LidarTestingUtility
This utility is used for testing LIDAR in non-scanning mode. It can be used for changing all parameters of the LIDAR.
Also it is used for testing work of the LIDAR.
It looks so:
All communication with LIDAR are made by serial port.
Button "Start" is used for sending "batch" measurements request (100 measurements).
"Auto Request Batch" checkbox is used for sending "batch" requests periodically (twice per second).
Left table is used for displaying raw measurements results from the TDC. "START" column is delay between laser pulse and received signal, "WIDTH" is pulse width. "CORR. START" is calculated by utility from "START" and "WIDTH" data by calibration formula. All values in TDC BINs.
A field at the center of the utility is used for displaying data analyze results.
"AVR TOF" - average value of "START" column.
"TOF std. dev" - standard deviation calculated from "START" column data.
"Max diff": maximum "START" values scattering.
"Corr AVR TOF"- average value of "CORR. START" column.
"AVR WIDTH" - average value of "WIDTH" column.
"WIDTH std. dev" - standard deviation calculated from "WIDTH" column data.
There is a histogram under the results text field. It shows "START" column values scattering. Horizontal axis is in BINs, vertical - number of measurements.
Right panel is used for controlling and setting parameters of the LIDAR.
"Auto requests" - send request for settings periodically.
"Laser Volt" - power voltage of laser module.
"APD Volt" - measured APD voltage.
"APD PWM" - current PWM width in timer ticks. Can be set manually.
"APD Targ. Volt" - APD target voltage. Used in auto-feedback mode.
"APD Volt. Feedback" - type of APD voltage controlling - manual (set PWM) of auto (set voltage).
"Comp Volt" - TIA comparator threshold voltage.
"Ref distance" - distance to a reference object. Used with non-scanning firmware only. You need to enter current distance to the object (in mm) and press "SET" button. This is a part of zero distance calibration.
"BIN Length" - current TDC BIN length in mm. This value can be changed by "SET" button.
"Raw TOF" - current delay between laser pulse and received signal, in BINs.
"Raw TOF width" - current received pulse width, in BINs.
"Distance" - current distance to the object. Calculated by firmware. Zero if delay correction coefficients are not written to MCU.
"State Mask" - bit field with current device state. See this description.
"Info" button - get description for active bits of "State Mask".
"Reset MCU" - send reset MCU request.
"Save to Flash" - request to save current MCU settings to Flash, including calibration data and motor settings.
There is a special function of logging averaged captured data presents in this utility. It is used for delay calibration. Logging is controlled from "Slow Recording" panel. Measurements are saved to the application path. Do not change any Lidar parameters during logging enabled - or it will give wrong measurements for calibration.
This page is used for calculating delay correction coefficients. See more information here: Walk error calibration
You need to load captured log file by pressing "Select File". After that a delay distribution plot will be shown. Horizontal axis is "WIDTH" in BINs, vertical axis is "START" offset (minimal "START" value from the log is used as zero level) - in BINs.
You need to move "Fit Start" slider to set start position of the fitting process and press "Fit" button.
The resulting curve would be shown with a red color like at the picture above.
If this resulting curve looks fine, you can load its coefficients to the MCU by pressing "Send Coeffs. to MCU" button.