Inclinometer

POSM Inclinometer Controls

The Inclinometer Controls allow POSM to record the angle and percent grade of the camera as it makes it way through the pipe. Currently, with the RST Inclinometer, POSM will record an Observation ever 1/10 of a foot or every 560 milliseconds. It will take only one reading per 1/10 of a foot. If communications with the Inclinometer unit are lost, POSM will try ten times to reconnect. If unsuccessful, it will turn the Inclinometer off and give a warning to the user. In order to turn the Inclinometer on you must check the Inc On Box.

Inclinometer Calibration

At a minimum the Inclinometer should be recalibrated every time the wheels or tracks are changed on the camera. There are two methods to calibrate the Inclinometer in POSM.
The first method requires the camera be placed on the ground. At this point press the “Set Offset 1 Button”. Then rotate the camera 180 degrees (for example if the camera head was facing you, the back of the tractor would be facing you after you turned it around) and press the Set Offset 2 button. An offset degree measurement will display below the Set Offset Buttons. This is the offset POSM will use to create a correct angle measurement of the pipe.

Setting Offset 2

To reset the offset distance to zero place the letter “A” in the offset degree measurement box and press the
“Set Offset 2” button.

Reset Inclination Offset with an “A”

The second and more precise method to calibrate the Inclinometer is to use the “Zero Inc” button. This button will communicate with the inclination device in the camera to set the new zero level in its firmware. Make sure that the Offset Value has been set to zero by placing an “A” in the Offset box and pressing the “Offset 2” button.
To use the “Zero Inc” button, the camera and tractor must be placed on a perfectly flat surface. This is best done with a bubble surface level and a flat board with adjustable legs.

3 Leg Adjustable Table with a Bubble Surface Level


Calibrating a Camera on a Skid Calibrating a Crawler

After adjusting the feet so the board is level, place the camera and tractor on the board. Let the camera sit for a few moments so the Inclinometer can come to complete rest, then press the “Zero Inc” button. Press “Yes” to the conformation window to continue or “No” to stop.

POSM “Zero Inc” Conformation Window

When the Zeroing has completed, a “Done” window will appear. Press “OK” to continue.

Zeroing has completed

Inclination Performance

Proper use, setup and calibration of the inclination system can produce smoother more accurate plots. In order to produce a correct representation of the pipe, POSM needs as many points as possible. Cleaning the line to remove grease, rocks, sand and other debris will help the camera stay on the pipe walls and keep the camera from jumping up and down. Running slowly down
the line will allow the software to collect more points and it will keep the camera from jarring which can throw off the sensor. Use of a camera skid in the line is recommended for the highest
quality data. A crawler (tracks) motor would be recommended if skidding is not available or
possible. Wheeled tractors can produce acceptable results but have a tendency to throw out more data. The key to the most accurate data collecting is calibrating the camera correctly and running slowly to collect more data points.