From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Engineering test procedure for skid pad testing.
| Identifier | ExFiles\Box 155\4\ scan0057 | |
| Date | 30th April 1940 guessed | |
| E.R. 51. Skid Pan File 1322 SCHEDULE No. 206 VAUXHALL MOTORS LIMITED SHEET No. 1 ENGINEERING TEST PROCEDURE CHASSIS SECTION SUBJECT SKID PAD TEST PROCEDURE. (a) Transit Theodolite. (b) Theodolite stand with attachments. (c) Front wheel indicators. (d) Front wheel indicator supporting pillars and attachments. (e) Steering wheel indicator. ATTACHING INSTRUMENTS TO CAR. PAGES 7, 8 and 9. It is important to see that the front wheel indicator supporting pillars are as nearly as possible parallel to the pivot pin otherwise there will be a geometrical error resulting in unequal movements between wheels and indicators. The pillars themselves are clamped to the front wings in such a position as to fulfil as nearly as possible the above conditions and are then inter-connected and supported by means of the cross tube. The steering wheel indicator is clamped to the spokes of the steering wheel and a stiff pointer is attached to the dash or any other convenient and rigid part of the car in such a way that "Zero" on the steering wheel indicator corresponds to "Zero" on the front wheel indicators. The Theodolite stand is fastened in front of the rear seat in the centre of the car in such a position that the centre pole of the skid pad can be sighted by the Theodolite through one or other of the side windows. CALIBRATE STEERING INDICATORS. With car in the straight ahead position both front wheel indicators should be set at Zero. A small Zero error as between car direction and wheel indicators is permissible as the true Zero for each direction of turn is evident on plotting results and a suitable correction can be made if necessary. Zero errors as between the two indicators should be kept as small as possible. On cars with independent front suspension the steering angle at Zero lateral acceleration will generally be above the Ackermann angle because (a) the front wheels roll with the car; (b) there is "sticktion" in the suspension, in roll. Signed ......................... Dated .......................... Approved ....................... | ||