modifyiong Servo control signal
01-04-2022, 02:08 AM
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modifyiong Servo control signal
Has anyone seen any general circuits for modifying the Pulse width modulated output of the servo signals?
I'm looking at a project, and want to use the output of one of the servo channels to drive a pheumatic control valve, ramping it from fully off at joystick centered, to fully open at full joystick throw, and modulating the valve at intermediate positions via a PWM 10 Hz signal.
The bulk of the circuit won't be a real challenge for me, but the part I'm struggling with is converting the 5-10% duty cycle signal to any easily usable format, like a 0-5V dc signal that could be used to then control the pule generator.
Has anyone seen any plans for converting the PWM signal from a servo control signal to any other control format?
I'm looking at a project, and want to use the output of one of the servo channels to drive a pheumatic control valve, ramping it from fully off at joystick centered, to fully open at full joystick throw, and modulating the valve at intermediate positions via a PWM 10 Hz signal.
The bulk of the circuit won't be a real challenge for me, but the part I'm struggling with is converting the 5-10% duty cycle signal to any easily usable format, like a 0-5V dc signal that could be used to then control the pule generator.
Has anyone seen any plans for converting the PWM signal from a servo control signal to any other control format?
03-24-2023, 11:29 AM
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Hello: If you know how to write code for the Arduino micro processor then use the ATtiny85 chip. I have made many RC projects using the ATtiny85 from Microchip. It is a very cool 8 pin dip. What you want can be done, but you will have to do it. Like I said I have made many RC projects using the Arduino code on the ATtiny85 chip. Works great..
good luck
good luck
03-24-2023, 06:50 PM
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I'm mure of an od-school analog junky.
I forsee building a PWM Demodulator, converting the PWM signal to an analog voltage. Run the analog voltage through an op amp, to offset the signal so the neutral joysick yilds a zero volatage output, and full up deflection of the joystick yield a full (5V?) output of the demodulator??? any down joystick would then also keep the demodulator output at zero volts, making down joystick movement irrelevant.
the modified 0-5V output would then be fed back into a PW modulator. I also plan on doing a slight window comparator test on the modulator input voltage so that the modulator output will stay at a zero output until about 20% (or whatever value I find yields a minimal useable pneumatic pressure) up stick is is deplayed, and any deflaction beyond an upper threshold would result in a 100% duty cycle output. (I know many modern radios have that function effectively programmable in the transmitters...)
I'd also like to implement a fail-safe, where a loss of carrier would shut off the pneumatic valve.
I forsee building a PWM Demodulator, converting the PWM signal to an analog voltage. Run the analog voltage through an op amp, to offset the signal so the neutral joysick yilds a zero volatage output, and full up deflection of the joystick yield a full (5V?) output of the demodulator??? any down joystick would then also keep the demodulator output at zero volts, making down joystick movement irrelevant.
the modified 0-5V output would then be fed back into a PW modulator. I also plan on doing a slight window comparator test on the modulator input voltage so that the modulator output will stay at a zero output until about 20% (or whatever value I find yields a minimal useable pneumatic pressure) up stick is is deplayed, and any deflaction beyond an upper threshold would result in a 100% duty cycle output. (I know many modern radios have that function effectively programmable in the transmitters...)
I'd also like to implement a fail-safe, where a loss of carrier would shut off the pneumatic valve.
