Document ID: chunk:federal_register_of_legislation:F2024C00147:body:0:p47
Version: federal_register_of_legislation:F2024C00147
Segment Type: other
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Character Range: 162958–165776

of view of the camera. Use the following working steps for determination of the minimum mounting height.

       1.4.1.1. Step 1: Draw the intended field of vision on ground.

       1.4.1.2 Step 2: Place the camera above the field of vision in such a way that the camera is viewing the field of vision. The lateral position shall be in accordance with the intended mounting position at the vehicle.

       1.4.1.3. Step 3: Change the height of the camera above ground in such a way, that the field of vision displayed on the monitor covers an area at least as large as the field of vision. Furthermore, the field of vision display should encompass the entire monitor screen.

       1.4.1.4. Step 4: Measure the height between camera and ground which is the minimum mounting height. Report the result value.

       1.4.2. The value of the maximum mounting height is different for different viewing distances as the displayed object size varies with the mounting height. Use the following working steps for determination of the maximum mounting height:

       1.4.2.1. Step 1: Determine the minimum width bmin of the critical object displayed on the monitor for each viewing distance.

       Where:

       r: viewing distance in mm

       bmin:  minimum width of the critical object displayed on the monitor in mm

       1.4.2.2. Step 2: Place the critical object inside the drawn intended field of vision in a position at which the distance between the critical object and the camera is largest. The illumination conditions shall be in such a way that the critical object is clearly visible on the monitor.

       1.4.2.3. Step 3: Select the first value of the possible viewing distances.

       1.4.2.4. Step 4: Change the height of the camera above ground in such a way, that the residual width B of the object displayed on the monitor is equal to the minimum width allocated to that viewing distance.

       B=bmin

       Where:

       B: residual width of the object displayed on the monitor (which is "b" in cases without smear and "b – s" in cases with smear) in mm (see paragraph 1.1. General)

       1.4.2.5. Step 5: Measure the height between camera and ground which is the maximum mounting height allocated to that viewing distance. Report the result value.

       1.4.2.6. Step 6: Repeat the aforementioned steps 4 and 5 for the other viewing distances.

         APPENDIX b – UNECE R81
AGREEMENT
CONCERNING THE ADOPTION OF UNIFORM CONDITIONS OF APPROVAL AND RECIPROCAL RECOGNITION OF APPROVAL
FOR MOTOR VEHICLE EQUIPMENT AND PARTS[*]

done at Geneva on 20 March 1958

________________

Addendum 80: Regulation No. 81

Date of entry into force as an annex to the Agreement: 1 March 1989

Incorporating all valid texts up to:
Supplement 1 to the original version of the Regulation -