RogueTwo Robots

**RogueTwoRobots** · 19th March 2015, 22:54

Drum selfie! It's what all the cool kids are doing these days (I sound so old).

Update

So as you can tell, I got my hands on that beautiful piece of engineering today. Didn't come until lunchtime though so in the morning I spent a bit of time ticking a few odd jobs off the list, such as drilling the holes for the link mount, starting to reassemble the drive motors and spare, and fitting the power LEDs. Same as last year but slightly different arrangement. Will kick out a fabby blue again:

Also received the correct boring head & toolset today so, after a quick Youtube tutorial on how to set up and adjust the equipment, I was able to make the brushless motor mount. It's a piece of 15mm thick ali from last year's chassis, hence the old drill holes & threads showing up:

But once the motor's mounted you don't see them, so it's all grand. I've seen a few folk machine similar mounts for their brushless motors to add a bit of support, but they tend to accommodate the taper on the front of Scorpion motors. Mine isn't quite as sophisticated but the motor is a mildly snug fit so hopefully it will be of some benefit:

The motor mounted in the robot, the pulley lining up with the groove in the drum tube. The reason for flipping the motor around like this compared to previous years was to, a) do away with the pulley on the drum, b) get the tooth on the far right closer to the bulkhead and, c) let me mount a bearing into the side bulkhead and support the far end of the brushless motor. Due to the positioning of the teeth though, there's quite a gap between the end of the motor can and the bulkhead, so I might leave that last task for now. If I've got enough time, I'll fit the bearing and extend the motor shaft but I haven't supported the end of my brushless for the past three years and not had any problems so will see how it goes.

With the drum and boring head having arrived I was also able to bore out the holes for the drum shaft to mount to. Was worried about things not lining up or drilling holes squint but seem to have fluked it well enough that it's straight and even. I was also worried about how heavy the drum would be, as it's 5.5mm wall stainless tubing with Hardox stuck on top, but when I chucked it on the scales, it was only a couple of hundred grams heavier than the old drum, so 2.3kg in total. I was maybe hoping for it to be a little heavier (Calculations? What are they?) but the reality is that it most likely saves me from having to mill the chassis to within an inch of its life to get it in weight.

So with that, once the drum was mounted I threw the whole bot on the scales:

Definitely not as bad as I was expecting. I'll claw a couple of hundred grams back when I trim down the front of the bulkheads to expose the drum some more, and can take a chunk out of the rear bulkhead to save some weight too. Accounting for various other fittings and such, I reckon that'll leave me 3kg for the armour. Not 100% sure what I'm going for in that respect yet but it won't be a full Hardox jacket anyway. Most likely a combination of steel and HDPE. But we'll see how that goes.

I'm back up the road tomorrow so that'll be the extent of the updates until next weekend.

**RogueTwoRobots** · 19th March 2015, 22:58

Originally Posted by Eventorizon

He will probably go after me first so don't worry Sam, you will have time to watch me get ripped apart before Drumroll turns Hatchet into the insides of a bean bag :-P

Well I'm hoping that you go after Hatchet, leaving me free to attack your bot's backside. That approach seemed to work pretty well last time we fought

And cheers for all the comments about the drum; huge thanks and all credit to Kenny/ALK Engineering for the top-notch work he's done.

**mrsam** · 19th March 2015, 23:36

Originally Posted by RogueTwoRobots

Well I'm hoping that you go after Hatchet

You suck, that is all

**RogueTwoRobots** · 19th March 2015, 23:42

**Mouldy** · 20th March 2015, 12:36

no banana for scale?

**RogueTwoRobots** · 29th March 2015, 22:55

Update

I was back home over the weekend there so managed to get a few more bits and bobs done.

First up was replacing the burnt out/damaged 775 motors from last year and getting all the gearboxes reassembled, then soldering all the tails on. Also soldered connectors onto the new TZ-85s and lipo packs, so everything's ready to go on that front:

ESCs snugly fitting in the base of the robot:

Put everything in for a quick drive test today and discovered a slight bug in the drive setup. One TZ-85 is self-programmed, one is a BotBitz version. Turns out the codes used have slightly different parameters as one wheel starts before the other and at a faster speed (even when trimmed out). The BotBitz one starts more slowly and has better low-range control, but doesn't seem to go as fast at full speed judging by the sound of the motors. The self-programmed one has poorer low-range control and starts out a bit faster. End result is that the robot is currently pulling to one side when driving. I'm assuming that I can just reprogram the BotBitz one with the self-programming code (and reconnect the middle wire) so that both ESCs behave the same and the drive is more balanced.

The weapon belt(s) also arrived so I was able to rig up the motor and drum. First fit was ridiculously tight; the drum spun but it was putting a huge strain on the brushless motor pulley. So I milled a small chunk off the edge of the brushless mount and turned the bolt holes for it into slots so that it could slide a bit closer to the front of the robot. This, along with cleaning out and oiling the bearings, made for a much smoother spin-up. It's still ever-so-slightly on the tight side but once it wears in a little it'll be fine.

And for those of you who haven't seen it:

So with everything in place I chucked it on the scales with the old Hardox armour from last year:

Not bad! The only thing left to add are the top and bottom skids which will be Nylon so won't be that heavy. The top panel will probably drop down to 5mm and, although I'm still not 100% sure what I'm doing for armour yet, it certainly won't feature the slab of 5mm steel that makes up the back panel of that Hardox armour, so that, along with still having weight-shaving options on the ali bulkheads, means that it should comfortably be in weight.

Also made a start on retreading Reaver's wheels with bike tyre. No more worn down Banebots wheels needing cleaned after every fight!

Only managed to get two done before having to head back up the road, but I like how they're looking so far. Gives it a bit of an all-terrain feel.

So that's that for now, got four days of work (woo, public holidays) then I'm back down for the mad rush to get everything finished before heading to Birmingham. Usual onslaught of pictures and text shall resume then.

**harry hills** · 29th March 2015, 23:13

Aw yis. Love me some drumroll.

**Eventorizon** · 31st March 2015, 06:19

Something doesn't sound right in that video, like there is a lot of friction somewhere... Looks great but its not as smooth as past years.
Still looking good though, some nice exposed Aluminium to chew on at the front