Help? - Wireless Control for a Servo Motor

Projects
1

Hi,

Can anyone please help build a WiFi switch for a servo motor? Willing to pay for this! :slight_smile:

Use case: The servo motor will turn 180 degrees as long as the wireless button is pressed. When the wireless button is released, the servo will go back to its original position.

This setup seems to be exactly what I need, but the transmitter is way to big, it’s for RC Cars/planes This receiver seems to be perfect - https://www.youtube.com/watch?v=qh9WkWXM_1g

Would want to have a simpler switch, just on an off, much like this one

Thanks so very much!

Gabi

2

Hi why not pop down on a Thursday evening (Electronics night ) I’m sure someone can help you out or point you In the right direction , Brian D=

3

Which bit needs to be wireless, the servo, the button or both? Is latency between the button being pressed and it moving important? Does it need to be wifi, or could it be something else?

4

@platinumnqueen22, Thanks! Could come by this Thursday, but I’m afraid it will just be too hectic - I want this to be quick and clean haha! :slight_smile:

@naxxfish,

  1. Thanks for the reply!
  2. Both the button and the servo needs to be wireless. Latency is not a problem.
  3. The distance between parts is always less than 3m - it could probably be Bluetooth or WiFi, doesn’t matter.
  4. It’s for a prototype - so it’s acceptable if the reliability is not 100% but it needs to be smallish (ideally not more than 5x5x5cm)
5

Well. If it doesn’t have to be IP, that’ll make things simpler (you won’t need a wifi network, for a start).

Here’s a quick solution:

A remote button kit which toggle a GPIO relay when the button is pressed:

https://www.rfsolutions.co.uk/remote-control-systems-c9/hornetpro-1-channel-150m-868mhz-12-32vdc-system-p714

Then a servo controller to set the position of a servo when a TTL level signal is recieved

Configure the servo driver first using USB to set the servo to the right position when you get a 5V signal, hook it up to the receiver’s output

EDIT: found a cheaper wireless button kit:
https://www.amazon.co.uk/dp/B073ZCW7P4/ref=asc_df_B073ZCW7P452470250/?tag=googshopuk-21&creative=22146&creativeASIN=B073ZCW7P4&linkCode=df0&hvadid=214190284008&hvpos=2o4&hvnetw=g&hvrand=11120152677717718920&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9044970&hvtargid=pla-424003658398

6

@naxxfish, this is actually such a great idea! Thanks!

I’v already bought this button which works and looks good, but I didn’t know how to properly connect a servo to it.

Will order the Controller; if I can’t manage to get it to work, would you please give more directions? :slight_smile:

7

Ah well, that’s handy!

Yeah, get the Pololu controller - it’s pretty straightforward. More details here:


They’re pretty decent little things!

Here’s how to wire up the switch (see Button or switch) - NB you’ll want to hook up positive and negative to your relay terminals so you don’t need a pullup/down resistor)

Then, with it connected to your PC with USB, configure it in the software:

Then create a script to control the servo based on the input (see Using an analog input to control servos )

That should be about it really!

8

Chris, you’re a legend! I owe some beers now!

  1. Just ordered the part and will try what you suggested, tomorrow.
  2. Is there any chance to make the receiver even smaller? The receiver from my switch coupled with the Maestro Servo Controller gets to double the size of what would be ideal.
  • Do you know if we can find a significantly smaller controller?
  • Do you think we can find or make a simple and small switch to work with this receiver?

Again, thanks so much, your help is highly appreciated!

9

No worries !

Depends on how much time you want to invest, but you can get the 433Mhz OOK Rx modules on their own and they’re pretty small , but you would need to design a microcontroller board to do the coding/decoding. The advantage there is that you can control the servo directly from the microcontroller and eliminate that step.

Or go the other direction and build a transmitter that sends DSM2 to an off the shelf RC reciever like the one you linked to. I think that’s likely to be more complicated !