The objective of this project, carried out in 2001, was to investigate the design of an operational scale device for testing the 'road-friendliness' of heavy vehicle suspensions. This includes an estimate of the cost of manufacturing the device, adapting an existing facility (such as a vehicle testing station) for the operation of the suspension tester, and the running costs associated with the testing device.
Two testing regimes were considered:
As part of the design, a review of procedures and devices used to test for road-friendliness overseas was conducted.
The investigation estimates costs of constructing, maintaining, and operating a facility for type-approval or in-service compliance testing of heavy vehicle suspensions, for the purpose of determining their natural frequency and damping ratio.
General arrangement drawings of the device are provided along with the cost estimates of the facility. The initial facility cost is estimated to be $146,700. The annual operating cost is estimated to be $96,000. It is expected that these costs could be recovered through a combination of type-approval testing, with a cost of $600 per vehicle tested, and in-service compliance testing with an estimated cost of $40 per test. This is based on an estimated average time for a type-approval test of eight hours (one day) and an estimated average in-service compliance test time of 30 minutes.
The cost of suspension testing using the test and apparatus outlined in this report is expected to be substantially lower than the costs of road-friendliness testing facilities in Australia and the United Kingdom.
Keywords: cost, heavy vehicle, New Zealand, road-friendly suspension, suspension, suspension testing, toads, testing, traffic, transport, vehicle