Calibrating the Pitch and Roll

You need to calibrate the pitch and roll of the sensors when they are placed in the sensor pockets.

Before you begin

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

About this task

The 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.

If you do not know the pitch and roll offsets, doors need to be taken out and placed on the ground in order to calibrate the pitch and roll.

Procedure

  1. If you already know the pitch and roll offsets, go straight to step 4.
  2. Prepare the doors:
    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.
  3. Insert the sensor in the pockets on the doors.
  4. Open Mosa2 application.
  5. Activate and deactivate the water-switch to connect the sensor to Mosa2 via a wireless signal.
  6. Click the tab Pitch and Roll.
  7. Click Pitch and Roll Calibration, then:
    1. If you already know the pitch and roll offsets, select Manual, then manually enter the offsets.
    2. If you do not know the pitch and roll offsets, click Auto Calibrate. Offset values change according to the position of the sensor on the door.
  8. Click Save.
  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.
    1. Roll

    2. Opening angle: 25-40°

    3. Pitch
  10. Click Apply and make sure there is a green check mark .