Driver for VL53L1x

[shizacat]

Driver for distance sensor: vl53l1x
The second attempt
Single commit from #15565

[dagar]

Given the relatively huge number of registers and the poorly documented nature of this device did you consider leaving the ST ultra lite driver mostly intact and writing a simple wrapper to make it use PX4 I2C within a typical module?

[shizacat]

I decided this will be not comfortably and excessively for code. The most functions repeat standard functional any I2C device (read, write). All settings registry stored in VL51L1X_DEFAULT_CONFIGURATION and they don't have need to change them.

I actually followed the guide UM2510:

6 Reducing the driver size to its absolute minimum

Although ST have attempted to create a small driver, it might not be small enough for some applications. To
create the smallest possible driver, try the following approach:
• Use the current driver and configure the parameters as required. Start ranging (to show that it works).
• When satisfied that ranging works, dump the contents of the sensor from the location 0x2D through to 0x87.
• Replace the default register settings in the the array VL51L1X_DEFAULT_CONFIGURATION[] which is located in the file VL53L1X_api.c.
• This makes your settings the default settings
• Your main routine then needs only to call the the VL53L1X_SensorInit() function and VL53L1X_StartRanging().
• Most other functions can then be removed

[dagar]

I decided this will be not comfortably and excessively for code. The most functions repeat standard functional any I2C device (read, write). All settings registry stored in VL51L1X_DEFAULT_CONFIGURATION and they don't have need to change them.

It's not too much code, and I'm not worried about the I2C functions. What I don't particularly like is all the registers and bits that as far as I can tell are undocumented. Anyway, my gripe is with ST and this device, thanks for your effort.

Can you comment on testing and share a test log if you have one (https://logs.px4.io/)? I'm happy to merge this if it's otherwise working.

[shizacat]

EKF2_HGT_MODE - set to use range sensor. And I look at the plot 'distance sensor'. May be have errors in setup, or need check some thing, tell me.
https://logs.px4.io/plot_app?log=2b4681da-9c1d-49ac-8d74-1614d0cd5889

[dagar]

EKF2_HGT_MODE - set to use range sensor. And I look at the plot 'distance sensor'. May be have errors in setup, or need check some thing, tell me.
https://logs.px4.io/plot_app?log=2b4681da-9c1d-49ac-8d74-1614d0cd5889

It appears to be working, although clearly not as well as other common range finders. Perhaps not bad for a $4 sensor...

For your setup I would suggest using range aid (EKF2_RNG_AID) rather than EKF2_HGT_MODE and then make sure you tune the noise and gate appropriately for this sensor.

Thanks @shizacat

[dagar]

@shizacat FYI your git commit is missing your email address.

[dagar]

Note, for regular users to actually make use of this we'll need to add a parameter to actually start it (eg SENS_EN_VL53L1X).

[orkunasa]

#16346 @dagar