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I have been trying to create a sensor that detects when a golf club hits a golf ball. My idea was to have a lidar sensor to continuously poll the head of the golf club, and return a positive indication when the distance has changed significantly. To do this, I use the VL50l0X. However, as I get further away from the golf club (>15cm only), the lidar stops sensing where the head is, returns an out of range signal. I have tried different range profiles but the same error is returned.

It is connected to the 3v3 output on an arduino uno, using the example code provided by adafruit.

I believe this may be due to the fact that the golf club is angled away from the lidar (about 70 degrees), as, when I substitute the golf club head for a flat surface, it works as intended. I would like to ask if there are different sensors I can look at to this application, or some other way to approach this problem. I was advised that a shock sensor would not be the best idea due to the time difference between the golf club hitting the ball and the sensor.

Link to VL53l0X datasheet

vernal123
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  • You can't make the golf club face more diffuse? – DKNguyen Feb 22 '22 at 16:38
  • Thanks for replying! Not in particular because the problem statement was to use commercially available products. However would this be done by polishing the face in some way? – vernal123 Feb 22 '22 at 16:41
  • Not polishing. The opposite: roughing up a bit. Like 600+ grit sandpaper but I don't know if that is acceptable. Try just masking tape first though to verify that is the problem. Or maybe a marker or dull pain that can be easily removed if the face doesn't have grooves. – DKNguyen Feb 22 '22 at 16:41
  • I will try that thanks! Off the topic but do you know other sensors that could solve this issue too? – vernal123 Feb 22 '22 at 16:44
  • Ultrasonic....maybe? But affected by more environmental stuff and lower sample rate. Oh yeah, plastic-type materials are often transparent to your your IR beam is transparent so some paints or tape might not work. – DKNguyen Feb 22 '22 at 16:44
  • I worry that an ultrasonic sensor might be too slow for a golf ball to detect :( but thanks for the reply! Out of curiosity are there more powerful lidars – vernal123 Feb 22 '22 at 16:50
  • Yes but expensive and not user friendly. – DKNguyen Feb 22 '22 at 16:50
  • Hi, sorry for the late reply, I finally had time to spend on the project. I tried using masking tape/retroreflective spray, and I think I isolated the problem to the lidar not being able to detect "small" objects. If you have the time, I would greatly appreciate your guidance on this. – vernal123 Mar 16 '22 at 08:33
  • Not sure how to deal with that to be honest. – DKNguyen Mar 16 '22 at 13:21
  • Thanks for you reply, I might have to pursue other sensors as I believe currently my LIDAR is unable to produce the readings I want it to. – vernal123 Mar 17 '22 at 01:07

2 Answers2

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Just use a microphone. There is a fairly loud, distinctive sound when the club hits the ball.

Elliot Alderson
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Try using a retroreflector to return the lidar signal back to the origin, or maybe a matt textured white paint would be sufficient.

With regard to a shock sensor, a simple piezoelectric device would should have a quite short (and predictable) response time, for example some sensors are under 100 microseconds.

jayben
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