U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
REPORT |
This report is an archived publication and may contain dated technical, contact, and link information |
Publication Number: FHWA-HRT-07-040 Date: October 2011 |
Publication Number:
FHWA-HRT-07-040
Date: October 2011 |
The following suggestions are not a part of the formal protocol, but they have been found to be helpful in the success of the procedure.
Note: For accurate results, it is important that the reference load cell be zeroed with the FWD load plate in the raised position. Also, the signal conditioner excitation and gain must be set carefully to the levels at which the reference load cell was calibrated, as indicated in the WinFWDCal prerequisite information during setup.
Note: The goal is to have the sensors centered on the accelerometer and to invert them uniformly in the second trial. If additional calibration trials are needed, they should be performed in sets of two using the positioning shown in the table.
Note: For trial 1, stand behind the stand facing the FWD load plate with sensors D1, D3, etc., in the left column. For trial 2, rotate the stand vertically on the ball swivel so the column with sensors D1, D3, etc., is on the right.