MBX 2.0 – Part 5

Epically behind at the moment, still haven’t got the wiring done as I’ve had to make a few changes to things. Was having an issue with a decent idea for mounting the batteries and electronics, which is why I haven’t progressed much on wiring the sucker up.

However, have finally settled on an idea to mount everything and I might use the idea for other robots in the future. Basically got my hands on a bunch of high density closed cell foam (Same as the blue camping mattresses everyone uses, but thicker) and will be layering it to fill the entire interior of the robot. The only things that won’t be mounted in this foam will be the drive train and the whyachi switch.

Epic rats nest wiring, will just duct tape most of it to the motors and jam the lid on to keep it in place.

Spinning, but not translating too well, so working on what the problem is, one drive has started to bind, looks like a bearing block might have shifted in an impact. Last resort will be to retro fitting everything back into the old 1 wheel version and run 40v to get the speed and spin up. to a decent level.

Eventually I found out why the drive on one side locked up. A collar on the pinion gear that holds the gear from popping out of the bearing broke off and went into the armature and the jammed the whole show up. Dinged up a few of the leaded plates on the armature, so I have removed the motor and left the mountings and the bearing block to run the wheel as a castor. This seems to work fine when spinning, and works just like the 1 wheel version, but spins up on the spot instead of eliptically wobbling around till it gets up to speed. Now that I’m back to 1 drive motor, the voltage is going up to 39.6v like in the testing after RoboWars.

Found half the problem with the translation not working, I found that somehow the model programming for MBX in the spectrum had activated some wierd ass mixing of several channels, and I couldn’t remove it (I can’t find the manual to read how), so I made a new model settings for it and it seems to have fixed half that problem. Just need to work on calibrating the parameters of the accelerometer now to get the heading LED to work correctly.

Things are looking less bleak, so hopefully tomorrow I’ll have it running right, I’ll bring the old version just in case

MBX 2.0 – Part 4

The motors and wheels are now all mounted to the base plate.

Made the first tooth today, it’s made out of 8mm thick car leaf spring. Will bolt them onto the shell with 2 or 4 x M12 8.8 bolts.


Drives are all done now, working on the meltyboard tonight, going to load the new code and start wiring it up. Need to work out if I’m going to have enough space for 2 x 10cell packs in parallel and still fit all the electronics, i’d prefer two packs in it because with the 1 motor on 12cells got the batteries pretty warm after 3mins of testing, so 2 motors might just be too much for 1 string of cells. I’d never have thought I’d see the day I’d have 20 x A123 cells in a featherweight

MBX 2.0 – Part 3

Had epic dreams of using the oxy at work to bend it all into shape, ended up just slicing it up into sections and welding it. Not one side is at the same angle, but that’s normal for me Laughing Will take my time welding it now to avoid taking all the temper out the hardox, and will cut the base plate to suit it after that.

Shell welded up completely, base plate cut out and hammer press fitted inside the shell. Will weld in some tabs to bolt the base to the shell tomorrow. Will mount the internals during the week and move onto wiring it up

MBX 2.0 – Part 2

New version fits inside a 350 x 350 octagon, which is surprisingly small even when compared to the old test frame which was 260 x 370.

Comparing the old with the new

Another angle, will end up about the same height, maybe a fraction less

Close up, still plenty of space to add various things and make changes in the future.

According to CAD, a full 3.25mm hardox shell would be 7.2kg, just a fraction too heavy, replacing the top lid with 1mm stainless brings it down to a healthy 5.4kg, which leaves a good 1kg for some nasty teeth to weld on

MBX 2.0 – Part 1

Finally kicked off the work for MBX 2.0.
Finished the gearboxes today, made some new shafts and realigned the gears a bit. Layed the parts out and it looks like it’s going to be nearly as compact as the 1 wheel version. I believe it should all wedge into a 350mm x 350mm hexgon or octagon shape.

Some rough calculations based on voltage, gearing and wheel base predict that it should hit 1250RPM, a good 500-600RPM more then it showed @ RoboWars. I’ll have the accelerometer working this time, so it should be much much more driveable and it should translate faster with two wheels.

Will start on the hardox body next weekend.

MBX – Post RoboWars

Alright, a quick report before I disappear into the glow of a blue luxeon LED for a few months….

MBX worked really well for what it was (a glorified testbed built in two weekends), it was pretty lame in combat, as I spent most of the time adjusting the LED header due to the last minute hack to due to destroying the accelerometer before the event. It ran between 500 – 750RPM at various stages during the weekend and showed that it can pack a punch.

A brief list of things to do.

– move to two wheels – helps balance and spin up time, was only 1 wheel because of time restraints…
– more volts – after the event when I ran it on 12cells (39.6v) it was really kick ass, hitting around 1500rpm (but totally undriveable due to my current code limit of 1200rpm….)
– make it round – it ended up square because I built the thing in a day with what was laying around in the shed, next time it will be round for lower wind resistance, harder to jam in a corner and better for hitting with.

The future specs:

Armour: 3.2mm Hardox 450
Drive: 2 x 12v 340 Winch motor @ 33v geared 3.6:1
Electronics: Spektrum + AVR ATMEGA168 + SSR + MMA2300D 250G Accelerometer
Batteries: 1 x 33v (10cell) A123 Packs
Weapon: Translational Spinner, 13.6kg @ 1500RPM = Lots of Kinetic energy

I look forward to bringing a much better, combat ready version to the Ideas Festival.

The Melty Brain eXperiment

I built this robot in like two weeks while suffering of the flu, so very little was documented at the time.

Melty Brain eXperiment or MBX for short.

General Information:

Armour: 8mm/3mm steel, 5mm aluminium & 1mm stainless
Drive: 1 x 12v Winch motor @ 39.6v geared 3.6:1
Electronics: Spektrum + AVR ATMEGA168 + SSR + MMA2300D 250G Accelerometer
Batteries: 39.6v from 2 x 19.8v A123 MEC Packs
Weapon: Translational Spinner, 13.6kg @ 1500RPM = Lots of Kinetic energy
Weight: 10.8kg

Test Video



Needs work, but it’s progressing fairly well. It’s come together amazingly fast in just 2 weeks…