Search found 185 matches

by MarkR
Fri May 17, 2019 4:53 pm
Forum: Antweights
Topic: Malenki-ESC open source Antweight ESC
Replies: 18
Views: 703

Re: Malenki-ESC open source Antweight ESC

http://vectrex.org.uk/mark/malenki-kicad.png http://vectrex.org.uk/mark/malenki-irl.jpg Parts are here, I have made a couple of the boards so far. It all seems to approximately work, the firmware at least drives my test robot around. If anyone wants one, please PM me, I can make up about 9ish board...
by MarkR
Wed May 08, 2019 10:09 am
Forum: Antweights
Topic: Follow up on Digital CR Servo Board ESCs
Replies: 13
Views: 258

Re: Follow up on Digital CR Servo Board ESCs

All the dead-band logic is inside the MCU, so good luck tuning it. These tiny little MCUs have their own free-running oscillator which goes at whatever speed it feels like. So the MCU might be nominally clocked at 1 Mhz, but in practice it's 1 Mhz +- 10% or maybe worse than that. So the firmware mig...
by MarkR
Wed May 08, 2019 9:01 am
Forum: Antweights
Topic: Follow up on Digital CR Servo Board ESCs
Replies: 13
Views: 258

Re: Follow up on Digital CR Servo Board ESCs

Good detective work. The AM1096 is a very interesting chip because it's a motor driver with built-in voltage regulator, so it saves them components on the board, the LDO voltage regulator presumably supplies the microcontroller, which makes it a "true" 2-chip solution which can handle a wide range o...
by MarkR
Tue May 07, 2019 4:08 pm
Forum: Antweights
Topic: Follow up on Digital CR Servo Board ESCs
Replies: 13
Views: 258

Re: Follow up on Digital CR Servo Board ESCs

Ok, I didn't realise there were two chips. Probably one is a cheapo no-info Chinese Microcontroller, the other is a motor driver, similar to the MX612. Actually the MX612 has pins 5,8 connected to the motor. Don't run it off more than 10V, it's outside of its spec. I actually bought some MX612s, but...
by MarkR
Tue May 07, 2019 2:57 pm
Forum: Antweights
Topic: Follow up on Digital CR Servo Board ESCs
Replies: 13
Views: 258

Re: Follow up on Digital CR Servo Board ESCs

That is very interesting.

Did you, by any chance, get a part number from the 8-pin chip on the blue ESC board above? The Dorman servo board? Is that the only active part on the board, or is there a small transistor too?

Mark
by MarkR
Thu May 02, 2019 12:19 pm
Forum: Questions (and answers)
Topic: 5V bec?
Replies: 6
Views: 137

Re: 5V bec?

Don't most speed controllers have one built-in?

I know the Dasmikro has one, also some brushless esc.
by MarkR
Wed May 01, 2019 3:17 pm
Forum: Antweights
Topic: Tiny 6mm gear motors appearing in Aliexpress
Replies: 2
Views: 109

Tiny 6mm gear motors appearing in Aliexpress

Hi, Has anyone tried these motors? https://www.aliexpress.com/wholesale?catId=0&initiative_id=AS_20190501071600&SearchText=gear+motor+6mm They are getting quite cheap and super, super tiny, maybe good for fleaweights or antweight? Would the (plastic) gearbox destroy itself instantly if we put 8v thr...
by MarkR
Fri Apr 26, 2019 9:01 am
Forum: Antweights
Topic: The Hotel Lima, for Ants: A Build Diary
Replies: 93
Views: 3169

Re: A Hotel, constructed of Limas, for Ants: A Build Diary

It's easy to preach after the fact... I usually test my electronics with a multimeter (for short circuit) bench supply (for functionality) before plugging a lipo in. The Lipos give enough current to pop the magic smoke out of any faulty electronics. That said, I've never had the lipo itself catch fi...
by MarkR
Mon Apr 15, 2019 8:00 am
Forum: Questions (and answers)
Topic: Small ESCs outside the UK
Replies: 13
Views: 469

Re: Small ESCs outside the UK

George- I will try enabling braking to see what happens. I didn't realise that braking was a useful feature, I didn't use braking on my previous robot (Betsie, which has a sort of fly-by-wire system anyway) and I've not implemented braking yet in the new speed controller (but the hardware is capable)
by MarkR
Mon Apr 15, 2019 7:53 am
Forum: Antweights
Topic: Pre modded servo boards for escs?
Replies: 30
Views: 924

Re: Pre modded servo boards for escs?

Sounds more like a poor design or poor choices of parts, than a manufacturing defect. A voltage drop of 2V at the kind of current we'd see through a N20 is extremely high, did you have access to an oscilloscope? Maybe the duty cycle is less than 100% even when the stick is at the extreme position? -...
by MarkR
Mon Apr 15, 2019 7:48 am
Forum: Antweights
Topic: Malenki-ESC open source Antweight ESC
Replies: 18
Views: 703

Re: Malenki-ESC open source Antweight ESC

Sounds like there is enough interest for me to knock up a batch. I'll let you know when they're ready and we can sort out the details (it will not be really soon, I need to order more parts, the boards are in the post).

There are also a few more tweaks to the firmware that I'd like to do.
by MarkR
Sat Apr 13, 2019 10:40 pm
Forum: Antweights
Topic: Malenki-ESC open source Antweight ESC
Replies: 18
Views: 703

Re: Malenki-ESC open source Antweight ESC

Do you have a link to the datasheet?
by MarkR
Sat Apr 13, 2019 10:14 pm
Forum: Antweights
Topic: Malenki-ESC open source Antweight ESC
Replies: 18
Views: 703

Re: Malenki-ESC open source Antweight ESC

Hi, It seems the Malenki-ESC is now working a lot better. * It does bot :) - I've built part of my next bot and it's driving just fine with 2 N20s. * I solved the voltage regulation problem which caused 2 mcus to be destroyed If I make a *small* number of these boards, does anyone want to test one? ...
by MarkR
Wed Apr 10, 2019 1:54 pm
Forum: Antweights
Topic: DVD-RW motor?
Replies: 1
Views: 94

Re: DVD-RW motor?

It is probably a brushless motor. I'm fairly sure that the 4th wire is a centre-point wire in the Y configuration of the brushless. It could be difficult to identify the wires. I suggest something like this: * Measure the resistance between each pair of wires * The one with the lower resistance to t...
by MarkR
Tue Apr 09, 2019 4:21 pm
Forum: Antweights
Topic: The Hotel Lima, for Ants: A Build Diary
Replies: 93
Views: 3169

Re: A Hotel, constructed of Limas, for Ants: A Build Diary

I wasn't suggesting removing the protective film from the pack, just the warning label on the lead :) I did peel the labels off one of my packs because I was trying to fit it into a very slim space (actually rather stupidly, I bought larger packs than necessary, 300mAh). But not the film or anything...