PWM converter

1

Hi all

I’m in the process of building a robot tool carrier that will use AOG for navigation when mowing however the speed controller I’d like to use for the steering only supports standard RC PWM and not the PWM plus direction output the Arduino has.

Has anyone built a converter that would change the PWM output of the AOG adruino to an RC signal?

I’m guessing another nano would be good for this however I’m not at that level of coding yet (I can make an LED blink though)

Cheers

2

Would the ibt_2 output work? Has a line for left another for right, third line is on /off
Maybe put it in Danfoss mode so you have center at 6 v, and combine with following info

3

Thanks for the links, time for some reading!

I don’t think either the IBT2 or danfoss outputs will work unfortunately, from what I understand the RC signal is 1ms one direction, 1.5ms center and 2ms other direction on one wire.

4

You can use the standard servo library and with some code changes output RC pulses on either of the two PWM outputs. When I did this (using a brushed reversible ESC) I had to experiment a bit to find the correct center position timing.

5

So you have to make an algorithm that convert the Danfoss center pwm value of 2.5 V to 1,5 ms. And below 2.5 V gives 1ms and over 2.5 V gives 2 ms
I even think Danfoss center can be adjusted in AOG

6

Is it something like this you want? (flysky rc için)
2
1

7

This looks similar to what I’d like to do, does the Arduino receive the input from the RC receiver and convert this to a different signal for the motor driver? This what I’d like to do but in reverse where the input to the Arduino is from AOG and the output is servo pulses.

Sounds like there’s a couple ways to do this, I’m thinking if the Danfoss system can be adjusted inside AOG then maybe I can use a second nano to do the conversion to the RC pulse and maybe somehow incorporate this with 4 wheel steering control.
I think I’m going to need to do more reading on programming Arduino lol

8

Yes, this is how I use it when manually controlling my own vehicle.

9

2
I don’t understand what is happening here. What is the L293D doing?

10

L293 dc motor driver is produced to convert RC mini servo motors, mini servos 1-1.5-2 msec. produces pulses in time interval, pwm outputs are not available in most models, this circuit converts servo signals to pwm.

11

Had a bit of a brain wave (or maybe brain fart) thinking about this earlier.

I have seen small servo testers that use a 555 timer to generate a signal for standard RC servos with a potentiometer to adjust the position powered by 5v. Some even have adjustments to center the servo using another potentiometer.
Could the PWM output from the Arduino be used to drive the 555 timer in place of the potentiometer with the output set for danfoss mode?

I know this could all be done with a modification to the ino but this also means in future updates the ino wouldn’t need to be changed.

12

I implemented this as a simple solution for speed control on my own vehicle.

13

So I’ve assembled my v2 board and everything seems to be working OK, to select danfoss mode do I just select IBT2 and the danfoss logo in the AOG settings then send to steering controller?

Not getting any pwm output from the board as yet, I tested my servo driver separately and that’s all working OK too. I’m not sure if maybe I’ve missed a setting somewhere.