Featherweight Speedos

[big_nipper]

One is now in Little spinner as of last weekend, but has not been to an event using it, allthough we are taking it to an event in 2 weeks just to test the drive.

We have fitted 2 heatsinks to it though, one for the mosfets and one for the voltage regulator which gets very hot with a battery voltage around 28V and using the BEC.

Still need to do some work on it as the Spectrum sometimes enters failsafe when we turn the spinner on, even with a 0.5 seconds slow turn on. I assume this is due to a combination of the BEC in the Scorpion XL and not much storage capacitance, but will look into it as there seems to be alot of noise on the 5V line.

[leorcc]

Thanks for the info Mark. The nipper team is going to be at XFM with it?

[woody]

Mark ... Are you aware of the recent mods to the XL?

http://forums.delphiforums.com/THERFL/messages?msg=2640.18http://forums.delphiforums.com/THERF...es?msg=2640.18

[big_nipper]

Thanks woody, but we should have the new versions as they work with the spectrums just not when the weapon is on, but will check the voltage regulator at the weekend.

Leo, Yes

(Message edited by big_nipper on May 24, 2007)

[jamesb]

having spoken to Mark it sems the huge current draw of the magmotor is causing the voltage to drop suddenly from 28v to 3v for a fraction of a second. This triggers the scorpions on board failsafe.
Mark is working to fix this, and a seperate reciever battery may cure it.
This may be the same thing that was happening to Cyberon at Northampton last weekend.
All scorpions supplied through me have the updates mentioned by Woody, so should work fine with the Spektrum.

I will just use this thread instead of making a new one.

My dad is about to start making his robot and is wondering what speed controllers to use.

He is using 4, 18v drills and we were told by robot power that the scorpion XL would not handle them. Would running 2 scorpions be ok?

if not what speed controllers would be the best option?

Also my dad has just asked me what would be the most powerful drive, 4, 18v drills or 2 gold motors?


Will

[leorcc]

Is it going to be a pushbot? Go for the Sidewinder. with 4 18V drills or 2 24V gold motors youll be thankfull you did.

[RogueTwoRobots]

Drills vs Golds - Personally Id go for golds if you can afford the cost of them, the drive train, and batteries to supply them with enough oomph.

Obviously the drills come with the whole gearbox attachment so its just a case of bolting them to a chassis, but with golds you have much more flexibility over desired speed and pushing power. One particular example that sticks in my mind is Team Mads Omega. If youve seen that in action youll know its a more-than-able pushbot (its on a 3.4:1 reduction I believe).

I think Omega also uses 15A microprocessor Electronizes for control (is that correct Alan?) so that controller or anything above in terms of rating should be sufficient to control them. The extra costs of the drive-train and motors is kinda balanced out by the possible use of low-cost speedos

[grant_ploughbot]

I would go with the drills as the gold motors are pretty heavy, and 4 drills should be more powerfull and much easier to create 4wd/easier to get hold of and cheaper.

[geeza]

Will you should have noticed by now that Whirlpool can out puch DB5. So drills win, but I think that my drive is now more reliable than drill gearboxes.