If you wanted to go with an actual RC PWM to voltage converter they are out there.
I would worry a bit about tying this to the motor ESC (they are noisy and might fry the PWM to voltage converter). It would give you a lot more linear response and full range of voltage). A low pass filter will be more damage resistant or even the potentiometer- servo setup. No spurious voltage spikes can get back into the flight controller on the potentiometer-servo setup.
Thanks!!!
I tried looking for something like that earlier but never could find one. Then I search using the description of the product you linked, and then more of what I was looking for showed up. Guess you have to gave the right terms.
I went to the link you sent and added it to my cart to buy, but it was going to be about a month for it to arrive, plus $20 shipping.
I found a few other and going to give them a try.
Thanks again!!!
With the servo adaptor, I was going to see about attaching it to actual Ryobi hall effect sensors. This way I would not have to worry about tying anything in. Just a bypass switch to go between the hall effect sensors on the mower’s control arms and the external hall effect sensors for the Adrupilot.
Thanks again.
Most of those PWM to voltage converters you listed are not for the right frequency. They have to say for RC use which makes them work at 60 Hz.
Thanks, I was able to cancel them. Kept one, stated it had a input signal frequency: 22Hz- 20kHz. Something to play with…
I ordered two types of RC low pass filter, one you suggested and one that I found that was in the 60Hz rang. Not quite sure about the wiring. Here is a diagram of both modules with what I think is correct.
Any suggestions/corrections would be greatly appreciated.
The wiring looks fine to me, as far as I understand things. Those are true digital PWM voltage converters (at least the one on the right is and it should have a linear output curve). The other one is a motor controller that should work in the frequency range you need. It might have a linear output. I am not sure if the output being linear matters that much.
A simple RC low pass filter looks as follows:
@Kevin_OBrien had mentioned he was going to try an LC low pass filter on his Ryobi interface. I would be curious to know how that worked. I think a low pass filter made of a resistor, inductor, and a capacitor would make a better filter.
Thanks,
I do like the simpler way, making sure on the resistor value and capacitor value is what I am worried about… I have a new meter with oscilloscope coming in this week. Will be testing the output of the existing position sensor.
I replied to @Kevin_OBrien post and sent DM to him.
I don’t believe any of those adapters will convert an RC PWM signal. RC pwm is a pulse between 1 and 2ms every 50ms so its only effectively changing by 2% you would need something to read it as a protocol not duty cycle.
I would believe @geofrancis. In the article mentioned, all the examples are at much higher frequencies. That is all industrial motor control stuff. That digital 60hz PWM to voltage converter should work just fine though, it was designed for RC control stuff.
Thanks, for the head’s up @geofrancis!
you could do it with an Arduino board.
I just done the first test of my hoverboard hover mower, unfortunately the blade esc burnt out almost immediately, so I didn’t get to cut any grass. I’m probably going to use a ebike controller next, they get expensive because it’s a 48v battery.
Still working on which way to go. Do not have a garage so having to do what I can between rain/weather and after work, which has not been in my favor.
As I mentioned earlier I did order 2 module:
Received but have not played with.
Waiting:
Still figuring out the Resistor Capacitor (RC) Low Pass Filter and how to figure out the value for the resistor and capacitor, paranoid about screwing thing up. But I’m favor of simpler the better.
Note: The use of RC gets a little confusing and searching (google).
RC = Resiistor Capacitor
RC = Radio/Remote Control
But Still Learning…
Also came across this…
I like the looks of that latest proportional PWM to Voltage converter. I would suggest measuring the variable voltage output of the existing handle sensor to find out what voltage is required to make it go full forward and full reverse. It just seems like a logical test to keep your design on track.
Thanks, that is the plan. As mentioned, I do not have a garage so I have to work on a lot of things after work and between rain/storms. Got a new 2 in 1 oscilloscope multimeter to do some testing with. Once I figure the oscilloscope out…
first test cutting grass, I had to replace the blade motor controller with one from an ebike, im driving it using pwm from a micro controller smoothed using a capacitor. no gps yet, its just me driving manually. first part is at half power just until i was sure nothing was going to break off then i turned it up to its rated 700w. I need to fit better tyres, they are just slipping when trying to reverse.
That is pretty impressive for a DIY mower and it seems to work pretty well!
i was trying it today with its pneumatic tyres on 3d printed wheel adapters
Bigger tires on these small mowers are usually much better to keep from getting stuck.
