Transmission of PWM signal not working.

In summary, the individual is working on a project to control a cheap commercial Quad-copter using EMG instead of a remote. They have successfully set up the EMG with an Arduino, but are having issues sending the data to the quadcopter. They have replaced the potentiometers with wiring that goes to Arduino PWM out pins, but the controller is resetting when activated. The individual believes this could be due to the PWM signals needing to be converted to 0-3V analog and suggests using a single pole RC filter and a voltage divider with a capacitor to improve response.
  • #1
FraserI
1
0
Hey guys,
So I'm working on a project currently being built off of a cheap commercial Quad-copter (Syma X1) as it's base platform. Just as a little background I am trying to make it so that it is not controlled by a remote (that is pushing knobs and levers up and down to control it) but by EMG. I have the EMG stuff all setup and working nicely with an Arduino, but I am having issues sending the data to the quadcopter.

Before I tore the remote apart it used simple potentiometers to alter a voltage (0-3v) which was then sent to a transmitter and sent off to the quadcopter where it was received and you were able to fly the thing. What I've done is removed the potentiometers and replaced them with some wiring that goes to Arduino PWM Out Pins. I then have my input coming into the Arduino via analog in pins, it goes through a mapping filter i wrote to get it to the correct voltage values and then they are sent to the PWM out pins. When I start activating the controller (flexing, causing it to change the voltage) the board sort of freaks out and resets.

I have no idea why this is and need your help! I have a few ideas... The transmitter is unable to send PWM signals? and it simply sees a huge voltage spike from 0 to 5v when i do anything as opposed to averaging based on whatever the duty cycle is OR there is some issue between the Arduino which has its own power supply and the controller which also has a power supply (when i try and ground them together the controller freaks out and tries to reset). Any help would be hugely appreciated!

jg8eZsm.jpg
 
Engineering news on Phys.org
  • #2
I bet the Pwm needs to be converted to 0-3V analog.

It sounds like the controller sends analog signals somehow (I don't know your controller/receiver/servo method) not data.

Conversion can be as simple as a single pole rc filter.
 
  • #3
It seems like you have 4 of the PWM outputs from the Arduino connected to the remote board but no common. You will need to have a return path for current from the remote board to the Arduino. There should be no problem connecting the grounds of these two systems. Scaling could definitely cause problems with the 3V system receiving 5V signals. Also, since you don't know the frequency response of the remote voltage inputs, you should put a filter on the PWM to "convert" it to an analog voltage. A simple RC network on each PWM output should make some improvements. I would suggest a voltage divider that will limit the output voltage to 3V with a capacitor across the 3V output. Size the capacitor by calculating the time constant that will give you reasonable response of the remote (50ms should be decent).
 

Related to Transmission of PWM signal not working.

What is PWM signal transmission?

PWM (Pulse Width Modulation) signal transmission is a method of encoding information on a signal by varying the duty cycle, or the ratio of time that the signal is high to the time that it is low. This method is commonly used in electronic systems to control the speed of motors, the intensity of LEDs, and other devices.

Why is my PWM signal not working?

There could be several reasons why your PWM signal is not working. Some common causes include incorrect wiring, faulty components, incorrect programming or settings, or interference from other electronic devices. It is important to troubleshoot and identify the specific issue in order to fix the problem.

How can I troubleshoot my PWM signal transmission?

To troubleshoot your PWM signal transmission, you can start by checking all of your wiring connections and making sure they are correct and secure. You can also test your components individually to make sure they are functioning properly. Additionally, you can adjust your programming or settings to ensure they are correct for your specific application.

How can I improve the transmission of my PWM signal?

If you are experiencing issues with the transmission of your PWM signal, there are a few steps you can take to improve it. These include using shielded cables to reduce interference, adjusting the signal frequency to avoid any interference from other electronic devices, and using a stronger power supply to ensure a stable signal.

Are there any common mistakes that can cause PWM signal transmission failure?

Yes, there are a few common mistakes that can cause PWM signal transmission failure. These include incorrect wiring or connections, using components with incompatible voltage levels, and not properly configuring your programming or settings for your specific application. It is important to carefully follow instructions and double-check all connections to avoid these mistakes.

Similar threads

Replies
2
Views
877
  • Electrical Engineering
Replies
10
Views
1K
Replies
25
Views
5K
Replies
20
Views
1K
Replies
37
Views
4K
  • Electrical Engineering
Replies
16
Views
2K
Replies
4
Views
3K
  • Electrical Engineering
Replies
9
Views
962
  • Electrical Engineering
Replies
6
Views
4K
  • Electrical Engineering
Replies
10
Views
5K
Back
Top