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Prop-based vehicle speed measurement — Parallax Forums

Prop-based vehicle speed measurement

Not sure if this is of interest and/or has been done before, but...

After getting annoyed with vehicles speeding past our house, I have connected two Benewake TFS02 LiDAR sensors to a prop and pump the timing data to my PC.

One cog per LiDAR sensor, using FullDuplexSerial at 115 200 baud to take distance measurements at 500 Hz. They are basically being used as beam-break sensors without needing a reflector on the other side of the road; the distance readings also allow me to determine which lane the vehicle is in. The values of cnt at each "beam-break" event get passed to my PC via FullDuplexSerial at 9 600 baud and Excel does the maths. Because I know when the vehicle first 'broke the beam' and the last point it was still 'breaking the beam', I send the latter as well and can estimate the length of the vehicle.

Four data pins, four LEDs.


Parsimonious with RAM:

Comments

  • JonnyMacJonnyMac Posts: 8,097

    Neat!

  • I am trying to use Extended Full-Duplex Serial Object

    I continue to get an error message: Illegal Circular reference
    I I
    ------- Extended_ FDSERIAL

    I can not figure out what to do now...... any suggestions THANKS John

  • PublisonPublison Posts: 12,329
    edited 2022-06-23 00:17

    @6aerobat said:
    I am trying to use Extended Full-Duplex Serial Object

    I continue to get an error message: Illegal Circular reference
    I I
    ------- Extended_ FDSERIAL

    I can not figure out what to do now...... any suggestions THANKS John

    MODERATOR EDIT: Please keep the question in this thread. Posting in multiple thread are not allowed.

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