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Unread 23-02-2016, 03:53
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Re: Ultrasonic Rangefinder giving inconsistent values

Quote:
Originally Posted by rohinb View Post
Hi all,
Our team is using an ultrasonic rangefinder (link here: http://www.maxbotix.com/Ultrasonic_Sensors/MB1023.htm) and we have been having trouble getting consistent values from it. It seems to randomly switch from accurate values to unreasonable values (with an error anywhere from 20cm to 70cm) for the voltage and the value (we are using java and the methods getValue(), getAverageValue(), getVoltage(), getAverageVoltage()). As of now we are simply printing these values to try to find a way to make them consistent. We are aiming it at a hard surface (a metal plate or a wall) and are aware of the 30cm deadzone. Does anyone have any ideas? Any help would be appreciated.
Thanks,
Rohin Bhushan
Team 3482
Ultrasonic sensors have a 'cone' of detection. Some of them are quite wide. Do you have more than one sensor running? Do you have anything near the cone of detection? Is the sensor extremely close to the ground?

Have you set a gain? The sensor returns a value that is linearly proportional to the distance, but you need to use a gain to make it accurately report. I.e. - is it consistently wrong? Or is the distance inconsistent.

We've never had good luck with the maxbotix sensors.