Forklift Certified
Jack Poulos Nick McKinley Madeline Mrozek
Sketches & 3D Model
Our team decided to make a bot inspired by a forklift. We took inspiration from Tombstone and Bronco from BattleBots. The overall form of the bot would be a rectangular prism, with the front having the forklift weapon and the back would have a horizontally-spinning saw blade. The forklift would be powered by a pneumatic system that would act as a flipper, which would be able to launch other bots into the air. The saw blade would spin at a high rate and would be intended to either cut through metal and/or hit bots back as a defensive mechanism. The general idea was to have both sides act as offensive weapons and defensive deterrents, with only the sides being vulnerable to attacks.
Chip Board Bot
Building the chipboard bot was simple to make. The main body was made from laser cut chip board parts, and the 3 motors for the wheels (2) and the saw blade (1) were held in with 3D printed motor holders that were hot glued to the body. When testing the drive of the bot, the chipboard model was able to glide across the floor due to its light weight and fast motors. When testing the saw blade, the blade was able to spin fast without hitting the bot's side and had little trouble with adjusting speed and keeping balance on the motor.
Metal Bot
Beginning work on the metal version of the bot led us to scale the bot larger. The original dimensions of the bot was 6" x 8" x 3", however, once we tested the pneumatic system inside the bot, we realized that we would need to upscale the bot by at least an inch to accommodate for the pneumatic system (mainly the upright pump), and the rest of the components inside the bot if everything was going to fit inside. Our metal bot ended up being 8" x 11" x 4" with the same layout as the original version.
We were able to plasma cut the parts out and MIG weld everything together. there was one side of the bot that did not cut long enough, but we were able to fix it by welding an extra piece of mental to the corner to cover it up. The motor holders were still 3D printed, but were now screwed into the bot to keep them secure, and the screws that stuck out of the bottom of the bot were angle-grinded off. The motor holder for the saw blade was attached with a metal zip tie that went through two slits that were cut into the back of the bot.
The top of the bot was cut to leave open spaces for the forklift and saw motor holder. We welded in two brackets for the top to lay on, then welded two upside down screws to the brackets to help hold the top in place. we then cut two holes in the top piece that would slide onto the holes and keep the lid in place. Doing the lid this way would not require any tools to remove the lid itself, and it would stay in place with two main points to hold it on.
Logo & T-Shirt
We made a custom logo for our team, deciding to use colors similar to the Diablo saw blade so it would match the bot. We looked at a few versions of typefaces and logo design ideas before we came up with the red label with the saw blade logo. For the back of our shirts, we decided to have the HackBerry robotics logo with a section of our last names that matched our logo, then a list of sponsors. Our "sponsors" were Berry College, the Berry College BITS program (the three of us work in BITS), ChatGPT (for confidential reasons), and Diablo (because of our saw blade). We also decided to include a meme of our old boss, which we put at the bottom of the shirt. We made the shirt with a heat press in-lab.
Pneumatic & Saw-Blade Test
We had some trouble figuring out the pneumatic, but eventually with some tweaking, it was able to work several times in a row before the carbon cartridge would run out. The saw blade did not need as much work as first, and once we put it on, it typically was able to work and spin very fast for a while.
We attached the pneumatic pump to the forklift, so it would shoot up into the air by flipping a switch on our controller. However, after some more testing and tweaking, a valve on the system broke and we were unable to replace the part before the final fight. We tried a few different ideas to fix the pump or to at least make it work one time at best. However, 2 days before the final fight we decided that we would not be able to get it to work, and after we weighed in our bot and found it to be slightly overweight for our 12 pound class, we decided to remove the pneumatic system all together and just have the forklift attached to the front to act as a rammer.
Performance Test
Our performance test went fairly well. The saw blade and wheels worked for the beginning of the fight. However, towards the end of the test one wheel fell off and the bot could no longer move. After a few more seconds, the saw blade was spinning so fast that it came off of the motor and flew off of the bot, losing two teeth in the process (one tooth notching itself in the pneumatic pump, which was one reason that led to us not using it in the final fight). Afterwards, we discovered that the saw blade has a top speed of 8,000 RPM, but we were attempting to spin it at 20,000 RPM, which could have been the reason for it flying off. However, the bot was able to perfectly complete the test with popping all 5 balloons and destroying the banana.
Paint & Colors
Problems & Fixes
One problem we constantly were dealing with was getting the wheels to say on. Almost every time we tested FLC, the tires would come off, the hex would snap, or the wheels would just not be tight enough on. Eventually we came up with laser cutting wider hexes to keep them from breaking and we hot glued the tires onto the rims so they wouldn't slip off. We eventually 3D printed a stronger version retention collar to keep the wheels on, but after those broke, we decided to use the metal ones and weld them on to the wheels for the final fight. We also welded on the saw blade, and when needed we angle grinder it off to get to the internal components of the bot.
Final Adjustments
After removing the pneumatic entirely, we decided to add more to the forklift and we welded on two prongs and a wedge to help with ramming. We also made some minor adjustments to the motor holders and made them a little thicker so not to split while the bot was moving and while a lot of torque was on the wheels. We also added some washers to the saw blade motor to keep it lifted off of the metal top, and we shaved down some areas below the bot so it wouldn't scrape on the ground.
Fight Night
Fight night did not go well for our bot. For our first fight, neither the wheels nor the saw blade was able to spin, and we were pretty much still in the arena for that fight. In between fights, we attempted to fix the wheels so they would correctly attach to the motors better and spin, and we rewarded some parts to the wheels to help keep them in place. For the saw blade motor, we were unable to figure out exactly why it wasn't spinning, but the motor appeared to work fine, so the problem was likely either the saw blade being bent out of shape from heat applied on it during welding, the saw blade touching the top of the bot, or some welding on the saw blade was preventing it from moving. For the second fight, the saw blade was still unable to function, but only one wheel was able to spin for a minute before the motor began to smoke and we could no longer move the bot. The final fights for FLC was the first time we had experienced trouble with both our weapon and our drive function at the same time.
Next time, one of the major issues we would try to get fixed sooner would be the drive and weapon functions of our bot. If possible, we would also like to get the pneumatic system working and functional for a fight. We would probably also redesign the body a little better and look at placing the wheels on the inside of the bot so as to help keep them in place. Another option for improving our bot would be better quality of motors and the overall build of the bot.
