How to use Wheel tick sensor in Sparkfun ZED F9R in Dead Reckoning mode?

GPS/GNSS
1

How to use Wheel tick sensor in Sparkfun ZED F9R in Dead Reckoning mode ?
I want to tracking of tractor on outdoor it is more accuracy but sometime i want to tracking indoor in warehouse (width 120 meters)

How to use Wheel encoder with Sparkfun ZED F9R to get direction and wheel speed for more accuracy indoor (Youtube example tracking can use indoor and outdoor when use it together sparkfun GNSS RTK and wheel encoder)

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sparkfun ZED F9R have pin of w+ w- (wheel) and d+ d- (direction) how to use it

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Can you put a wheel tick sensor on your tractor?

By hardware, you can send wheel tick to the F9R, as you mentioned.

You can also send wheel tick or speed by software.

Direction is not mandatory but I would recommend it on a tractor.

BTW, if your tractor looks like the one above, it’s mechanical behavior is different from a car, with all front axle turning and not only wheels. It may disturb F9R fusion engine.

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If you can recover REAR WHEEL tick(s) via CAN bus or something, injecting them via software would be more ideal.

Also I seem to recall fusion requires speeds of 30 kph or so, so perhaps not ideal situation for slower moving vehicles.

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Does it mean I can get rear wheel tick or speed or direction data on the ESP32 via CAN bus and send it to the SparkFun F9R using software or hardcoding?

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Basically Yes, there are UBX-ESF-MEAS forms where you can push data into the ZED-F9R
Different sub-messages for different wheels, and speed/direction (velocity signed), or wheel encoder ticks. The ESP32 or whatever can manage the RTCM3, CAN and other care taking tasks. I’ve used Arduino’s to drive motors and implement way-point following / processing.

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It is correct ?, I will calibrate the IMU sensors (gyroscope and accelerometer), store the calibrated values of X, Y, Z, yaw, roll, and pitch, and use an ESP32 to send the calibrated data via ESF-NMEA to the SparkFun F9R.
This method is intended to avoid repeated calibration. Alternatively, is there another method to save the IMU calibration? Save calibrate in u center one time after calibrate ?

For the speed sensor, I will get the data via OBD2 and send it to the SparkFun F9R to enable dead reckoning mode (IMU + wheel speed).

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There are two aspects in “calibration”. One is calibration of IMU (and wheel tick). It has to be been done, especially because it is temperature sensitive. The other one is IMU alignment. One can do it using auto-alignment or one can give values manually. As mentioned by clive, auto-alignment needs to drive higher than 30 km/h to converge (and better above 50 km/h). Most likely, as mentioned by Clive, you will not be able to achieve auto-alignment. You will need to carefully install the IMU and it alignment values.

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