HardWired II

[overkill]

I think that's all true as far as it goes; here are some extra points to consider:

* As you increase the contact patch and use a grippier wheel material, you need more power to spin the wheel.

* Running a smaller motor may spin your wheels, but its operating nearer its capacity and getting hotter than a larger motor. That's a key difference to the car analogy; cars have proper cooling systems while bots mostly don't.

* The time you need traction and pushing power the most is often when the opponent is wedged up on your bot, giving it more than 13Kg of down-force.

* You can increase down-force dramatically with magnets. I got an extra 10Kg with magnets weighing only 104 grams.

[razerdave]

I certainly relate to point 3: in a dead push Satanix isn't great, the ratio is a tad too low, but when I'm under something, it becomes a different ball game. Satanix 1 was a drill powered robot, only weighed 6.8kg, couldn't push jack. Then I tried it with Pain in the Asp sat on the front wedges (didn't have sharp ones at the time) and I carried him across the arena at quite a pace!

Also, there are ways to increase downforce but no up the weight, however in feathers I am not sure it's legal...

In ants, EDF fans have started becoming popular to increase the downforce on a robot significantly (The first one, FAntom, weighed in at 150g, turned on the fan, went up to 450g). It increased the power a lot as well (couldn't push a 1kg bag of flour, turns on the fan, pushes it easy). It also allows it to drive on the ceiling, just to show off :P.

Magnets are the other way, but you would need a: a significant drive system/speedo to start with to shift the excess, and a non-ferrous base plate that won't flex (Mouldy may correct me, but I think 360 or 540's base flexed out with his magnets, and also his Scorpion didn't like it.

[overkill]

That brings up another point; more pushing force also means you need an ESC with a higher current rating and batteries with more capacity. Its really tricky to get the whole drive-train balanced so everything matches with no weak points.

I noticed that the magnets on NST are mounted in little pods outside the frame, so you can definitely use that with a steel chassis. I also like the idea of using less powerful magnets to correct weight imbalances and to make a bot drive better. All my bots have too much weight over the front and less over the wheels. If I could add some magnets near the wheels, there would be more down-force where its really needed.

[razerdave]

I would have added magnet near the wheels but my whole robot is steel and my clearance is low enough already :P

I did put some in the wedges though (stainless steel base them them)

[Flag Captured]

Very interesting points about 4WD and magnets and whatnot, it's something I am considering for Hardwired II Evolution now (I'll just call it HardWired II in competition, but just to save confusion in the meantime) - it might mean that I can get that high grip by having all the weight over wheels and all that, and it'll keep the height down overall but I'd worry about being able to keep the thickness of hardox that led me to a 'skillful victory' (fluke) against a couple of spinners and just generally standing up to things. One thing's for certain, it wasn't my atrocious driving...

I think I'm going to go either Hardox brick of ultimate death if it's 2WD, or a Hardox/HDPE hybrid if it's a 4WD, moving towards the latter at the minute, given the benefits to it. Depending on cost/weight, it may have either 2 motors and timing belts for drive, or 4 motors for ultimate scary push box power. There's no reason I'd need 4 motors, but there's no reason that I wouldn't either so if it's cost effective that may be a thing...

In other news, I'm converting HardWired I to a flipper, it'll be an extremely budget setup and rebuild, just my existing TZ85s with some drills up to maybe 120-150mm wheels, so that it's invertible whether the flipper's working or not. Likewise, it'll pivot on those back wheels again like the original did, so it's totally not Maelstrom but kind of is. Well, it's that sort of idea anyway, just without that design of flipper and more like Wheely Big Cheese's. I'll post a picture of what HardWired I looks like at the minute sometime, it's basically that with bigger wheels.

Finally, HardWired III is on the backburner, I've got plenty on my plate with just these two for next year, as much as I'd love to get the spinner done, that's definitely a job for the year after - after I've proven myself a bit with HardWired II! I think I can get another year out of going weaponless, and then I'll get a nasty spinner out and get someone else to drive HardWired II, unless I win (lol) purely for a bit of variety. I like fast rambots, but I'd like to give other weapon types a shot too.
Besides, HWIII will need plenty of designing, and building - it'd be a difficult thing to get done in time with the other machines being sorted out too... I have got a few ideas for design though, I'd quite like to use a few more curved sides (Maddox's new machine, Calliope has inspired me) since I think they could stand up very nicely to spinners and whatnot, possibly even better than just straight angles. Truth be told, I'm not too sure there'll be too much of a difference (it's all just an angle still, right?), but it looks very cool whether it behaves differently or not!

Still, it's all just in the pipeline as of yet, as are my two beetleweights - just till I get Uni over and done with, then I'm going to get loads done over the summer, hopefully. Even more so if I finally manage to get a job to actually fund it all...

Plan is to have everything done at the very latest by January so I've got plenty of time to iron out creases and troubleshoot if anything does end up going wrong... I'll still be doing it at 5AM the morning before but I can dream at least haha!



Oh, and the next 'update' will have actual updates on the machines, I promise!

[mrsam]

Sounds like you have everything planned out nicely, whether everything actually goes to plan is another thing entirely. One thing i will say though, i would reconsider using wheels up to 150mm with drills, it's too much for the gearboxes to cope with so i would try to go no higher than 120mm at maximum. Other than that though i'm looking forward to seeing your flipper budget as it may be.

[Flag Captured]

It most certainly won't go to plan, but that's part of the fun!

I may look into other solutions for the drills, every time I look again at the design, it needs slightly bigger wheels... I'm sure there'll be something I can use that's cheap enough but we'll cross that bridge when it comes. If worst comes to worst, two drill motors might do the trick on either side...

The budget flipper system, not sure on specs yet - I'd like to make it FP but again I'll need to make sure I can get all the right stuff. I was chatting to Mario about it, and I think I'll be able to get what's needed - the ram might be the only piece that does raise an issue (it has to be tested first according to the rules?) but I can sort all that out. The whole thing might not have plenty of flips behind it, but I'm trying to design around getting a huge lift out of it, so it'll only need a couple of flips at the most, Wheely Big Cheese style. It'll be able to run upside down too, so it won't need it to self right and it can always double as a battering ram if it runs out of gas!

[Revsmin]

One thing i will say though, i would reconsider using wheels up to 150mm with drills, it's too much for the gearboxes to cope with so i would try to go no higher than 120mm at maximum.

Defector has 170mm wheels with GR01s, which are basically repackaged drills. Simply replace the plastic gears with metal ones, problem solved.

[Mouldy]

540's and 360s base didnt flex at all Dave- your thinking of beta- that flexed the battlebots floor- not the robot though.

Magnets in a pusher if used correctly could be a total game changer. I tried it in 540- when it worked it was a total beast… but the combination of 6wd, large wheels and a huge magnet (giving the robot an effective 40kg downforce if i remember correctly) was too much on the dewalts, i changed to speed 900's and custom gearbox's- but they failed too.

good example here;
https://www.youtube.com/watch?v=IvPACmkn41c

It drove like it was on rails, no oversteer at all, no power slides, if another pusher tried to nudge it- it may as well of been hitting the arena side wall… Magnets in a pusher could be awesome- if done correctly.

If i was to do it again id probably use 4 off RS775 banebots kits, a big magnet in the centre, square wheel base and as for tyres i wouldnt bother… id just use solid aluminium wheels with no rubber on them.

[Flag Captured]

Thanks for the insight Dave! 540 was absolutely relentless with the magnets in when it wasn't being a bit smokey! HardWired, I'm tempted to use a similar concept with less downforce, I seem to recall 540 fighting NST and it bent one of the Hardox sides in because there was no where for that energy to dissipate to since it wouldn't budge!
I do have 7mm hardox on mine and there'll be some HDPE on there too to soften the impacts some more, there's a nice enough air gap around everything, so any dents in the chassis won't really disable the robot but obviously want to avoid it as much as possible! I'll probably just trial things out between now and next year, see how it all works and try to get the optimum level of downforce and speed. Ideally, I'd like the level of speed 540 had when the motors were in (high?) gear but naturally I don't want smokey motors either, even if I am trying something new out.

It's probably the best way to put the power down though! Perhaps 40kg might be a little too much for mine, but again - definitely something I'll try out!

What sort of size was 540 too if you don't mind me asking? Looking at it on there, it looks like it was a very compact machine! Also, how did it fare against flippers? I've never seen it get flipped, it looks invertible but I'd just wonder how it would have managed without the magnets working, and what effect it had on how far the flipper threw it...

[Flag Captured]

So, I've been planning out the non-competitive disposable machines a little today, and I've got two planned (well, it's just two shells around the same set of electronics, dependent on how they last)

The acryllic version of HardWired's going to get glued up again to take on a few spinners at the next RoboChallenge event, but that won't be for ages yet so there's no rush!

The other machine/shell, made out of balsa wood (kind of want to call it Balsa Steel) will be just going to general events, probably going to make the internal structure of that shell a little more sturdy (but still out of wood) to stand up to things internally, and preserve the parts a little so I can reuse it and whatnot. It'll get absolutely battered on the outside though, which will be utterly hilarious.

Only reason I'm running these is because the drill motors I have are flat out wrecked, and are barely usable by all standards - they'll move something but definitely not a competitive machine, so instead of just chucking them away or letting them sit unused, I might as well put them in something for a laugh! It was the intention to take them down to the champs with the acrylic machine anyway, they sound like blenders and really aren't in a good way at all so what a sendoff for them!


HardWired II is coming along nicely in terms of upgrades too, me and Mario have been discussing it and it'll be a much stronger machine next year from the sounds of things!
HardWired III however... it's not really going anywhere at the minute, it's basically hinging on how HardWired II does post-upgrades, to see what sort of tech and ideas I can reuse in it. Still got a disc, and it'll still be a fast rambot on top of that (basically a 2WD Rango) but just the entire design could change pretty radically, but I'll get the sketches of that posted when I have a working computer again. I want to try and get the raw power of Combustion or Inertia XL out of it, with the (theoretical) drive power of HardWired II Evolution (post-upgrade HW2 I'm referring to as Evolution) which I know will be difficult but where there's a will, there's a way! HW2 pulled off 7mm hardox in a machine that was only 9.3 kg, so I'll still be able to add, say a 2.5kg disc, mounts and motor all in the weight limit still. If the upgrades work out well for HW2, I'll have an awful lot of push behind that disc too, so I'll be able to get some very nice engagements, but it's still debatable as to whether it'll be done for next year's champs, but it's a possibility - even if it's just as a whiteboard only machine until the year after.

And as for HardWired I, the one I'm converting to a flipper for my friend - I'm still on the hunt for suitable budget parts, looks like it can be done (I think full pressure could be done super-budget too but I don't want to push my luck) but I'm still looking for now. Just making sure everything would comply by the rules, and would be safe because I know how dangerous high-pressure pneumatics can be...

[mrsam]

Lot's of work for you over the next year or so then! As for the acrylic and wood machines i'll gladly stick both Hatchet's in with them as a kind of tag team fight, i imagine that would look fairly spectacular

[Flag Captured]

It is! I've got a year though so it'll all be fine, the two cannon fodder machines are a day's job, it's just glueing bits of it together and putting a little bit of paint on it. You're more than welcome to have a crack at at! Haz wants to let massacre have a go too, which would be rather hilarious, I think. Well, less so for whoever cleans up the arena afterwards haha

The rest of the machines will be tough work but HardWired I already has electronics made up, HardWired II just needs electrical upgrades and some extra stuff so HardWired III will really be the only machine I build entirely from scratch this year so it's not quite as difficult!

[Flag Captured]

It turns out that yesterday was precisely a year since I finished my first 'combat ready' machine (HardWired I, the huge aluminium box thing) and just look how far it's come in a year!

Would just like to say a huge thanks to absolutely everyone who's helped out, I really appreciate it all and it's allowed me to finally take part in combat robotics, which is something I've been wanting to do since I was 2 which is awesome, frankly! Aside from that, it's actually tempted me to switch into doing engineering at university. Not entirely sure yet, going to see how I do with my media course first (and when I inevitably fail) but that's something!


Onto the updates (or lack of, as is always the case) I've been looking at some ideas as to what I can do with HardWired III, I'm still looking at a spinning disc, but I'm not sure how to design it - I'd like something small-ish in diameter with high KE, so definitely single tooth. Part of me wants to have it some crazy thickness so it'll be quite heavy, but I'm not entirely sure.
Basic plan is to essentially have it the same design as HardWired II with some dimension changes, so it handles a disc better and works around a bulkhead construction. Unlike HardWired II though, I'm going to make this machine (as far as I can) on my own, purely as a technical exercise to try and boost my own skills - not that I don't want to work with anyone on robots, just if I can drop myself in at the deep end, I'll be able to fix my machines instead of looking at it with a cup of tea in my hand saying "it's broke tha' 'as". I know the basics already, but it can't harm!

Not sure what to go for yet though, I want to have it built for next year's champs (probably be a whiteboard machine, depending on how things go) but the materials I'd need would be quite expensive I'm led to believe, and if they're not then the cutting for them will be - primarily, the bulkheads I'm on about. Kinda want to use Alumec or something for it, but I think that's quite expensive. Same could be said of the original plan, which was to use 15mm-ish Hardox. Hardox solves all the problems.

Definitely going to use some kind of non-magnetic steel for the base though, since I'm going to be using magnets to compliment the brushless drive I'm planning to use. Take Rango and 540, mix it with a little bit of Inertia XL and that's kind of the idea I'm going for. I do have some sketches on my old laptop, but that's dead.

Problem I'm going to have is it self-righting and also fitting everything in the machine, so again there will be some Cad-ing to be done if I can learn how to CAD properly! I'll probably keep HardWired III at 6-7mm ish Hardox but only in key places (around the motors etc) so that they don't get damaged, other than that it'll be 3mm and HDPE. Basically building on HardWired II's strengths, in other words. H2 will remain just a pushy box of death though, and I intend to make it super reliable, or at least as much as I can!

[razerdave]

Non magnetic steel. That'll be stainless steel.