Smoke, sparks, and fractured steel!

My 25 kg (55 lb) combat robot, Endotherm, participated in the first ever BattleBots in Long Beach, CA.

Summary for Endotherm
Opponent Win/Loss
Defiant Loss
Missing Link WIN
Spike of Doom WIN
Sallad Loss

Arrival at Long Beach

After going through the turmoils of attempting to fly with a robot, tools, and gel-cell batteries (Don't pack them, most carriers require them to be packed in a special seperate package.), I arrived at the Motel 6 on Westminster Ave. in Westminster, a short drive from the Pyramid. My father and I started right away for the finishing touchs of the robot: paint, mounting, and padding. I hadn't mounted the receiver, antenna, or speed controllers, and I needed to add the padding for the batteries, so I started on that.

First off I had to put Anderson Powerpole connectors on one of my two spare Tekin Titans, as I blew one in testing before I left. As I was testing it out, however, something shorted out, and my hotel room began to fill with acrid smoke of insulation buring off. Looks like my spare controller was bad! In the process it also completely destroyed my wiring harness.

After a minute or two of choice four-letter words, I pulled out my last spare Titan. After converting the connectors, I tested it out using my test power harness, and things looked well. At this point, however, I was fed up with working on the electrical system, so I worked on the battery padding and electronics mounting. A few hours of this, and I was tired and ready to sleep. The rest, I told myself, I would finish in the pits before the inspection/weigh-in.

Weigh-in and Safety Inspection

We arrived at the Pyramid at about 9:30 AM, checked in, got our badges, carried our equipment to the table, and I started on the wiring harness. After about one hour, the harness was done, and it worked flawlessly. The master power switch worked fine, as did loss of RF signal. One thing that became a pain was the fact that I didn't want to risk using the battery-replacer circuit in the Titans to replace the seperate receiver battery, and as such I kept having to disconnect the receiver battery from the receiver between matches. The placement of the receiver and battery made it difficult to connect it back in, and often I had to remove the bottom armor in order to connect it. Obviously, this was a small error in my part.

Next, I took the robot to weigh in, where the scale read 48 pounds--seven pounds under weight. As I planned to have a saw weapon on the front (and never got around to it), the rest of the robot was right on the mark. Endotherm passed the safety inspection after I corrected a problem with one of the servo-wire extenders that came loose. Endotherm was now ready to rock and roll. I put the batteries on charge, my father sharpened the front spikes some more, and the rest of the day was spent checking out the competition.

Saturday Morning Session

We arrived at 8 AM on Saturday, anxious to get underway. I was worried as to the effectiveness of the last-minute spikes, but it was too late to worry. I anxiously awaited a glimse of the brackets, and after some persistance (and peering over shoulders), I finally saw our first opponent:


After another bout of choice four-letter words for being seeded to fight the reigning RW champ in the 50 lb class, I decided to look at Endotherm for weaknesses. Defiant's weapon was a four-bar flipping arm a la Biohazard, and it was fast and effective. Since Endotherm was designed to run upside down, I knew that as long as I stayed away from the edge of the arena (where I could get flipped and caught on the railing) I'd survive. Now, winning is another matter.

I didn't have long to worry, though, as the match was one of the first Kilobot matches. I was called up, got Endotherm's batteries packed, tested the RF, and got in line for the match. After a bit of waiting, we were up.

I went in, set Endotherm down, powered it up, twitched it back and forth with the remote control to make sure everything was A-OK, and walked out, ready to face Defiant. Apparently, Defiant had a problem, as its creator/controller took over 2 minutes inside the arena, with Defiant's arm up, poking around. I was almost ready to celebrate the apparent forfeit, when I saw it move, and the owners step out. Sigh. It looked like I'd have to face Defiant after all. The countdown began, and on "Kick Bot!" I charged forward...

Well, it was supposed to be forward. Instead, it ended up going a bit to the right. I could see my wheels slipping on the floor: traction was not optimal for Endotherm, it seemed. Defiant, on the other hand, used its six-wheel drive to ram me solid. I backed up, and the pushing match started. My goal: stay away from the railing and last the 5 minutes to go to audience vote. Defiant's first attempt to flip failed, as I slid off the side of the arm, but toward the railing. His second attempt succeeded, and luckily for me, Endotherm was far enough away from the railing to miss getting hung up. When Defiant flipped me, the crowd went wild. When I started driving Endotherm upside down, a couple hoots and hollars were heard. Seems I surprised someone. At this time, I reallized I never practiced driving upside down: trial by fire, they call it. So, for the remainder of the match, I practiced driving upside down and right-side up, while attempting to unsuccessfully ram Defiant. I thought I was going to last the five minutes, and the announcer even began counting down from 10 seconds, when I was pushed toward the railing, backed up, and was flipped onto it, hanging myself by the ball-transfers.

4:55. Almost lasted all five minutes. Oh well, I expected to lose to Defiant, and as I took Endotherm back to the pit, threw the batteries on charge, I hurried to the table to see who my next opponent would be. I found out that I had a bye the first round of the loser's bracket, and shouldn't fight until that afternoon. With batteries on charge and no real damage, I went back to the competitor's stands to watch the rest of the morning battles.

Suddenly, while I was watching a match, my father came to me, saying that he thought he knew what could solve our traction problem. Seems the soft-rubber casters Endotherm was using as drive wheels were slightly "domed" on the edge, and as such, only about 1/2 inch of the two inch width was actually touching the ground. We quickly took the spare and decided to experiment.

We headed out to the SORC machine shop (THANK YOU SORC!) with the wheel and a file. The thought was to spin the wheel up and file it down. My teammate originally suggested having the robot drive to motors to full speed, but I didn't want to risk battery drain or electrical failure. At the machine shop, we realized the lathe was right out (wheel was too big, plus it would have been a pain to center in the four-jaw chuck), so we looked to the drill press. An axle through the wheel would have been best, keyed to hold it firm, then the axle would be chucked up into the drill, but I didn't have a spare axle. I did, however, have extra 4.5" 1/2"-13 bolts, and with an extra nut, the wheel was sandwiched in and spun up to speed. After a suggestion from a SORC shop helper (Thanks whoever you are!) the file was abandoned for a grinder, and in minutes both drive wheels and the spare were flat. Traction was improved fantasticly. We now knew that we might have a chance in the next round.

Saturday Afternoon Session

With battles somewhat behind schedule, my loser's bracket match against The Missing Link wasn't scheduled until Sunday morning, so I spent some time checking out Missing Link. It was a modular weapon design (as mine was, minus the weapons, of course) with a large, cut-through-anything, $300 monster saw blade as its main weapon. As I had seen it saw through Spike's (of the multibot Spike of Doom) wheel and gearing, I knew that Missing Link's saw could do some damage to Endotherm. So, I came up with a plan: attack Missing Link with the 1/2 Aluminum "bash bar", which should slow down and hopefully stall the saw, and then attack Missing Link's wheels, pushing perpendicular to it, and hope for the arena blades.

With a plan set, I watched the Afternoon fights, and waited for Sunday morning.

Sunday Morning Session

Sunday came, and after verifying that the batteries were fully charged, I watched the morning matches. My time off wasn't long, as I was soon called up for the match against The Missing Link. As I got ready, I noticed that Missing Link ditched the monster saw blade for a chain saw, and had the scoop on the rear. I knew that if I was scooped from behind, that my drive wheels would be off the ground, preventing me from fighting back. As the arena weapons were functional (and noticably deadly), my teammate mentioned that I should place the optional rear spike on. Problem was, I never really finished the spike design as I needed lathe time. But what I did have was a 12" long 1/2" thick steel rod that was the base of the spike. Putting that on the back prevented being scooped from behind. Satisfied, we got in line.

As I stood in line, I developed a strategy: charge the chain-saw head-on to derail the chain, and then attack Missing Link from the sides. Once the chain-saw was out of the question, I knew Missing Link couldn't harm me. The arena weapons, however, were another story. After a few matches, we were up. I carried Endotherm into the box, tested it out, and headed for the pilot stand. After a few tense moments, "Kick Bot" was heard and the match was started!

Missing Link came at me scoop first. After a few clashes, Missing Link's driver turned it around, and brought the chain-saw to bear. With a 1/4" think aluminum diamond plate front with two 4" spikes sticking out the front, the chain-saw didn't scare me at all. I hit the chain-saw head on, then turned. My spikes (made of 4.5" long 1/2"-13 bolts) grabbed the chain and derailed the saw. Success! With the chain-saw out of the picture, I started to attack the side of Missing Link. Missing Link, however, was very mobile, and we danced in the BattleBox. Several times he got me from behind with the scoop, and the steel rod prevented Missing Link from getting under my drive wheels. After two minutes of pushing, dodging, and repositioning, I got into what I thought was a good position, backed up, ready to hit Missing Link on the side, when the announcer called for the robots to be stopped. Apparently, Missing Link was dead! Endotherm was declared the winner, and I hurried into the box to grab Endo. Jason Bardis, Missing Link's builder/driver, shook my hand, and congratulated me on the match. A BattleBoy handed me the winner's medallion, and I took Endotherm out of the BattleBox. After the camera interviews, I headed to the pit table, checked Endotherm out, and set the batteries on charge. I then found out that Missing Link apparently had a battery cable come disconnected during on of the hits, and that was what disabled it. Seems Endotherm was lucky!

After the putting the batteries on charge, I took a look to see who my next opponent would be. Surprise! Spike of Doom was my next opponent: two proven 25 lb robots. I knew that I would have a challenge. With no repairs to do, I headed to the seats to watch the matches, and waited for the next match.

Sunday Afternoon Session

After lunch, I came back to see that Endotherm's next match was scheduled to be the fourth afternoon match. Batteries charged, Endotherm was put back together. All since the Missing Link match, I had been thinking strategy for the Spike of Doom match. Spike of Doom was a multibot consisting of the Wedge of Doom and Spike. Spike was a fast, mobile robot with a strong lifting arm, recently modified to include a piercing arm on top. I knew that Spike could easily lift Endotherm, although I doubted Spikes ability to drive holding Endotherm. The Wedge of Doom was a fast wedge, capable of pushing and flipping 25 lb robots easily. Spike of Doom lost their first match against Missing Link, who I eliminated the match before. (Seems Spike of Doom's team expected Missing Link to win, so they had to devise a strategy against me quickly.) Spike of Doom then won against RACC, another multibot, then defeated Rasta. I knew that as I only had to defeat one-half of the multibot team, Wedge of Doom was my target. The goal was to push it from the side into one of the arena saws. Time in line was fast, and suddenly our match was up.

It seems that Spike of Doom's strategy was for Spike to pick Endotherm up with the lifting arm, then have Wedge of Doom push the two robots toward the arena saws, where Spike would lower Endotherm into the blades. This was necessary as Spike would not be able to move while lifting a 55 pound robot.

Endotherm's strategy was to push Wedge of Doom into the blades, as only one of the two robots needed to be disabled. Also, Endotherm needed to avoid getting too close to the railing, where either robot could push it onto and have Endotherm get caught just as it did when it lost to Defiant.

Both teams stuck with those strategies the entire match, that is until Endotherm got lucky again. About half way into the match, Wedge of Doom stopped moving, and Endotherm was declared the winner! It seems that Wedge of Doom had a rare motor controller failure. Unfortunately for Spike of Doom, that was their second loss, and were out of the event.

With my second victory under my belt, I found that my next opponent would be Sallad, built and driven by Dallas Goecker. I helped Dallas get Sallad ready for a previous match, so I knew that Sallad was a fast robot with lots of pushing power and a somewhat weak lifting arm.

I also knew that I wouldn't have much time to charge the batteries, so I borrowed Brian Scearce's (maker of Rott-bot) gel-cell fast charger. As I planned my strategy while my batteries charged, the match manager called out for Endotherm. With only 40 minutes to charge batteries (1 on fast charge, the other on trickle), I knew that I would be going into this battle with little energy. Only by luck would Endotherm win, and while it was seeming to get its share of luck, I knew that was soon to run out.

Outpowered. That describes the match. Sallad's arm wasn't working, but he didn't need that against Endotherm. I was pushed all around, shoved into the saws (one even ripping apart a ball-transfer, look at the damage page!), and generally man-, er, bot-handled. One time Sallad wedged himself under the side, and while the crowd was cheering me to hit him and free him, I didn't have enought oomph to do it, and the crowd booed. Finally, after my batteries were so dead, and I knew I had lost, I called the match, before Sallad could do any more damage. I at least damaged one of Sallad's wheels before throwing in the towel. Of course, that's hardly any damage compared to what the saws did to me.

With my loss to Sallad, I had to decide if I was going to participate in the rumble. As I was told that the rumble would happen within two hours, I withdrew from the rumble, knowing that my batteries wouldn't be fully charged. The Kilobot rumble took place about four hours later, though, and while I could have charged Endotherm's batteries up, I didn't take place. I knew that I would just be a target for Missing Link and Spike of Doom, and with Ziggo out there, I knew that I wanted to bring something back home. Part of me wishes Endotherm participated, although it was nice to bring a fully functional robot home.


Well, BattleBots is all said and done. Check out some pictures of the damage done to Endotherm at BattleBots. Man, those arena saws can be vicious. Anyone have any pictures of them?