Rewiring the Wheels

The wires I had were too short to reach the ESC on one side. So I took this opportunity to make everything a little neater.

I soldered the + wires of each motor together and the – wires as well. These were then soldered to a 2 pin connector and all covered with heat-shrink.

Don’t forget to put your heat-shrink on BEFORE soldering šŸ˜›

New Battery Monitor


After killing my batteries, I decided to invest in a battery monitor. I pickedĀ up a 2-pack of these from Amazon Here. They give the total voltage, and the voltage of each cell (up to 8!)

These things are pretty light-weight. But not quite light enough for me to always have it in the bot.

Reviving My LiPo Batteries


So I messed up. I let 2 of my 11.1v batteries drop down to ~7.5v šŸ˜¦

ThankfullyĀ Frederick Moore, the creator of Road Rash, answered my call for help on the Combat Robots Facebook page and graciously took the time to walk me through the steps of bringing my batteries back to life.

First, we set my charger to Pb Charge mode and started to charge the battery set to 10v at .2 amps. The charger thought my battery wasn’t capable of 10v because of how low it was and wouldn’t charge it. This was fixed by setting it to 8v, letting it finish, and then going to 10v. Then I would let it charge on 10v for a few minutes until the battery was at a stable voltage again. It was normal LiPo charging from that point on!

It was also very important to make sure that each cell’s voltage did not get to high while Pb charging. So I just walked the volt meter across the balance connector every few seconds to make sure they were ok.

At the time of writing this, I don’t know how damaged the batteries currently are. I’m ordering 2 more Zippy’s just in case. And from now on, I need to be more careful with my battery usage.

4-Bar “Cobra Stance”

Remember when Lucky took a hit from Beta’s hammer and knocked its flipper in creating that “cobra stance”? Check out the full fight Here. Well this happens when the rear section of a 4-bar flipper rotates too far forward.

The happened to my bot during testing. The rear part doesn’t want to rotate that far mechanically, but the inertia from the arm going up causes it to rotate a bit further than expected and then bend back into place.

This should be an easy fix of adding a brace to prevent it from physically rotating that far.

Removing One of the Servos


So I decided to go ahead and go with only 1 servo. This will save me about 2.5oz of weight from the servo, and another ~ounce from the removed aluminum and UHMW. It also makes Torsion 1″ less wide. Which is better in my opinion. The only slight annoyance out of this is that the arm is now offset. But hey, gives it some style I suppose. Shouldn’t affect the lifting much.

Transmitter Button Hack

So if I want my lifter to go all the way up, I need to push the joystick all the way up of course. But that takes a bit of time. It is easier and even makes the lifter go a little faster by using a push button for a full on/off toggle.

First, I opened up the transmitter (just a few screws). After finding the leads of the pot that I wanted to hook up to my button, IĀ soldered them to the button.

The button is just a simple push button. My transmitter had these pieces on the back (See the final picture for a good look at them) that fit in between the 2 halves of the transmitter. So I just took one out, drilled a hole in it, and glued the button in place. The plastic on the back of the black piece didn’t allow for a nut to fit on button, thus the glue.

Closed it all up and it works great! Plus I can still use the stick like normal if I need more control for some reason.

Once Again, Too Heavy


*Sigh* Overweight again. This doesn’t even include the top armor and the wedge. Though it is a little heavier because of the big battery I’m testing with and I could probably drill out some of the arm. But for now, I think it’s time to drop one of the servos. The HXT12kg should have 250oz-in of torque at 9v. Which should be enough one its own.