Tormenta 2 - Build Diary

[archie2000]

oops cheers haz.
looks good for sketchup i can't do that

[Ellis]

The CAD has actually changed some since I (a little foolishly I now know) uploaded loads of pictures. Main change is to the front, in that the shaft is now in the middle of the robot (up and down wise) and so the shape of the theoretical scoop has changed. 'Top' lifter has too. Oh and the front drive motors have been moved back 25mm.

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Day 1 of the actual build has come and gone! We made very good progress in the few hours we were out there. So incredibly hot (I currently have a serious headache) that we took quite frequent breaks but still, things went very well.

We managed to get the bulkheads well on the way, got the back armour cut and made the main shapes of the four drive motor mounts. Currently our only precision let-down has been the back armour which is a piece of black HDPE 90mm OD piping cut in half, and as it comes on a reel the piece we got was madly bent. We have managed to get it close to straight, and we will do eventually, but it's not great.

Otherwise, everything went disturbingly smoothly. I am fully aware that we will pay in one way or another down the line (I have no idea how we'll get this thing in weight) so hopefully I won't jinx it by knowing that!

Anyway, pics of today's progress - http://s1088.photobucket.com/albums/i32 ... menta 2/

[harry hills]

looks great man, think you're on to a winner.

you solve the problem of it being bloody massive yet? or did you just do the sensible thing and ignore it?

[Ellis]

Ignored it and actually made it bigger still.

Thanks.

[Ellis]

Second day has gone well. Back motors are ready to be permanently mounted, and the front ones are close. The front motors in the pics are not the final ones. We have to buy some fresh, as the poor things (as you can see) in the pics are pretty ratty now. Believe they were once NST's drive motors, so they must have given a couple years worth of use. We still have them as spares.

Tomorrow we intend to join everything built so far together. Going to be interesting, as the system we are going to use is a barrel-nut-and-bolt style... thing. Having tried it on some test pieces, accuracy is crucial. Accuracy we don't really have.

Oh well, we shall find out, I am sure. Pics of today's work: http://s1088.photobucket.com/albums/i32 ... menta 2/

Must say I am/we are quite proud of those motor mounts. Neat and light and strong yet flexible. Good.

[Ellis]

We got the new drills yesterday and I got them into shape for use over the course of today. In the process I made this video, if anyone is interested:

Having prepped both, my dad and I managed to get some time in. All four motors are now mounted (not permanently but the setup is complete) and we mated the two bulkheads with the baseplate. Miraculously, it sits level. Really level. We both simply stared at it when we first put it on something flat. Right on target at 3-4mm!

Pics fresh from the oven: http://s1088.photobucket.com/albums/i32 ... menta 2/

If we get some time, tomorrow could well be test day. We charged the batteries tonight in preparation. Since this one is low to the ground (unlike Tormenta's 10mm), we're not sure where to test it. Perhaps the local sports centre?

And if anyone is interested, it weighs in the region of 5kgs at this point. 3.2kg of that is in the motors, their mounts, and the wheels.

[Ellis]

We have done a good bit of the wiring, and jeez this thing is small inside! Actually quite worrying, there won't be any free space at all!

Since we have the right batteries and it weighs just over 5kgs, it goes like an absolute bat out of hell. It's almost silly. It wheel spins for almost 2 seconds as it is. Might try and get a video but the wiring is all over the place and, bringing me to my two points:

The motors got hot (any more and it would be uncomfortable to hold a hand on one) after just a minute or two of feathering the throttle, with a full blast or two here and there, around the living room. Could they be getting hot because, being at relatively low rpm as I was being light on the throttle, the motors are getting full power (some 20vs) but the fans aren't doing anything? By that logic, driving faster would result in less heat? Is that possible?

And secondly, the Electronize are all over the place in control, really. Fine for Tormenta but we'll be limiting the drive of v2 if we stick to them. Would people advise for or against getting two of the 25a BotBitz controllers? They come to similar money as a single new 30a Electronize which is what we need for the lifter, so..

Thanks.

[Mouldy]

Being the fastest isnt always a good thing....

With some tx's you can limit the throttle to a set percentage - basically setting it so it never goes above a certain voltage...

on my dx7 i have a 3 position toggle switch thats assigned for limiting the throttle in diablo...all the way back is high speed, middle position is about 80% and the last position is about 50%.

My first combat test of the botbitz esc's will be on sunday, ill let you know how they do, but all the aussies are using them now with no troubles. Theres a video of diablo driving around on my youtube page that might help you decide.

[archie2000]

sounds good there Ellis
when your electronics are really compact either tape or heat sink the wires. i shorted hazard2 about 2/3 times i. think mostly because of. the wiring.
and 20v dosent sound good with drills

[Ellis]

Thanks guys. Yeah we're being very careful with the internals: heatshrink on everything, nothing will be longer than it has to be, etc. Also making sure not one bit of the system can limit power. From the output of the batteries to the motor terminals everything is rated 30amps-able or above. Result is it screams. As for 20v, we have the 18v packs but fully charged they're around 20v. We ran the setup in Tormenta for 7 battles without an issue. Fingers crossed.

@Dave, we had considered limiting the voltage via the tx once or twice but found ourselves wondering why. It'll be battling for an absolute max of 3 minutes, I like to think the motors will handle that time, especially since most of it will be near full throttle and the fans should work. Plus, we're using the functional but simple Planet 5, which doesn't have any fancy limits built in.

I saw the video of Diablo on your channel, but you were running the 85a model, right? You say you'll be testing the Botbitz on Sunday, you mean the 25a or 85a ones?

Thanks.