Any suggestions for PWM projects to explore?

Projects General Guidance
1

Hello,
For a minimalist robotics project, I am looking for a PC controller solution for small PWM servomotors.
If I've read correctly, an Arduino Mini has 6 PWM ports, possibly with precise control, and a USB port.
That would be ideal for me.

What I envision: with a protocol to be defined via the USB-Serial connection (e.g., Modbus or a simpler ad-hoc solution), the PC sends commands to the Arduino, which decodes them and applies them to its PWM outputs.

But I'm afraid there are many small practical problems to solve... so if anyone knows of an existing project that already does this, that would be great.

Best regards

2

What kind of exactly? Normal 50Hz hobby servo or something more exotic.
Servo library can drive normal 50hz hobby servos on any pin.

3

Yes, standard 50 Hz hobby servo are just what I need. A standard simple robotic arm typically requires between 4 and 6 degrees of freedom. If I’ve understood correctly, the Servo library uses the Arduino’s three dual timers – that is, six PWM ports – and allows controlling the pulse width with good precision. So it’s perfect.

4

You might have missunderstood what you have read. While a servomotor uses "a form" of PWM, it is not the form that that you get from PWM enabled pins.

Your best bet is to use the servo library.

No that library does not use the PWM pins of the board. Timers and PWM pins are not the same thing.

5

Then you can use about any arduino board that has USB.
You also need beefy power supply for multiple servos, don't try to power them from arduino.

6

googling "control RC servo from PC" turns up tons of existing projects.

7

The control software looks interesting.

8

If you are looking for a bunch of pwm channels that takes the load off your Arduino, take a look at the PCA9685.

16 channels, I2C interface with built-in pullups and 220 ohm resistors on the signal outputs.

9

As you have been told, the servo library doesn't use PWM and can drive up to 12 servos on a simple Uno R3, Nano v3 etc.
That said, it could be better to offload that computer power to an external servo driver, like the PCA9685 (see second small picture). Then your processor becomes 'set and forget' and can do other things faster.