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Questions &/or issues related to products in the Robotics category should be posted in this forum. Includes Direct Current(DC) Motors & Drivers, General hardware & Chassis, Servomechanisms(Servos) & drivers, Stepper Motors & Drivers, etc.
#207226
Our team has been working to build an Autonomous Vehicle for a school project and we've been shifting from many different options for controlling the motors and servos of our vehicle.

Initially we only had our personal Arduinos that we used to handle both the Motor and the Servo, however eventually that proved to be a bottle-neck where the constant serial communications resulted in the Arduino crashing.

We've now moved on now that our school has supplied us a Flipsky Electronic Speed Controller specifically this: https://flipsky.net/collections/electro ... controller However this has no PWM output so we can not control the servos of our vehicle.

We've looked at several options from a Adafruit PWM Interface: https://www.adafruit.com/product/815 to a Sparkfun servo driver: https://www.sparkfun.com/products/9664

We've also considered just using the Arduino or getting a small Arduino board to use exclusively for servo connections, but we really want our code to be as centralized. We are mainly staying with Python as our main language and Arduino boards required us to write C++. So whatever we pick would preferably be easily controlled with the python serial library.

Any advice or is what we are looking for wrong? Saving money is very important to as this is a public school and whatever we buy will eventually be needed by four more groups when they encounter the same issues as us.

Is there a devices I haven't found yet? Any solutions we haven't tried with the FSESC? Any advice is helpful.
#207232
Hi BSBussell.

What are you using for a controller? An Arduino or something else?

I don't know anything about the Flipsky Electronic Speed Controller, but from looking at the data sheet, it will receive a PWM input from a receiver so anything that will drive a servo should work with it. There's a good chance you won't need anything but a GPIO pin that can send a valid servo PWM signal and if you have a spare pin on your controller that can do that, you wouldn't need to buy anything else.
#207279
I would have assumed that a Jetson would have the capability of generating a PWM signal on a free GPIO pin to drive a servo but I've not been able to find an example where someone has done that. Not sure if there isn't enough current available to do it or if there's some other technical reason why that won't work.

I have however seen several examples of using a PCA9685 chip connected to the Jetson to drive servos. The PCA9685 is a 16 channel PWM generator chip that you can connect too over I2C and had the capability of driving servos and should work with your speed controller. Our Servo pHAT for Raspberry Pi should work but it's not been tested on the Jetson before and we don't have any code for using it with the Jetson. This might be a possible solution for you.