is it possible to use a little servo with Duet 2 WiFi?

A Former User

@t3p3tony said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord said in is it possible to use a little servo with Duet 2 WiFi?:

but could the 3,3V signal from the heater pin in the expansion board drive the servo's signal pin?

yes

excellent, thanks, what other pin in the expansion connector can I use for it? Heater 3 is already allocated by the BLTouch

T3P3Tony

@thedragonlord to add, ensure your grounds are connected between the external supply and the Duet,

A Former User

@t3p3tony said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord to add, ensure your grounds are connected between the external supply and the Duet,

Yes, the external supply is a stepdown wich input is the 24VDC from the board's power supply so it's already ground-connected with the board itself. I've modified my previous post so maybe you haven't read my last question: what expansion connector pin can I use to drive the servo? heater3 is already allocated by bltouch

A Former User

@t3p3tony said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord to add, ensure your grounds are connected between the external supply and the Duet,

I have installed the servo using the heater 7 pin in the expansion connector, correctly configured it and it works but now the bltouch doesn't work at all... I though that two servos can be configured in the same board but they can't work at the same time. Have I misunderstood? Only one servo can be configured and working?

dc42

@thedragonlord you can configure and run more than one servo but they must have different GpOut port numbers. The port number is the S parameter in the M950 command and the P parameter in the M280 command.

A Former User

@dc42 said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord you can configure and run more than one servo but they must have different GpOut port numbers. The port number is the S parameter in the M950 command and the P parameter in the M280 command.

excellent, thanks

o_lampe

@thedragonlord said in is it possible to use a little servo with Duet 2 WiFi?:

but they can't work at the same time

To clarify that: they can work at the same time, but it might overload the internal 5V supply. (I wouldn't dare to try, since it can kill the Duet)
With a strong external 5V source, you could drive more servos

A Former User

@o_lampe said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord said in is it possible to use a little servo with Duet 2 WiFi?:

but they can't work at the same time

To clarify that: they can work at the same time, but it might overload the internal 5V supply. (I wouldn't dare to try, since it can kill the Duet)
With a strong external 5V source, you could drive more servos

I have an external 5V step down connected to the main 24Vdc power supply to power them

A Former User

@dc42 said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord you can configure and run more than one servo but they must have different GpOut port numbers. The port number is the S parameter in the M950 command and the P parameter in the M280 command.

is it possible to change the angular speed for the movement?

o_lampe

@thedragonlord Angular speed of a servo depends on Voltage. But a low voltage makes it weaker, too.
You can also slow it down by writing a macro that changes the angle step_by step with a pause between, but that's not a smooth slow move.

A Former User

@o_lampe said in is it possible to use a little servo with Duet 2 WiFi?:

@thedragonlord Angular speed of a servo depends on Voltage. But a low voltage makes it weaker, too.
You can also slow it down by writing a macro that changes the angle step_by step with a pause between, but that's not a smooth slow move.

ok, thanks

achrn

@thedragonlord said in is it possible to use a little servo with Duet 2 WiFi?:

is it possible to change the angular speed for the movement?

There are plug-in gizmos to slow down servos, used by radio-control planes that want (for example) the undercarriage to retract at something like a realistic scale speed even if teh transmitted signal is just 'up' or 'down'. They simply plug between the receiver and the servo, so I don't see why you couldn't plug one between the Duet board and the servo.

See https://www.youtube.com/watch?v=oGJ7ymBBa2c from about 1:45 for example (but I have no idea what he's saying - maybe he's saying this unit is no good at all).

o_lampe

@achrn Right, they do the same as described above. It's just a matter of super-fine steps and shortest pauses, how smooth it looks. It's worth a try with Duet MPU clockrates.
I've seen videos of "lynxmotion hexapods" where a similar mpu controls 18 servos fluently