Another Formula Minisumo...

[slurp]

Just put the PCB version of the 18X circuit on a simple chassis to make this minisumo within the Formula Rules. It's currently 170g (210g with pictured battery) so will need some ballast as well as tyres.

small wheel minisumo to forumal rules

small_formula(SML).jpg (38.56 KiB) Viewed 1032 times

It's got edge detection but there's a little to do on opponent sensors (may use tweaked IS471F tweaked to get medium range) and tyres (gasket goo type). If I can get a smaller battery then I'll get to tuck it in at the back, the battery pictured get strapped across the top.

I'll drop add to the description as I finish off. Done some basic testing on edge detection and drive using the PICaxe Flowcharts for simple programming. So all but done now as I've got to devote some time to the Tamiya and other formula minisumo that was built.

regards,
Colin

[slurp]

Been a slow weekend, getting back into the building and fixing, had to swap out a duff motor/gearbox, added a hook to strap down the battery but really want to find a smaller capacity Li-Poly to slip under the control board.

Looking at the opponent sensor arrangement but otherwise running well. Would like a simple gig to buzz the gasket goo tires to smooth on the drill (the motor doesn't run fast enough for this!) this will take a small rock out of the movement as it drives.

Another Picture....

AFM-01.jpg (48.47 KiB) Viewed 816 times

Not quite as low profile as I'd like but there's a limit to what can be done with the Formula Motors. Once I get those battery and sensor items done I'm looking at a vacuum moulded shell... Inspired by some home made vacuum formers but that's another weekend.

Off to tweak some more.

regards,
colin

[slurp]

Just getting my finger out to fix some minisumo and document some progress with the wiki drawing the various items together: http://www.minisumo.org.uk/wiki/index.p ... laMiniSumo

[slurp]

Still playing with this, I've been tweaking the software a little, also playing with opponent detection.

The big must before the next event it to get the weight up, there's a bit of space under the chassis place I'll have to get some steel or brass in here. (there was no chance that we'd move a resonable opponent on the last outting!)

I've realised that my random circuit reference to connectors needs to be revised. Naming them by I/O has got to be more straight forward and memorable for software and general modification!

regards,
colin

[slurp]

Got to upload some pictures of the chassis mods later, the balsa spacer/mounting block between the gearboxes has been replace with steel and a few strips have been added to the underside of the chassis place. I've a little shaving to do, I've gone just over budget on weight but it'll not be too much trouble to sort.

The chassis will get a spray job to black it up, I'm just considering what to do with the rest of the body.... Stealth!

regards,
Colin

[slurp]

These modifications don't change the overall profile of the minisumo in the earlier pictures. They're only aimed at getting the weight up.

Under-side view of the chassis

AFC-Chassis-01sml.jpg (16.1 KiB) Viewed 538 times

This first picture shows the underside with the ballast weights in place... the front edge needs a little lightening to get back under 500g. The thicker plate is tapped to allow screws (M3) to retain the plates.

Top-side view of the chassis

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Topside show the counter sunk fastening at the rear, this will be under the gearboxes. The front has a pair of standard screws.

View with Gearbox mount placed

AFC-Chassis-03sml.jpg (13.28 KiB) Viewed 540 times

The block isn't quite finished, it needs threaded holes to attach the gearboxes (M2.5)and to allow it to be attached to the chassis plate.

These have been simply cut from a bar with a hacksaw, drilled and filed to clean up edges.

regards,
Colin

[slurp]

Well, this is the finished chassis, a little close for weight the whole lot assembled is 499g... I'm not 100% happy with the sensors so it'll be close and I might have to knock a few grams off with a hole or two if/when I get around to some alternatives.

AFM Finished Chassis

AFM-03.jpg (27.33 KiB) Viewed 529 times

The chassis has had a lick of black spray paint, I'm still considering the best approach the the wheels and gearboxes.

The plastic profiles are used to mount the control circuit, it slips in quite nicely

A few tweaks on software and this is it until Birmingham on the 26th June... I hope it's enough to snatch Peter's title of UK champion!

regards,
Colin

[slurp]

Work in progress...

AFM-04.jpg (25.79 KiB) Viewed 409 times

Still tweaking.... just a picture for progress.

[slurp]

I've back tracked to my short range sensors for Micromouse 2010.... I can't get the pololu sensors to respond reliabily

Still at least I'm rolling and have short range sensing.... (ony 50-60mm!!!)

regards,
colin

[slurp]

The competition at UKMM 2010 gave me a few things to think about:-

• Improve the front scoop and Center of Gravity (turned over too manay times)
• Consider tyre material (and re-consider CoG) to improve traction
• get better range on the sensors
• fix the PCB more securely (displaced several times - I'm sure it impacted on sensor connections)
• fix the PCB connections for sensors

Over all I was pleased with performance, I'm hoping a few tweaks make the difference.

Best regards,
Colin