I am planning to interface sonar with ROV, which will be connected to pixhawk ADC pin (3.3 V). I am using hardware similar to BlueROV (raspberry pi and pixhawk). It requires high sampling rate too (800K).
Some of the resource I could find were related to Airspeed sensor adc interface.
I couldn’t find more resources over the internet. Require suggestion on the best possible way to read/sample ADC value from pixhawk?
Thanks for the post. What type of sonar are you using? I’m not sure the Pixhawk will be suitable if it requires very fast sampling rate or collection of a lot of data.
@jwalser may be able to help with the ADC measurement info.
Hi @johnstmathai, The pixhawk autopilot sofware runs on top of an RTOS. This type of sampling poses a few issues:
1: It will be hard, if not impossible to squeeze this rate of sampling out of the RTOS.
2: This rate of sampling will produce a relatively huge amount of data (12.8 Mbit) that will need to be processed and/or transferred.
3: The amount of time spent dealing with this data will interfere with the critical timing of the rest of the real-time program.
I recommend you use an independent processor to handle the sonar data.
Thanks for the quick reply. We might not go with the ADC sampling directly, instead will go with an intermediate processor and read data using Serial or Ethernet Interface.