Topics tagged with servo

Controlling servos without the pwm expansion board

Lazar Demin — Thu, 09 Jul 2020 22:18:42 GMT

@josheanes9 http://docs.onion.io/omega2-docs/generating-pwm-signals.html

Micro Servo Jitter

OnioneerX — Thu, 25 Jul 2019 20:43:56 GMT

Hi, I followed the tutorial about controlling servo motors with the expansion, I'm using a Tower Pro SG90 Micro Servo and I noticed it frequently has weird ticks or random movements.

I wonder if this is because of this particular motor or if it's something that happens with all servo motors?

PWM board related

György Farkas — Sun, 15 Apr 2018 22:00:31 GMT

@ccs-hello said in PWM board related: OP is talking about driving motor(s), not LED Yes. Please notice only OP wants to connect a motor to the PWM Expansion - not me. (sink 25 mA max per channel.) 400 mA in all! It's not bad for this degraded "signalling-only" board. What motor can be driven only using 25 mA? Who knows? I'd be curious too. See also the first paragraph of PWM Expansion Back EMF, stall current, etc.??? Motor driver board is the way. flywheel diode, snubber, no-load current, ... A logic level n-channel MOSFET (or an NPN transistor) and a 1N400x diode are not enough - all we need is motor driver board!

PWM Expansion Crashes Onion2

Andrew Moore — Sat, 10 Mar 2018 17:33:28 GMT

[SOLVED] I found out the servo is discontinued. I think it has flaws in its design. I can't explain why it sort of works (only one direction) from the USB thing and does not from the expansion board, but I got 2 different newer winch servos and they work great in both directions from Onion and my USB thing, so it has to be a faulty servo. I have a feeling it had a 1 to 3 turn limit before breaking a cog if it driven past that, then once the cog is broken the pot doesn't return the right values and its all screwed up. Anyway the expansion board seems pretty bullet proof for noise and EMI EMF, I man handled it pretty good.

Omega2 PWM-Expansion and Node.js

Gyula Matics — Fri, 26 Jan 2018 12:05:02 GMT

I know this is an old topic, but I hope this will be useful to somebody. It would have saved me a couple of hours. Apparently the setupDriver, setFrequency and disableChip methods require a callback to function correctly. pwmExp.setupDriver(0,50,0, () => { console.log("setupDriver success."); });

Servo Expansion Questions (How many...)

Gabriel Ongpauco — Thu, 19 May 2016 23:20:47 GMT

Hi @TheMonkey-King, The 16 PWM signals means that you can run up to 16 separate servos, but you would need an external 5V power supply with enough current to supply all of them. The Omega by itself can power 1 or 2 small servos under very light load, although it can get a standard size servo to turn a door lock here! You would definitely need to find the maximum current draw of each servo (usually in their specs), and make sure your external power supply can provide more than the sum of all maximum currents (for safety). Labelling each wire is very handy, you can either label by part/location or by #; the connectors on the Expansion are marked from S0 to S15. Full technical details are available in our Servo Expansion Tutorial. PS: Please post your project when you're done, we'd love to see it! Gabe

A newbie that needs help

Boken Lin — Tue, 01 Dec 2015 17:58:42 GMT

@Leonard-Stroman That makes it much easier. Code written in Python don't need to be compiled because it is an interpreted language. You simply need to install python on the Omega, copy the code over to the Omega, and it should be able to run. The only thing you will need to wait for is our python wrapper for the PWM expansion driver. We should be releasing that in the next couple of weeks.

Using fast-gpio with the servo expansion

Lazar Demin — Wed, 11 Nov 2015 18:15:50 GMT

@Rob--Marston There's a Servo Expansion application available on the command line: pwm-exp Check out this help desk article for a full guide