Calibrating the Pitch and Roll

You need to calibrate the pitch and roll of the sensors when placed on the trawl doors.

Before you begin

Tip: Some trawl door manufacturers measure the pitch and roll offsets themselves and write them on the doors. Check on trawl doors.

About this task

A sensor pocket is usually welded to the door at a 15 to 20 degree vertical angle. This means that when trawl doors are vertical, the sensors will already have a pitch angle and maybe a roll angle. You need to calculate these angles and offset them in order to have 0° of pitch and roll when doors are vertical.

Calibrating Automatically

Procedure

  1. Remove all rigging, shackles and attachment points from the doors.
  2. Remove the net gear attached to the door.
  3. Using a crane or forklift, place the door on a flat surface, such as a dock or similar location.
  4. Using the necessary rigging, hang doors with angles as close to 0 degree as possible on the vertical and horizontal plane. Use a carpenter level to help you.
  5. Insert the sensor in the pockets on the doors.
  6. Connect the sensor to the Dock or Configuration Cable to connect to Mosa2.
  7. From Mosa2, go to Measurements page and click in Motion.
  8. Check on the bottom of the window that the pitch and roll of the door are close to 0 degree.
  9. From Opening Angle, enter the angle between the door and the sensor (horizontal plane) in degrees. If you do not know the angle, ask the manufacturer for the angle of attack. If you cannot know the angle, you can put 35° but be aware that a wrong angle impacts pitch and roll measurements.
  10. Click Calibrate.
    The sensor is calibrated.