Why I'm Getting Signal Fail Error Status from VL53L1

[SGhay.1]

Hello Everyone,

I'm Using VL53L1 TOF sensor in Long Distance mode(4 Meter),But its showing error "VL53L1_RANGESTATUS_SIGNAL_FAIL " and Sometimes "VL53L1_RANGESTATUS_WRAP_TARGET_

FAIL" Changed TB and InterMeasurement Period from 33 ms to 200 ms.but still facing same error.

Till 2.2 -2.5 Meter getting valid data.

Thank You

[Julien NGUYEN]

Hi,

The max ranging distance of 4 m is given for a specific condition: dark, high target reflectance 88 %, and the FoV is totally covered by the target surface (2mx2m for 27 deg FoV and 4 m distance (trigo math)).

The VL53L1_RANGESTATUS_SIGNAL_FAIL code means that the return signal is too weak. Perhaps the target reflectance is too low or the target size is too small ? Increasing the timing budget will not compensate the lack of the return signal level, sending more photons (by increasing the TB) that will not bounce back will not help. Increasing the TB will help you to get more accurate measurement when the return signal is enough for the sensor to operate. Thanks, Julien

[SGhay.1]

Thank You for your quick Response.

I'm trying to detect human.so is there any way to detect human from 4 meter distance using same sensor.

Thank You

[Julien NGUYEN]

Hi,

It will be difficult or impossible for the device to detect someone at 4 m even in the dark because the return signal level will be not optimal due to the clothes reflectance ~50 % depends on the fabric actually, by assuming that the body shape covers the whole FoV, but it could be not the case for example when you want to detect the human by his head or shoulders... Julien

[SGhay.1]

what can be the maximum distance for human detection using VL53L1 ?