Creating Transport Vibration Simulation Profiles from Vehicle and Road Characteristics

Abstract

It is today generally accepted that to carry-out realistic transport simulation trials, field data must be acquired from vehicles travelling on the actual route(s) to be used for a particular distribution environment. This approach requires time, effort, access to data recording equipment as well as the necessary expertise to analyse the collected data. Often, this is out of reach of smaller operators who want a reasonable approximation without the time and expense. Currently, the only available option is the adoption of generic test spectra and levels that have been shown to be approximate representations of distribution environments. This paper discusses an alternative and practical method that uses some knowledge of the dynamic characteristics of various vehicle types along with an assessment of the types of roads (road roughness) to be encountered along a particular route. The method exploits the fact that the spectral characteristics (power spectral density) of road profiles are well known. The paper shows how this road surface elevation spectral function is combined with a numerical model of a particular vehicle type and speed to produce a target vibration power spectral density suitable for vibration test systems. One added benefit is that the method is capable of calculating the variations in root mean square levels of the response vibrations. This is presented as the root mean square distribution which, when coupled with the target power spectral density, can be used to synthesize realistic random vibrations that bear statistical similitude with real, field vibrations.

Measuring the mechanical and climatic conditions encountered by palletized products in handling and transport

“…A critical note dealing with the procedure for interpreting signals was cited in [51], where was judged the semi-stationary simulation (RMS=cost) as not properly reliable, as [44] and [48]. Moreover a PSD manipulation involved a re-arrangement of a real environment conditioned, and an ISTA PSD are not properly reliable.…”

“…Moreover a PSD manipulation involved a re-arrangement of a real environment conditioned, and an ISTA PSD are not properly reliable. The same [51] also proposes a method to release the absence of data recorder, but which it requires to know the vehicle response.…”

Consideration on road transport vibration simulation techniques for packaging testing purposes

“…This is why it is of utmost importance to simulate these stresses before transportation as exactly as possible. For the time being no totally perfect solution is available for this issue [2]. Over the last 50 years, the vehicle vibration simulations developed from simple mechanic instruments to state-of-the-art computer controlled vibration tables [3].…”

On-the-road Measurements to Establish the Dynamic Characteristics of Transport Vehicles

“…6 The approach makes use of known road roughness, vehicle dynamic characteristics and a trip schedule that consists of the estimated operating speed and duration travelled over each road. The authors stated that this approach provides a viable alternative to simulate realistic transportation vibration without having to undertake extensive measurements.…”