X-Contamination

From Left to Right: (Blocked by my head is )Galen Bradley, Me [Jeff], Mr. De Soto, (who is partly blocking) Alex Howell, Daniel Susskind, Matt Neber, and Joaquin De Soto. This is from the 2005 Nationals in Orlando, and the robot right there is X-Contamination [Mark 2].

Built in the spring of 2005, X-Contamination [spoken as "Cross Contamination"] was the first battlebot made by RE Robotics. The original intent was to make a Biohazard clone, since we had seen its design perform well against many different battlebot designs. As I have said elsewhere, I was in charge of making the prototype arm (which just so happened to be done in Lego - it was what we had on hand and could be easily scaled to any units we wanted). Due to our intent to make a Biohazard clone, as well as our own inexperience, we were preoccupied with how to make a lifter arm without linear motors. I determined we could just convert the rotational motion of our motors to linear motion using linkages, not unlike the reverse of how a steam-powered locomotive drives its wheels. Later on, I took to thinking of it as more of a backwards crankshaft. This chance occurrence allowed us to make an arm that required no gearing whatsoever to operate. With some additional work, we managed to make the entire set of linkages coming off the motor fit inside the open space of the robot's four bar arm. X-Contamination was completed at 3 AM the night before competition, using an 1/8th inch Masonite baseplate, two Drill motors mounted in 1/2 inch particle board pillow blocks, armor made from 1/16th inch aluminum plate bought from shell lumber, a single 14.4 volt drill battery that snapped into place using the original connector from a drill, and leftover electronics from REbot, an old FIRST robot, including two Victor 883 ESCs, a Spike Relay, an ISAAC 16 receiver/brain, and two high-torque motors.

Its first competition was at the end of March that year, the first annual Regional Battlebots IQ competition (held at the University of Miami). It took home Second Place and Best Engineered that year.

After that competition, we decided to go to the National competition held at the end of April, and proceeded to upgrade X-Contamination. I worked mainly on the Chassis and internal layout, as we switched from the over-sized Masonite baseplate to a two-part chassis. The new chassis was made of two sections of 90 degree 1/16th inch aluminum (again, shell lumber) as a trough for the ISAAC 16 with its new [less glitchy] "battle-board", batteries, and arm, as well a small Masonite baseplate in the rear for the drive & two new Victor 884s (the Masonite was the same weight and strength as the aluminum for overall area, but less prone to flexing under the weight of the robot). It was during this upgrade that Matt Neber (Class of '06) was working on optimizing the arm geometry. At the time, X-Contamination could only lift ten pounds. During testing, he noticed an over-sized washer on one of the arm's drive linkages coming off the motor contacted the front linkage of the arm and pushed it upwards. From this, he designed a cam that would be placed as part of the drive linkages that contacted & drove the front bars for the first few inches of travel, and then the original linkage connected to the rear bars drove the arm the rest of the way. This resulted in a more than 150% increase in the lifting capacity of the arm. In effect, he had made the arm switch from one configuration to another automatically; I am convinced we would have never discovered this with a finely machined robot, as the wiggle-room from hand-made parts are what allows the cam to be the only thing driving the arm for a certain amount of time before the rear linkage kicks in. Also our driver, Joaquin De Soto, along with our programmer, Daniel Susskind, had built a fully-custom controller from the casing of a dead RC car controller. [Joaquin is a pro-level RC car driver, and is ranked pretty high up in the state of Florida] They did this by removing the potentiometers and buttons from at least one IFI joystick and placing them in appropriate places in the car controller, and made sure the original cable from the joystick that connected to the transmitter was appropriately wired. Daniel also created a custom drive-mixing program for the IFI controller, and had previously developed an auto-reset program for the arm.

We finished the robot the day we left for Orlando, and came back with a respectable 4th place.

The following year the Masonite baseplate was replaced with a hand-beaten 1/8th inch diamond plate aluminum, and the weapon motors were replaced with standard car power window motors in time for the Regional competition, where we won First place. Afterward, the ISAAC was replaced with a miniature version of the more standard IFI controllers, that used a standard RC receiver's inputs and could still be programmed. It went to the 2006 Nationals and came back with 5th place, winner of a robot rumble, Best Sportsmanship and Best Engineered for the mini class.

In 2007 the chassis was entirely replaced by a more compact machined 1/16th inch aluminum version. There was no Regional competition that year, and it returned from the '07 Nationals with 5th place and the glory of being one of two robots to beat Executer, as well as being beaten by Executer and being fully repaired with two hours of work and a splash of coffee. Just before the competition I had noted that if the arm was reversed, (pointing out what was at the time the back of the robot instead of the front), it would likely be able to self-right. Unfortunately, there was no time to implement this into that year's design.

In 2008 the robot had its arm reversed and got new lithium battery packs, as well not using any programmed components whatsoever for the first time. Unfortunately, few members took interest in the robot that year so it was otherwise virtually unchanged from when it left from Nationals in 2007. It did not go to Regionals that year, and came out of Nationals with no wins and two losses due to a mysterious electrical glitch.

Currently, X-Contamination is retired and sitting in a box in the room RE Robotics uses for its meetings.

I've intended to finish a "how to" guide for flippers, using X-Contamination's design for a while now, and this is as good a place as any to post it. A somewhat more technical guide will be placed in the 'Design' section in its own thread.

It was only a matter of time before I expected to see this!! lol

Well, the funny thing about X-Contamination was no one ever managed to make a copy of the thing! That, and it's the only flipper of it's design in the entire world history of any combat robotics competition [yes, I've looked pretty thoroughly]. Oh, and it's the true Zombot, returned from the dead to feast on the transistors of the living.

Emissary42 wrote:

Well, the funny thing about X-Contamination was no one ever managed to make a copy of the thing! That, and it's the only flipper of it's design in the entire world history of any combat robotics competition [yes, I've looked pretty thoroughly]. Oh, and it's the true Zombot, returned from the dead to feast on the transistors of the living.

Can someone honestly please tell me if this things dead yet?! lol

It doesn't die. It just lies there sleeping and only wakes when you provoke it, then it attacks, gets killed, and resurrects. But we're not bringing it to San Fran (I don't think, I'm almost positive as a matter of fact), if that's what you meant.

lol no i ment like really dead, the thing has been practicly destroyed and you guys some how get it back together and going, i think i even heard something of coffee being spilled on it
and BTW anytime i see a video of it upside down, i swear the thing looks like a chicken

X-Contamination doesn't sleep; it waits. That said, it should still be quite functional. A bit decrepit though. It needs someone to take interest in it again and do a nice refit.

And yes, our adviser accidentally spilled coffee all over its electronics. It seems like it had no effect though.

Okay, I got the basic history of the thing up. I'll have the arm design guide as soon as I'm able.

Jeff, you look quite sinister in the picture. It is kinda creepy.

haha lolcats moved to lolcats in general discussion.

X-Contamination is now officially dead, as I had to take what was left of it apart to get the measurements for the guide on how to build its weapon.

Jeff L wrote:

X-Contamination is now officially dead, as I had to take what was left of it apart to get the measurements for the guide on how to build its weapon.

Well...it came back to life (kinda) at the Youth Fair. CuddleBunny used it's flipper as a plow/wedge.

heres something ive never understood since ive never gotten that into flippers, why do most of them only use the width of the arm as a flipper instead of the width of the bot like x did

Cody Harris wrote:

heres something ive never understood since ive never gotten that into flippers, why do most of them only use the width of the arm as a flipper instead of the width of the bot like x did

Because they didn't think things through enough, that's why! Really though, I think they want to avoid having the flipper plate being deformed - it's hard to do that to the plate if it's reinforced by the bars of the arm itself.

Sean Rubin wrote:

Jeff L wrote:

X-Contamination is now officially dead, as I had to take what was left of it apart to get the measurements for the guide on how to build its weapon.

Well...it came back to life (kinda) at the Youth Fair. CuddleBunny used it's flipper as a plow/wedge.

But that was a bit more than a month ago, and now I've taken half of the arm apart. Also, since it seems no one is interested in rebuilding it, it's unlikely that robot will ever be put back together again.