Groundspeed with wheel encoders (optical sensors) on ArduBoat

Hi all. I want to build a boat on PX4 autopilot (1 megabyte memory),
ArduRover firmware version 4.4.0 without using
GPS. I used the manual for connecting encoders
Wheel Encoders — Rover documentation, two optical sensors were purchased
MH Sensor Series on the LM393 chip, connected according to the manual and was able to get it on the table
distance traveled in MAVLink Inspector. But without GPS I couldn’t get groundspeed. I also noticed that when
With GPS turned on, I get both groundspeed and airspeed, but in the parameters airspeed is turned off.
In the mission I set it to set ekf origin here.
GPIO is configured correctly and tried on different aux.
I adjusted the amount of rotation and radius so that it could be checked on the table, I placed the sensors
so that the overlap is 50%, I get the distance traveled, but the rover does not move on the map
and does not display groundspeed. Please tell me what may be configured incorrectly or
What should I figure out next to get groundspeed data? I read a lot of manuals and searched
the problem on the forums, but I still can’t solve the problem. Thanks in advance for your attention
to my problem and I apologize for the possibly incorrect spelling of the text, since I am writing through a translator.

Hi @Savik69,

If the vehicle isn’t moving on the map then the EKF probably doesn’t have a good position estimate which can happen for lots of reasons. It could also be that the EKF origin hasn’t actually been set.

An easy way to check if the EKF has a position estimate to connect with MP and click on the EKF label on the HUD. If some of the “Flags” are red then it probably doesn’t have a good position estimate.

If you have log I could look in more detail.

Thank you very much for your help, I will try to provide parameters and a log describing my actions in the near future, since I am currently testing everything modularly before assembly.

Hello, I’m sorry I couldn’t answer earlier.
I recently found a topic on developing a speed sensor relative to water, it really interested me and I used the materials and made it. I liked it much better in my work and I am sure that I can get a more accurate speed of the boat than through an encoder. Thank you for deciding to help me, but now I will receive speed from two such speed sensors as in this topic. Thank you @Mckey

1 Like