Reproduction of real-world road profiles on a four-poster rig for indoor vehicle chassis and suspension durability testing

Abstract

Indoor testing should reproduce the real-world environment in order to be effective. In this article, an efficient methodology to reproduce road profiles on a four-poster rig is presented: such a method includes a complex rig control strategy based on an iterative process. Road profiles come from a purposely designed set of sensors fitted on the car which remains the same regardless of the vehicle or surface type. Particular stresses such as speed humps, potholes and manholes can be reproduced as well. Since there are no previous similar studies, a validation is provided by comparing road and rig data streams and using the maximum absolute error and root mean square error as performance indexes. Results show that the rig is able to reproduce road profiles and the related inputs to the vehicle successfully; hence, the method is reliable and effective.

Correlation between Numerical and Experimental Structural Resistance of a Safety Relevant Aluminum Automotive Component

“…The mechanical properties were lower in areas located close to high thickness zones (σ p0,2 = 117 ± 3 MPa, σ m = 234 ± 25 MPa, A% = 6.4 ± 3.8%) than both those calculated for areas distant from these zones (σ p0,2 = 134 ± 5 MPa, σ m = 266 ± 20 MPa, A% = 4.7 ± 1.8%) and for those measured in samples cast separately from the same die (σ p0,2 = 134 ± 7 MPa, σ m = 258 ± 5 MPa, A% = 5 ± 0.9%). More detail regarding the characterization and the results can be found in a previous work of the authors [8]. These data were also in agreement with the nominal range of mechanical properties for this alloy (σ p0,2 = 120-150 MPa, σ m = 250-290 MPa, A% = 5-11%, σ FAF = 89 MPa) [25].…”

“…The variability in mechanical resistance was related to the different thickness and the consequent solidification speed of the various areas of this high-dimensional component. Indeed, the mechanical characterization of the prototypes, detailed in [8], was carried out both for samples machined out of the components and on samples cast separately by die casting in different areas in order to evaluate the real properties of the cross beam in detail. At least four measurements were taken for each condition, and the average value is reported for each.…”

“…The difficulty arising from the substitution of traditional metals (i.e., steel, cast iron) with lighter ones (i.e., aluminium alloys) in this class of vehicles is related both to the elevated operating loads, which imposes strict requirements on resistance and stiffness, and to the lower eligible costs. Of course, the preservation of the safety and performance levels required by automotive standards is a very important aspect [8,9] that needs to be carefully evaluated when reducing component weights. This is particularly true for safety-critical parts such as the suspension cross beam, control arms, and brakes, failures in which result immediately in the loss of vehicle orientation [10].…”

Design of a Road Simulator for Motorcycle Applications

“…The four-poster itself features the possibility to reproduce any road surface accurately, starting from a real-world acquisition, and then using a complex iterative deconvolution process [18][19][20][21]. This controller is separate from the one employed to "play" standard waveforms and used to perform standard tests as reported in Section 3.1.…”

Experimental and Numerical Study of an Automotive Component Produced with Innovative Ceramic Core in High Pressure Die Casting (HPDC)

“…The current use of castings for aluminum chassis structural applications is limited to a niche market for high performance cars. Nevertheless, automobile weight reduction is currently becoming an essential requirement to improve vehicle performance [1] and reduce fuel consumption and harmful emissions [2][3][4][5][6][7]. The environmental importance of reducing the weight of these aluminum components has been recently demonstrated by means of a life cycle assessment tool [8][9][10].…”