Well, it's the end of the line for the heavyweight Savage Toaster, (or is it?), but the insides of the world's most dangerous kitchen appliance
are being transplanted into Ka-Pow!- a new wedge-shaped design. This not something I'm entirely happy about, but the fighting robot scene
has become extremely competitive and the surface area of The Savage Toaster was just too large to armour effectively. Lots of time and several
competitions have passed by trying to reconcile the way I wanted the machine to look with the functional requirements of a fighting robot.
Ka-Pow! does look quite good though, and I'm quite pleased with the name! The real step forward this year hasn't been so much the new shape as a
new team member. Possibly even a team merger. With Stuart tied up with various projects related to his degree course, and Richard adapting to
being a dad (hi Ollie!), the team was effectively just me and Tracey, with Keith on the website. Luckily Alan Wood of Team Onslaught, who'd
already kindly helped with machining the drive train on The Savage Toaster 2, agreed to step in for the build for the FRA World Championships. After
a lot of talking through various options, lots of coffee and chocolate biscuits (vital to the creative process...), and endless Blue Peter-style cardboard
models (you'll need an empty cornflakes box, some sticky-back plastic and you may need a grown-up to help cutting the shapes out...), the first
version of Ka-Pow! was thrashed out. Compared to my own laborious pace, Alan works very quickly, and even before the shape had been finalised
he'd already prototyped the modified ram for the flipper. What I'd asked him to look at was the possibility of adding an additional port to our
low-pressure ram, to double the flow- probably involving a new end-cap on the ram's base. What actually happened was that Alan enlarged the
existing port to accept a huge quick-exhaust valve used 'backwards' as an inlet, fed by a large low-pressure buffer tank via a hose with about six
times the area of standard 12mm pneumatic tubing! The new system looks likely to be able to punt opponents into the air in the style of, say, M2
or Chaos 2. Alan has also casually mentioned the possibility of a scratch-built high-pressure ram as a future option, but this is unlikely before the
World Championship event.
PBQ 9Ah batteries have been acquired, and I'll shortly be trying the Toaster's chassis at 36v before stripping it down. Alan has already welded
up a basic chassis (as of the 29th of June) and I should be taking delivery of this on Tuesday July the 6th. This leaves only three weeks to get a
basic running robot- I feel we have to get it to this point by the end of July. Past experience suggests that this will not be easy! On the other hand, all
the major sub-assemblies already exist and work, and the armour panels involve no curves! The final weight of the 'naked' robot will determine
the armour used.
As always, it takes longer than you think, but Alan has already put together the new shock mounted sub-assembly for the drive system. This will comprise the motors, wheels, chain tensioners, speed controllers and radio receiver. All the major elements of the pneumatic system, apart from the buffer and the extinguisher, have been hung off the ram itself. Clever stuff. The main issue now- apart from the little matter of assembling and testing the thing- is getting the armour on it. I've just spent a couple of long evenings getting the panels worked out. 3mm mild steel will be cut and partially welded in the last week of July, and more will be done in August. Once it fits and all the 'oles are drilled, we're having it case-hardened. We should then be close to a complete kit of parts, which allows us a gentle, relaxing two-week build for the FRA World Championships!
Well, there's been a lot of water under the bridge since July- most of it not related to robots... Still, the main thing on the robot front was the cancellation
of the FRA World Championships, which took the wind out of the sails of the British builders who had been building machines for this event. It didn't
exactly fill European and American teams that had committed to travel expenses and holidays with joy either... Full marks to the organisers for making
the attempt to fill the hole left by the cancellation of robot wars. Unfortunately this failure made it all too obvious that the days of fighting robots as a
mainstream interest were past. In standard Team Toaster style, Ka-Pow! wouldn't really have been ready- well, it might've run, but not competitively.
Fortunately, Roaming Robots' excellent Winter Tour has gone a long way to restoring the confidence of builders that robots do have a future in the
UK, albeit without the level of visibility afforded by Robot Wars.
Ka-Pow! was already built by September, at least in terms of the main sub-assemblies. Alan took on the job of connecting up and testing the
pneumatics, along with final layouts routing pipes and cables. Meanwhile I finished up an Open University course and a few unavoidable domestic
chores, including knocking down a wind-damaged wall. Hard work, but an excellent excuse to get busy with a sledgehammer...
A couple of weeks ago, we gave Ka-Pow! its first real test. A dead moped that Alan just happened to have about the place was loaded onto the
flipper. We later checked the weight of this model, which turned out to be 80Kg. Flipped the switch on the transmitter and the moped went a couple
of feet into the air off the end of the flipper! Nice... Sadly the moment was not caught on video, but we plan a re-run soon. It repeated this trick a
couple of times and we tried out the self-righting. This didn't go as well because some idiot (me) had forgotten to bring extra gas. Alan has previously
had the shell self-right without the drive system attached. We also took the robot out to an industrial estate to see how it drove. Well, quite fast on
36v, but the batteries seemed to run down pretty fast too. The tarmac surface was uneven enough to beach Ka-Pow occasionally, and ground
clearance was too limited for it to run on its front castors, so it was mostly running on bolt-heads! Straight-line stability seemed pretty good, despite
the gyro being left unconnected. Because of the lumpiness of the test area, handling was difficult to assess, but seemed promising. Next time we
intend to jack the front end up on bigger castors to get a better idea of controllability and battery endurance.
As things stand the power of the flipper seems fine, but the 'hood' or 'hat' on top of the robot needed to cover the ram and provide an attachment
point for the rams rod pivot is too tall. Presently the robot has a tendency to get stuck on its side, in which position it won't self-right. We may be able
to add protrusions to encourage it to roll onto its wheels or at least onto its back. If not the obvious solution is for Alan to build the high-pressure ram
he's threatened. At a stroke (pun?) this would add a tremendous amount of power to the flipper and either greatly reduce, or even eliminate the 'hat' at
which point the robot should roll over. Equally there's a simple, but in this case expensive, solution to the battery issue- go Ni-cad. At 24v this would
allow us to use the existing gearing, save about 3Kg even over the PBQs, and provide more current. Ewe 2 seems fine on this sort of set up. I'm
wondering if there's a bit of old hi-fi I can sell to finance this. Maybe if I repair the Magneplanar speakers gathering dust in the hall. Probably worth
£400-500 on ebay... More realistically, we might be able to use slightly larger wheels and/or go down from 3/8" to 8mm chain to gear lower. Ni-cads
would be cool though...