ESC for Dalek

[Anttazz]

Currently using a BotBitz 25a ESC on the Dalek but don't fully trust that it'll be able to handle such a big motor for long.so looking for something that'll be able to handle it without stressing itself. Only 1 channel required and it's using a mobility scooter as a sense of scale required.

Cheers.

[typhoon_driver]

Get an 85a turnigy?

[Anttazz]

They're only 30A for 3 minutes and the Dalek is easy over 100kgs and gets fairly warm so not too sure it'd last. The 25A one is seriously hot after 30 seconds or so

[typhoon_driver]

ok silly question time, if you are inside the dalek then why not just have a manually actuated relay inside? Simple on/off control.

[Anttazz]

The person controlling movement probably won't be inside, you can't really see out and theres loads of buttons and switches to press as it is. Plan is that at some point we could put an actuator on the front wheel and control the whole drive remotely if we don't require lights/sound/arm control. Its a weird setup but quite fun.

[craig_colliass]

As mentioned before I use the Sabertooth 25A in Pilgrim the weight is at least 60kg never had a problem, but it is slower than a Dalek.

That's a sentence I thought I would never write!!

I would perhaps put forward the use of a Victor 833 I think the range is about 60A and is fan cooled! I use one in the lifter in Cherub and seems fine.

A few questions
what is the specification of the motor, drive ratio ,wheel diameter calculated speed? do you use the acceleration ramp on the speed controller? is it over volted?

[typhoon_driver]

I would focus your efforts on removing the person inside. That will remove around 80kg give or take from the weight of the machine which would allow you to use a smaller speed controller. Shouldn't be too difficult to put a large servo in there capable of shifting the steering and then a second tx to control the voice module.

[Anttazz]

I'll have a Pilgrim vs Dalek race at our event in a few weeks Craig and see who's quicker

I'd forgotten about Victors, i'll see if there are any of them around and give that a try.

As for specs, i'm guessing a bit as I can't find the exact model's spec sheet but the general consensus seems to be that its a 750w motor at 12v on 8" tyres and supposedly hits 5mph. The controller is running pretty much the way it was out of the Scot-Bot kit but doesn't seem to have ramping on it.

Making the drive RC would be easy, but fully automating it would be a nightmare. Both arms move on 3 axis and have one that fires water, 40 button lighting controls that can only be used inside the Dalek (IR) and the voice unit is a modulator rather than recorded sounds so needs someone to speak into it.

[craig_colliass]

750W motor that is quite powerful with only 12 volts to it!! My reckoning that's over 60A. with a top end of 5 mph I don't think the Victor 833 will have a problem. If the Dalek is run on dry cell you could drop the volts a little, But I would try the victor.

[blazerbotics]

just throw a 4QD in it.

[teamstorm]

I have a 4QD NCC-70 going spare. Would be perfect for you, just attach a pot to a lever and you've got a speed control handle, and at a later date you can connect via an interface to an RX if you want.

Detail here - http://www.4qd.co.uk/prod/nccMk2.html

Un-used, yours for £50 !

[Anttazz]

I could be looking at the wrong spec sheet, but I think thats what it said. Its a massive motor though so its maybe right. It runs off of a car battery, so can't really change the voltage.

I have one of the smaller versions of the ones you're talking about Ed the NCC-35. I'll maybe wire that up and see how I feel about the drive being on the inside and if its all good i'll be in touch