Acoustic sensor setup with Pixhawk

[Samir_Stevenson]

Hi I’m working with an acoustic sensor that has 3.3v, RX, TX, and GND pins. I got it working with my Arduino MKR zero but when I tried connecting it to Pixhawk over Serial4/5 port and through the Aux out pins I didn’t get any data. I used this page as my main reference.

[anon53993083]

not sure if you have had a look here but if its an unsupported sensor then you might want to try using these setup instructions to get the data fed back to mission planner

Unsupported Sensors? Try Arduino + Lua!

In a separate/private conversation, I was asked whether Lua provides a built-in map() function like the one provided by the Arduino libraries. I thought the answer might be of use to some of you: To my knowledge, there is no map() function provided natively in Lua. Here is the Arduino map() function from WMath.cpp: long map(long x, long in_min, long in_max, long out_min, long out_max) { return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min; } In Lua, it looks like this: …

[Samir_Stevenson]

Ill take a look thanks!

[geofrancis (GeoMuir)]

What sensor is it specifically.

[Samir_Stevenson]

This one.

[geofrancis (GeoMuir)]

Thats a sr04 v2 ultrasonic compatible sensor. What mode is it? What code did you use to test it on arduino?

You can get them with 3 modes, mode 0 is sr04 trig echo, mode 1 is automatic serial and mode 2 is triggered serial.

Mode 0 is supported as a sr04 ultrasonic GPIO rangefinder nativity by ardupilot

Mode 1 and 2 will need a converter.

Sonar JSN-SR04T

Great! I’ll try to compare its readings with Kogger Sonar.In Russia, the JS-SR04T is widely used as an echo sounder in homemade autopilots (based on STM32) for bait boats.

I had a look again, it looks like its mode 1 automatic serial mode that DFRobot are selling.

[Samir_Stevenson]

I used this library for my arduino. When you say Id need a converter what do you mean?

[geofrancis (GeoMuir)]

Ardupilot doesn’t support the sensor natively so you will need an arduino compatible board like a pro mini 168 or 328 16mhz to act as a converter to convert it from the serial data format that it outputs to something it understands in the case of the converter I linked it emulates a Maxbotix i2c sonar.

geofrancis/JSN-SRT04T-serial-i2c-adapter/blob/main/JSN-SRT04T.ino

[Samir_Stevenson]

I have an arduino Im using to get the distance readings. I dont know how to get the data from my arduino to ArduPilot.

[geofrancis (GeoMuir)]

Use the arduino sketch i posted and it will use the arduino to convert the sonars serial data to i2c maxbotix compatible data. Set ardupilot range finder to maxbotix i2c sonar.

[Samir_Stevenson]

I am using an MKR zero and the code above is for a different architecture and doesn’t work with my Arduino. I’m thinking I just get a supported sonar sensor to make this easier.