Clash Of The Bots 2023 Recap

BIT 1.36 V3 has competed in Clash Of The Bots 2023 and went 1-2. There are things about the robot that has performed better than I thought, and some other things that I didn't expect to break. I'm overall happy with the robot and there are a lot of immediate improvements I can make. We will talk about them in this post. 

Drivetrain

The two-stage custom gearbox did not have any failure, but it seems like the brass pinion gear on the motor is wearing down and there are metal shavings building up on the belly pan. I am not sure if it will stop producing shavings at some point or will it just chew the gears down eventually, but the immediate fix I can make is a better gearbox enclosure to keep the metal shavings away from the electonics. 

Toward the end of the run, the internal spur gear of the wheel seems to be wearing down a little. When you turn the wheels back and forth by hand really fast, it will skip one tooth. It is no where close to being a problem and you cannot feel at all when actually driving. But this shows that the wearing on the internal spur gear could be a problem in the future. 

Another thing about the drivetrain is traction... The floor at the event is some sort of glass fibre and is very slippery. The front wheels of the robot (which happened to take the majority of the weight) is made out of TPU and does not have any real tread. The rear wheels are fine since they are silicone wheels, but they are not supporting a lot of weight of the robot, so they can't get a lot of grip either. These two reasons combined makes the handling TERRIBLE. In my second match against a lifter bot, I tried to aim at the opponent and run into it, but ended up circling around it and can barely land any hits. One fix to this problem is to make the front wheel silicone as well, but because of how small it is, it will be really hard to do. 

Weapon

I hate set screws. 

This time we moved away from smooth aluminum pulley and used 3d printed timing belt pulley. This puts more torque on the motor pinion pulley, and the failure point was the set screw that holds the pulley onto the motor shaft. In two of the fights, the motor was still spinning but no power was transmitted to the weapon because of the loose set screw. 

Annoyingly I can't really find an easy fix for this problem. The motor shaft is so thin that I can't buy a replacement with keyway in it. I might need to use a dremel and sand the shaft down to a D shape so that the set screw can sit on the flat side. 

Link

My link got cut off by a horizontal spinner... again. Switching to a switch might be a better idea. 

Bellypan

A drum hit me on the bellypan and sent me to the ceiling. It took a huge chunk out of my bellypan and I was 1mm away from a battery explosion. I am overall happy with the strength of the bellypan... It was a pretty big hit. 

TPU Armor

The armor I ran this time is 98A TPU and it lasted the whole event. It took some BIG hits but the damage is very much cosmetics and I'd say it can probably last another couple matches. 98A TPU seems to be very durable in this weight class.