.
We provided the worlds only permanent robot fighting facility and restaurant.

That facility is now closed but the knowledge learned there lives on.

Evelyn (A modified Dawg) Heavyweight champion.
Yes Pushybots Do Rule.....

Team K.I.S.S had a good year in 2003.
(4) 220 Lb Heavyweight Championships. (Evelyn)
(1) 1 Lb Antweight Championship (Snack Break)

Where to buy robot parts .

Ant weight parts.
sozbots.com
Sozbot is short for sixteen oz. fighting robots they provide parts for Ant and Beetle weight robots they offer custom Sozbots speed controllers, drive motors, wheels, miniature receivers and lots of other cool parts to help you build a nasty Ant or Beetle weight robot.
(I know I've fought some of them).
robotcombat.com
Jim Sementowski (Team Nightmare) runs this online store he carry's part for Ants and Beetle weight robots as well as parts fort all of the weight classes up to the Super heavy. This is a great place to get started on your journey for world conquest in robotic combat. After touring his online store be sure to check out the rest of his huge web site. His links section will take you to most all of the robotic combat team web sites on the planet where you can find tips on how to build a killer machine from the people who build them.

Servo City
Servo city supply's a large variety of servos, radio systems, speed controls chains, sprockets and gear reductions. They are also a dealer for both Futaba and Hitec radio transmitter and receiver products. If your building an Ant or Beetle you want to check out these guys.

Tower Hobbies
Tower Hobbies is one of the largest hobby parts company's around many of the parts they sell are just the ticket for your robot building needs in all weight classes. Spend some time here and order their catalog it will become your wish book for many of your robotic projects.

Major Hobby
One of the places that Team KISS has found good deals on radio systems. A good company that offer great service. Check them out.

Modifying aircraft radios 72 Mhz. to ground frequencies 75 Mhz.
Most of the time it is not possible to buy a radio transmitter/receiver with more than 4 channels in the 75 Mhz band. fortunately there a fellow named George Steiner at GSP products that will re-tune your receiver or transmitter for you and he does a great job. He provides quick turn around time usually two or three days days. George does not have a web page but you can call him at (916) 362-1962. He is located in Sacramento California. Make sure you call him BEFORE you make your radio purchase so he can tell you if your radio is retunable.

Builder Quick Guide
Before building a robot you have to make a few choices.
1. What weight class will I build for?
2. What weapon type will I be using?
3. What type of drive train will I use?
Will it be a walker a shuffler or tracked or wheeled?
4. How fast will I want the robot to go?
(10 mph is a good target speed but some build machines capable of up to 30 mph).
5. What diameter tires will I be using?

To convert in-lbs to oz-in multiply by 16.

1 ft-lb = 12 in-lbs = 192 oz-in.

So to get motor torque in ft/lbs divide motor oz/in rating by 192.

Building the drive train
It is commonly accepted that a competitive wheeled pusher robot drive train will have (at least 1 Hp). per 50 lbs of robot weight.
Consider this when choosing motors.
Personally I like to build drive trains with a lot of torque available to my drive axles; my goal is to try and produce 1 ft lb of torque for every lb of robot weight.
My goal is to never stall my motors so I build a drive train capable of smoking the tires.
Fortunately with the motors available today this is getting easier to do.
Example 340 lb robot.
2 Drive motors (1 per side)
3" Mag motor 4.5 H.P 19.375 ft lbs of torque at stall. 4900 rpm at 24vdc.
Total combined  H.P (9) with two motors
4WD drive train platform.
Tire diameter 10.5 inch. 410 x 350 mm go-cart tires
Target robot speed about 12 mph.
Target total torque at drive axles 340 ft lbs
So if I take a 3 " Mag motor with 19.375 ft lbs of torque and use a 12 to 1 gear reduction the motor will produce 232.5 ft lbs of torque at the drive axle.
19.375 ft lbs of torque x 12 to 1 reduction = 232.5 ft lbs of torque per side

By using a motor for each side of the drive train my combined torque will be 465 ft lbs. (Oh ya that should work).

Formula for calculating tractive force.
To calculate the robots tractive force we need to know a few things.
1. Robots weight
2. Tires coefficient of friction
(.9 is about as good as it gets) you will probably get less.
3. Total drive train torque at the axles in Ft Lbs.
4. Tire radius converted to feet.
Example:
Robot weight 340 lbs
Tire coefficient of friction .9
Total drive train torque in ft lbs at stall 465
Adjusted tire radius = tire diameter 10.5 inches /2/12= 0.438 feet.
 So this gives me 340 lbs x tire coefficient of friction .9 = 306 lbs down force.
Adjusted tire radius = 5.25/12=0.438 feet
465 ft lbs of torque / adjusted tire radius in feet =1061 lbs of  tractive force.

That's about 3.46 times what I need to move the robot. Sounds good: the tires will smoke way before the motors stall. Even with the weight of another robot on mine, I have a nice safety margin.

In response to a post on a forum I've added some examples on using this math for comparing gear reductions and drive train power outputs.
OK now we can look at the Data

Heavyweight Robot 220 lbs

10" diameter tire

Target speed 10-12 MPH

NPC motor  part #4200 Aka Scott Motor (Good choice)

Scott motor specs at 24 VDC

max. speed 3350 RPM

Horsepower rating 3.8

Stall torque 281 Inch lbs / 12 = 23.416 Ft lbs (I think in Ft. lbs)

Stall Current Draw 470 Amps

OK lets plug some numbers.

Maximum coefficient of friction with good tires and a good surface .9

220 * .9 = 198 lbs on the ground applying traction

Once I now the tire size I find its adjusted tire radius in feet (ATR)

Tire diameter / 2 (radius) /12 = (radius in feet)

10 inch tire / 2 = 5 / 12 = 0.4166 feet <---adjusted tire radius in feet. (ATR)

Now we need to make some torque with this motor.

 (I like a lot of torque at my axles)

At Stall the NPC 4200 (Scott motor) produces 23.416 ft lbs of torque. (Nice)

Lets shoot for about 200 ft lbs of torque.

We make torque with gear reductions (more reduction = more torque)

Divide motor shaft speed by the total gear reduction ratio for axle speed.

Multiply motor stall torque in Ft. lbs by the gear reduction for axle torque in Ft. lbs.

By the way, The term (A lower gear ratio) refers to a lower final output shaft speed. Example a 10 to 1 reduction is a lower ratio than a 9 to 1 reduction.

9-1 Axle speed 372 RPM's axle torque at stall 210.74 ft lbs

9.5-1 Axle speed 352 RPM's axle torque at stall 222.45 ft lbs

10-1 Axle speed 335 RPM's axle torque at stall 234.16 ft lbs

10.5-1 Axle speed 319 RPM's axle torque at stall 245.87 ft lbs

Hmm the stall torque for these ratios look pretty good.

OK now we can look at the Data

Lets check our power or tractive force using these gear reductions.

9-1 Axle speed 372 RPM's axle torque at stall 210.74 ft lbs

210.74 ft lbs / ATR 0.4166 = 505.86 lbs tractive force

9.5-1 Axle speed 352 RPM's axle torque at stall 222.45 ft lbs

222.45 ft lbs / ATR 0.4166 = 533.96 lbs tractive force

10-1 Axle speed 335 RPM's axle torque at stall 234.16 ft lbs

234.16 ft lbs / ATR 0.4166 = 562.07 lbs tractive force.

10.5-1 Axle speed 319 RPM's axle torque at stall 245.87 ft lbs

245.87 ft lbs / ATR 0.4166 = 590.182 lbs tractive force.

OK now we know we can make a lot of power with these motors.

How fast will the robot go?

Calculating the robots speed is really easy

Measure the tire diameter in inches from a flat surface to the top of the tread

Multiply the tire diameter with the axle shaft RPM and divide by 336.

So we are using a 10 inch diameter tire.

9-1 reduction gives 372 axle RPMs times a 10 inch tire divided by 336 = 11.07 MPH

9.5- 1 reduction gives 352 axle RPMs times a 10 inch tire divided by 336 = 10.48 MPH

10-1 reduction gives 335 axle RPMs times a 10 inch tire divided by 336 = 9.97 MPH

10.5-1 reduction gives 319 axle RPMs times a 10 inch tire divided by 336 = 9.49 MPH

Now after all of this fun we have several choices of gear reductions to ponder.

Since my target speed was around 10-12 MPH a 9.5 reduction with a 10 inch diameter tire will get me pretty close to my target speed at 10.48 MPH. My tractive force per side at the axles will be 533.96 lbs the total will be this times two or 1067.92 lbs tractive force.

Gee' this sounds like a number I might use for a pushybot.

If I figure that my down force or available traction on a 220 lb robot is the robots weight times its maximum coefficient of friction .9 is 198 lbs.

I can divide the total tractive force by the traction available to see what it will take to smoke the tires.

Lets try it...

Tractive force 1067.92 lbs / 198.0 lbs = 5.39 times the torque I need.

At this point I do a rough guess and divide the motors stall torque by this number the Scott motor can draw up to 470 amps at stall at 24 VDC.

So 470 / 5.39 = 87.1 amps to smoke the tires. This would be with maximum traction most arenas don't have this much traction.
But on  clean dry asphalt with rubber tires you might get this much.

With this gear ratio and these tires I would be thinking I need a speed controller capable of at least 200 amps. Its always a good idea to have a larger controller than your expected current draw.

Oh and 4WD is a must, you can't hold this much torque with 2WD easily.

This is how I do it any ways.

By the way the Scott motors are very cool and if geared correctly very reliable. The only downside is they are heavy at 15.7 lbs.

Twackbot from Heck

Speed controllers. You have several choices of controllers.

Vantec the RDFR 38E to the RDFR 47E.
These are dual motor controllers
Rated up to 220 amps (briefly)
Very good controllers
Usually produces white smoke when they fail.

Innovation first. Victor 885 controller.
You will need two of these one for each motor
Rated at 120 amps continuous
Can handle up to 300 amps for about 1 second
Very good controller.
Can produce red to violet smoke when they fail. Very pretty.

Robot Power speed controls(OSMC)
These controllers came from a open source of information provided by builders.
Robot Power sells several versions of them.
They have been proven and refined by combat and severe testing.
OSMC/MOB 14-50 VDC: 160 amps continious-400 amp surge.
OSMC/uMOB14-50 VDC: 160 amps continious-400 amp surge.
MC1/MOB 14-60 VDC: 400 amps continious-700 amp surge.
Very good controller
They produce a interesting mix of yellow to green smoke when they fail.
Which isn't often..

Robot Solutions speed controls (OSMC)
Robot Solutions was involved in the original design work on the OSMC controller and now produces several improved versions. They offer such cool features as current limiting and lots of mixing functions.

MC1-HV  4- 45 VDC 400 amps (Pretty Beefy stuff here).
uRRC1.0 Micro MOB  (Radio interface)
uMOB2 (allows for radio mixing single and duel stick).
RS80D Duel motor 80 amp speed controller.
RS80D/MC1-HV Combo
(Provides a Duel motor controller and a serious weapon control system).
Very good controllers.

4QD-150-24/36 or -48 VDC: 160 amps cold
4QD-200-24/36 or -48 VDC: 210 amps cold
4QD-300-24/36 or -48 VDC: 320 amps cold

You will need two of these one for each motor.
You will also need a radio interface.
Very good controller
Sorta large in size but their pretty tough.

Usually produces white smoke when they fail.

RoboteQ
This is a dual motor controller
AX2550 12-40 VDC: 120 amps continuous.
Current limited.
Computer compatible through serial port.
Has a analog feedback mode that reads a variable resistor.
You can make a Big Dawg servo with this controller.

As you can see no one makes a controller that can handle the stall current of many of the more powerful motors we use in robotic combat.
(For  long periods of time).
. This is the main reason that you need to gear you motors so they never even come close to stalling and drawing their maximum currents.

It is also possible to use Nicad or Nimh battery power.
For the best batteries (I know of) you really need to talk to Steve Hill at

Robotic Power Solutions.

These guys offer the best battery technology available.
Battlepacks are as good as it gets in portable power for your robot.
Make sure you talk to Steve Hill before demanding high current draws from his Battlepacks.
He will tell you what you will need to get the job done and Win.

I would like to thank Michael Mauldin (Fuzzy) for helping me with the ATR math.

It was the key to calculating everything and has saved me lots of money from just guessing on what parts to use.

Recently I watched the Robo-One machines in action. They are just Too cool.

 Robo1 Page1
Robo1 page2
Robo1 fights
Robo1 fights page1
Robo1 fights page2
Robo-one videos

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Construction pictures of K.I.S.S
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