Search found 125 matches

by MarkR
Wed Jan 16, 2019 8:21 am
Forum: Antweights
Topic: Pi and voltage regulator fail - overheat?
Replies: 2
Views: 54

Re: Pi and voltage regulator fail - overheat?

I have connected capacitors. Considering the situation again, it seems possible that the regulator has developed a fault caused by an earlier overheat condition. I have some spares so I will replace and test it today to check that it can give stable 5v. The problem I have with Antweight electronics ...
by MarkR
Tue Jan 15, 2019 9:31 pm
Forum: Antweights
Topic: Pi and voltage regulator fail - overheat?
Replies: 2
Views: 54

Pi and voltage regulator fail - overheat?

I thought it was all working. I have a Raspberry Pi Zero - this draws about 100-200mA I built a custom power supply / regulator board which also controls the flipper weapon. I used a "Chinese special" KIA1117-5.0 voltage regulator ( see https://datasheet.lcsc.com/szlcsc/KIA-Semicon-Tech-KIA1117-5-0_...
by MarkR
Mon Jan 14, 2019 6:32 pm
Forum: Antweights
Topic: Using brushed Motors for gripper or hammer weapons
Replies: 6
Views: 230

Re: Using brushed Motors for gripper or hammer weapons

I don't think you'll run down batteries much with a single N20. In my experiments, the stall current running on a 2S pack is about 800mA (at least on the cheapy motors I have, the polulu high power ones probably much more). As I run 300mAh packs, 800mA will take longer than a 3 minute fight to have ...
by MarkR
Wed Jan 09, 2019 4:15 pm
Forum: Antweights
Topic: Using brushed Motors for gripper or hammer weapons
Replies: 6
Views: 230

Re: Using brushed Motors for gripper or hammer weapons

I used one for a flipper weapon, and DerekDudge used one for a hammer weapon (Manticore) you can see in the video from the AWS55 event (It looked great and got a lot of applause but not terribly effective) I think it depends on the gearbox ratio, but the 100:1 that I used are safe to stall for a whi...
by MarkR
Wed Jan 09, 2019 8:21 am
Forum: Events
Topic: Bugglebots
Replies: 1
Views: 81

Re: Bugglebots

I am really enjoying Bugglebots. I think that Beetleweight is a really good class now (watching Bugglebots). It seems that there is a good variety of designs and a range of different builders, I imagine that they're not too expensive to build or transport (e.g. don't need to hire a van etc). As I un...
by MarkR
Fri Jan 04, 2019 6:27 pm
Forum: Antweights
Topic: SG90's at high voltage
Replies: 4
Views: 116

Re: SG90's at high voltage

Looking at the spec of the SG90, it looks like the gearbox is a crock of sausage, so it's not going to last very long if the motor gets overvolted. I have some of those continuous servos which I used on an earlier (non-combat) robot at 5v, they are poss weak (but very easy to control from a gpio on ...
by MarkR
Fri Jan 04, 2019 3:02 pm
Forum: Antweights
Topic: SG90's at high voltage
Replies: 4
Views: 116

Re: SG90's at high voltage

I run my flipper N20 motor at about 17v. It hasn't burned out yet, but I run it at a low duty cycle controlled by the microcontroller, so the driver can't just hold the stick to maximum. I am more worried about the gearbox than the motor, I think the metal gears might fail eventually (testing this m...
by MarkR
Tue Jan 01, 2019 5:39 pm
Forum: Questions (and answers)
Topic: Armour /chassis material
Replies: 1
Views: 171

Re: Armour /chassis material

About connecting - I use M2 nuts and bolts and they're awful, don't do that :) If you want to use nuts and bolts, use at least M2.5. Nylon nuts & bolts are weak but easily replaced and bolts cut to length. Steel bolts are harder to cut down to size (I use a belt sander, it's really tricky to do beca...
by MarkR
Tue Dec 11, 2018 10:28 am
Forum: Antweights
Topic: Team Antiquarian build diary
Replies: 30
Views: 1782

Re: Team Antiquarian build diary

Yes the datasheet does specify a 470uF electrolytic, so technically there should be two (one for each channel) but in my design I just used a surface mount 47uF and it seems to do the job - at least, it smooths the spikes enough so it doesn't cause the processor to reset every time I trigger the fli...
by MarkR
Tue Dec 11, 2018 10:25 am
Forum: Antweights
Topic: Team Antiquarian build diary
Replies: 30
Views: 1782

Re: Team Antiquarian build diary

That looks like a robust ESC, it's a shame the holes are too small for your wires. (I hate wires soldered to pads, it probably wrecked my Dasmikro and many others' too) The TA6586 seems literally exactly the same part as the RZ7899 I'm using, except it is a pin-through-hole DIP version. I use the su...
by MarkR
Mon Dec 10, 2018 9:14 pm
Forum: Antweights
Topic: Team Antiquarian build diary
Replies: 30
Views: 1782

Re: Team Antiquarian build diary

It looks great, but I wonder, what is the purpose of the large electrolytic capacitor? Is it really required, or can you maybe use a smaller one?

Mark
by MarkR
Wed Dec 05, 2018 11:31 am
Forum: Questions (and answers)
Topic: Is this right?
Replies: 3
Views: 389

Re: Is this right?

When I was using a Dasmikro with my Raspberry Pi, I discovered that both signal wires (left & right, or drive and steer) need to be sending pulses, otherwise the Dasmikro won't turn either motor. So I think you need both signal wires connected, even if you're only using one motor and the "no mixing"...
by MarkR
Wed Nov 28, 2018 12:07 pm
Forum: Questions (and answers)
Topic: Cleaning gear motors
Replies: 4
Views: 247

Re: Cleaning gear motors

How does an ultrasonic cleaner remove shavings of brass? Does it just unstick them so they can fall out more easily?
by MarkR
Mon Nov 26, 2018 4:37 pm
Forum: Questions (and answers)
Topic: Lights on a robot
Replies: 2
Views: 164

Re: Lights on a robot

No, it's optional but fun.

Some RXs or speed controllers have indicator LEDs, other builders add their own.

There was one robot at AWS56 - the one controlled by a MicroBit - had an amazing amount of bright LEDs, perhaps to blind the opponent? :)
by MarkR
Fri Nov 23, 2018 11:05 am
Forum: Antweights
Topic: "Flip-it” new build/project
Replies: 73
Views: 5930

Re: "Flip-it” new build/project

It looks like the RadioHead library has its own set of protocols which are not necessarily compatible with anything else. I don't see any mention of standard RC protocols in there (e.g. the dsm2 and dsmx or flysky protocols?) But that's ok if it works for you. I'm looking at how to build a receiver ...