| 摘要 |
Apparatus for measuring friction characteristics of a vehicle-travelled surface comprising a wheeled vehicle having a test wheel assembly pivotally suspended therefrom by a parallelogram suspension arrangement. The test wheel assembly includes a test wheel carried by a drive shaft which is driven at predetermined slip by a differential coupled to the vehicle wheels. A gear chain extends from the differential to the drive shaft through a housing which forms one arm of the suspension. The second arm is formed by a rod which extends from the differential to one section of a two-axis strain gage wheel force transducer at the test wheel assembly. The differential is suspended by parallel struts from the vehicle frame. A positive displacement pump is coupled to the differential for placing a film of water beneath the test wheel having a thickness which is independent of vehicle speed. The pump and test wheel are clutch driven. |
