teckel:
We got lucky for sure. Is it reading accurate distances? 3 distances are a good test (10cm, 50cm and 200cm) something like that. It probably won't be prefect, but within about 1cm is about the best you can hope for with ultrasonic sensors. As it is now, we're assuming 50uS is really 1cm. Also, you should probably try to test the ping_in() method to make sure the inches are also correct.I've implemented changes to the NewPing Library to a allow support for the URM37 sensor in PWM mode. v1.6 will include this support. There's a URM37_ENABLED define you set to "true" to enable support (which measures the low signal length instead of the high and adjusts the length so each 50uS is 1cm).
Tim
I did some measurements, the distance of the following looks good :-
10cm - ok
50cm - ok
100cm - ok
150cm - ok
200cm - ok
With +/- 1 to 2cm variance for distance above 100cm...
I have a strange issues, one of the URM37 sensors, after operating for 7-9 hours, it just stop working... ( I think this is related to the sensors and nothing to do with the NewPing lib ), even after I do multiple reset, it is still not responding and gives a 50,000us ( means reading is invalid )...
I'll report this issue back to DFRobot for this...