LED to show laser alignment.

Other Hardware Sensors
1

Dear all.

I am currently making a laser speed trap to measure egg race contraptions at my school.

Using laser diode with photodiode sensors on inputs 2 and 3.

All is working well, but I would like to write into the code a visual (LED) sign that the sensor are each aligned. And more importantly when they become misaligned.

I have tried to write in if digital read etc at the beginning of the loop, but it either does not compile the LED remains on even if I move the sensor out of alignment.

Any help gratefully received.

Regards

Jon

CHRONO_sketch_from_Arduino_site.ino (1.27 KB)

2

Can you please supply a picture showing how the laser is set up so we can see how it is aligned.

Weedpharma

3

Pic attached

Lasers are independent of arduino to save trailing wires, coding etc

cannot have a gantry as vehicles maybe too high

many thanks for your help.

Jon

4

Pic attached (RESIZED)

Lasers are independent of arduino to save trailing wires, coding etc

cannot have a gantry as vehicles maybe too high

many thanks for your help.

Jon

20160614_120623 (800x450).jpg
20160614_120623 (800x450).jpg800×450 80.5 KB

5

The problem is going to be how do you tell if the lack of signal is due to obstruction or misalignment.

I would use a timer that would alarm if the lack of signal was longer than the expected time due to object passing through.

Weedpharma