Well, it doesn't look like I'll ever finish that build report video, so I'll just fill in what happened at the event here instead.

So the final few days leading up to the event were entirely focused on three goals: losing as much weight as possible without weakening many of the key structures, fitting the front claws, and finishing off the electronics. For losing weight, I opted to drill holes using a hole saw in the lifter spines, the rear curves on the machine, at the front of the base plate (though leaving enough space around the front motors so as a nasty shock wouldn't snap the plastic), on the back plate, as well as hollowing out the lifter supports/bulkheads.


a shot of the machine with the front claws mounted, as well as the holes in the spines and sides

After about a days worth of cutting and a years worth of swarf, the front claws were done. They were mounted simply to the base with two bolts each, and while I was worried about how much pressure they could take, they seemed to hold up well. They also gave me an idea of where I could mount the electronics within. A safety loop was added before the main circuit (link, 60A battery fuse, LED power light), 30A fuses were installed before each ESC, and a 20A fuse was added to the linear actuator. figuring out how to mount the battery was tricky given weight limitations, so for a small event like Mechatrons, I opted to cut out a slot in some corregated cardboard that would hold the battery snugly, and use velcro ties to keep everything in place. The end result wasn't the tidiest, but it weighed very little, and could survive a few tumbles.


a shot of the electronics prior to the event

With everything in place, I decided to test out the force outputted by the linear actuator by "grappling" some weighing scales. I decided to stop when I read 55kg on the scales! Unfortunately, another test against a small, thick cardboard box placed too much pressure on the center of the green piece, causing it to crack. Frustrated at this, I ended up needing to cut an extra piece using some offcuts to reinforce the vulnerable area, as well as a few extra nuts and bolts. Despite this however, I was actually slightly underweight from all of the holes, and after finally caving on drilling holes on the front piece of the robot, all that was needed was the metal sheet up front and something to stop it getting beached.

DAY 0

We drove down from Galway on the day before the event, and ended up being one of the earliest teams to arrive (team might not be the right word considering I was the only person at the event who had anything to do with it prior but whatever). I met Peter, Zulu, and many of the other crew members, and was given a place in the pits right where the guests wait to be allowed into the show. Much of the first part of the day was spent setting up and oogling the new King B (partly because it was one of the only other heavies there at the time, and partly because, well, it was the new King B).


Barróg from the front


Barróg from the back

Another shot of the innards


An example of Barróg doing what it was built to do

A few things to note from the new pictures. The holes and the support piece along the front ended up looking a lot better than I thought they would; in fact, if I had known even a week beforehand how the holes would have looked, I would have drilled a whole lot more! I ended up ordering two sheets of metal that were fairly cheap for the front, and the 1.5mm stainless steel could get very low to the ground without catching on anything, and if that would be an issue, I made it a policy to keep the lifter slightly open while driving. I settled on threaded bars along the sides which would prevent Barróg from getting beached on its side, but would not help it if it were stuck 45 degrees upside down (ooo... foreshadowing...). Ultimately it came down yet again to time and weight, which by now have become dirty words to me.

I was a little anxious coming up to the safety check that not having a locking bar for the claws would disqualify me from fighting, though I had gotten reassurances from Peter Redmond that the slow nature of the clamper would allow it to avoid this rule. I had a threaded bar with me, and would have been able to drill holes in the front claws where they meet the green piece so as to prevent the machine from opening, but this would have been an untested option, and could have led to the front claws breaking, or the actuator just breaking through its mounting. After using the machine, I highly doubt both of those things could happen, but it was something in the back of my head at the time.

The safety inspector went through the operating procedures of the lifter and, fortunately enough, there was no problem. What DID end up becoming a problem for me however was the transmitter I was using, a modified Devo 7E, which decided, for the FIRST TIME, on that VERY DAY, with NO WARNING, that the power switch being set to the "off" position wouldn't turn the machine off. With this, I wasn't able to demonstrate that in the event of a loss of signal, the machine would turn off. If I couldn't do this, I would be disqualified from competing. In theory, I could have my batteries hanging out of the transmitter, and just disconnect the lead connecting the two whenever I wanted to show the events of a loss of signal, but fortunately for me, before having to resort to that, I was able to get help from Jamie of Team Coyote and Tony of Team Rusty, and was given a loan of a spare Spektrum DX6i for the event. The robot was rewired to work properly with the new transmitter, and I could pass safety. I was good to go for any fights tomorrow!


The faulty transmitter, which stopped turning off for me


The Spektrum DX6i I used for the remainder of the event, which worked like a charm


A shot of the Arena the night before, looking uncharacteristically smooth. Rest of event report to follow soon.