Hey guys,
I was wondering: The HY-SRF05 ultrasonic distance sensor has a transmitter and a receiver. Both have a length of roughly 1cm and are mounted on the circuit board. Now, the distance that is returned from this sensor, is it the distance from the circuit board to the obstacle, or the distance from the end of the transmitter to the obstacle?
Why don't you measure it?
Luk_11:
Hey guys,I was wondering: The HY-SRF05 ultrasonic distance sensor has a transmitter and a receiver. Both have a length of roughly 1cm and are mounted on the circuit board. Now, the distance that is returned from this sensor, is it the distance from the circuit board to the obstacle, or the distance from the end of the transmitter to the obstacle?
Neither. The distance is a function of when the counter started and stopped.
You are digging too deep. It doesn't matter where is the start point is, because the sensor has accuracy +-3mm if it 90deg dead to the obstacle!!!
Well... I am trying to determine the accuracy of this sensor. Therefore, what I do is:
I measure the distance towards an obstacle with measuring tape. Here, I consider the distance from the obstacle to the circuit board. However, it seems the sensor doesn't return this distance, but the distance from the end of the transmitter to the obstacle. Even this, however, doesn't always hold, not even within the +- 3mm range.
So, if you were to perform such an experiment, which distance would you measure?
If you really need to have greater accuracy use two sensors, mounted on top of each other, and compare the result set, discarding the result sets that do not match.
Eliminate all possible sources of ultrasonic emissions such as energized motors and humidifiers.
The other option is to consider using a LIDAR
Time of flight IR is much cheaper (VL53L0X or LV53L1X works great), and gets easily within 3 mm accuracy, and the second has a range that's almost as far as ultrasound.
LiDAR indeed does better and has even longer range.