Ultrasonic Rangefinder giving inconsistent values

[rohinb]

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