2022 NHRL July Event Recap

The second beetleweight robot of the team went to the NHRL July Event this year. I got two wins and two losses, and had some really fun experience. In this article I will talk about the matches and fun stories behind them. 

The first robot I went up against is Odachi. Odachi is a new robot and it's their first event in NHRL. It is a four wheel vertical spinner, a design similar to Biteforce. It is a really well-built robot with an amazing look. 

Before the match start, I found that my weapon motor got stuck for some reason. I took it apart and found that all the bolts holding the motor came off due to vibration coming from the weapon, so I put loctite on all of them. It's really lucky that I found this problem before the match, other wise it would be a disaster if it happened during a match. 

My strategy is go weapon to weapon and hope to break its weapon in exchanges. I have confidence in my weapon reliability because the bearings on it are very beefy for this weight class and it barely puts any stress on the motor because of the smooth pulley. 

In the match, Odachi lost its weapon pretty early in the match. But I wasn't able to land a good hit due to Odachi's fork geometry, and the weapon wasn't running at 100% because the belt is slipping. About two minutes into the fight, Odachi's weapon came back to life all of a sudden. I decided to keep on doing weapon exchanges and Odachi flipped over and the match went to the judges. We won the first fight! 

The robot wasn't damaged at all, except some scratches on the weapon motor. But there is something wrong with the robot performence. 

Firstly, the drive handling is weird at low speed, I ran into the wall all the time. There isn't really a fix to this. The handling at high speed is fantastic though, the gyroscopic force of the weapon is actually beneficial to the handling. So I guess the only way is to avoid running at low speed. 

Secondly, the weapon belt was slipping pretty badly. I got a sharp screw driver and tried to make the pulley surface rougher so the belt can get more grip from it. It did alleviate the problem but it was still definitely not giving out all the power it has. I though maybe I can put some coke onto the pulley surface and it would get sticky after the coke dry up. And it alleviated the problem as well, but the weapon performence was far from satisfying. There was't a lot I can do about this during the event. 

The second robot I went up against is Mechanical Advantage. It is on a 21 winning streak at that point and it's their first time coming to NHRL. So to be honest there isn't a lot of hope for me, especially when my robot is not at its 100%. 

The strategy is to get around to its side using my speed advantage. So I really need to stay focused and calm, and be careful with where I'm going to. 

I did managed to get a hit on its side at the beginning of the match but the bad handling at low speed gave Mechanical Advantage a really good chance to hit me on the side and they didn't hesitate to take the opportunity. I lost my mind at that point, and forgot about the strategy. I consistently went weapon to weapon and lost every single one of the weapon exchanges. I went pretty much the same way for the rest of the match. Luckily though the robot was electronically fully functioning for the whole time. I was knocked out ten second before the match end, because I was high-centered on the wall. 

The damage was pretty servere, all the TPU armors needed to be replaced, the battery was deformed, the frame took several direct hit but its functionality wasn't affected, the carbon fiber panels were splitted and needed to be replaced. One interesting thing is the failure mode of the TPU armors. On my first beetle weight, hits would normally take chunks off of the TPU armor, and they can last for a long time. But this time I switched to a stiffer type of TPU, and printed at a much lower infill, so they were actually torn part horizontally. I should probably switch back to the softer TPU and make the infill as high as possible. 

I'll talk about the next two fights in the next article.