Asked — Edited

Ultrasonic Sensor In ARC Using Collision Avoidance Control?


When using the ARC Ultrasonic Collision Avoidance Control, does the readout in the Ultrasonic Sensor Window show inches? it seems that it is reading in centimeters and not inches with the Collision Avoidance Control. if not the reading in the ARC Display is pretty far off. To get a fairly accurate reading, should I be using the Distance Measurement Control? Any clarification and/or comments would be much appreciated.Thanks Much ! Rick Bonari


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Any comments on the previous post would be appreciated. Thanks Much..Rick Bonari


There is no unit of measurement. The unit is arbitrary related to the type of sensor, voltage, detected material, and operational temperature. If you require specific distances, measure the distance with a tape measure at the most optimal use-case and record the number.



I have the ez-robot ultrasonic sensor. When I put my hand at various distances the value changes in readout as I would expect. If I understand what you are saying the value is just relative and doesn't represent inches or centimeters as far as the readout is concerned? Could a script be created to get raw value from sensor and convert to inches?

I tried the radar control with my adventure robot. When I hit clear button would expect the radar screen to clear but it doesn't. Also range markings on radar screen don't seem to track actual distance of object from robot. Is there something I am missing with the radar control setup. I don't have the sensor mounted on a rotational servo on adventure robot so maybe this is an issue also?

Thanks Much ! Rick B.

  1. a script can be created. Use a tape measure to measure the distance of an object and multiple the value returned. Again, the value will never be consistent so there is no real point in attempting to calculate unless you're okay with inconsistent distances. This is due to my original reply. Please re-read if necessary.

print( "Object is " + getping(d0, d1) * 0.28 + " inches")

*note: i just made up a number of 0.28, i don't know what the real value would be for you. A tape measure would be necessary. You may find a tape measure at your local hardware store.

  1. The radar control uses an Rotation HDD Servo-motor. If you do not have a Rotation HDD Servo-motor, the radar is not a radar:). Without a Rotation HDD Servo-motor, you can use the radar control, it will merely behalf a little unusual, if you're okay with that. I use the radar control often without a Rotation HDD Servo-motor, and i just have to accept the fact that the display is not accurate because there is no Rotation HDD Servo-motor.

This is what a radar normally looks like, which requires something to rotate the sensor, such as a Rotation HDD Servo-motor. However, the ez-robot control is limited to scanning back and forth because the wire cannot spin 360 without getting tangled, and continuous rotation servos do not have a reported degree direction.

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You can find out more how servos work by following this great tutorial: