Analysis of the procedure for suspension evaluation of civil armoured vehicles: reliability and safety driving criteria

Abstract

sis of the procedure for suspension evaluation of civil armoured vehicles: reliability and safety driving criteria.Abstract: The present study exposes an analysis of the suspension system technical state evaluation for civil vehicles that have been subject to armouring processes. Such evaluation is performed through a mechanised revision established by state regulation and is based on the method defined by EuSAMA. The development of this analysis focuses on establishing the existing relation between the ballistic resistance integrated to a vehicle and the dynamic effect exercised for the modification of its mass, according to two reliability/safety driving measurement criteria: (i) tyre-road adhesion index and (ii) tyre excitation phase angle. The study proposes new elements to the current procedure established to evaluate the suspension of civil armoured cars considering the two measurement criteria, which can be acquired by a standard commercial suspension tester machine.

Effects of Using Various Methods for Car Shock Absorbers Diagnostic Tests

“…• despite large changes of shock absorber viscous damping, there is a fairly small range of diagnostic parameter variability (even for the lowest level of sliding friction in the suspension does not exceed 35 percentage points); • even with very high damping in the rear suspension, it is difficult to get EUSAMA indicator values greater than 50%; • the growth of the sliding friction in the suspension system by 180 N could cause here the final test results to be overestimated by as much as 30 percentage points. When the reliability and usefulness of the phase angle method proposed in [3,11,16] and [17] was assessed, the following was observed:…”

“…Predominantly, "forced vibration tests" are used for this purpose [3,4,6]. A similar approach can be found in [8,9,11] as well as in [12,13,14] and [16,17]. At present, efforts are made in Europe to adopt an identical (standard) vibration excitation method for all the shock absorber testers.…”

“…6 mm, as it is in the case of the EUSAMA machines [2,4,12] (see also [18,19]). Unfortunately, such testers, which are most popular, suffer from a major drawback: the final test result strongly depends on tire inflation pressure [13,14,15], sprung mass [11,13,14], sliding friction in the suspension system [18,19], test conditions, and tester characteristics [10,16].…”

“…In consideration of the above, the authors decided to verify the reliability and usefulness of the phase angle method [3,11,16] (see also [17]) and the half power bandwidth method (HPBM) [4,6,7] in relation to the classic EUSAMA test, the newer methods are based upon. This was the main objective of this work.…”

Analysis of Driving Safety Criteria Based on National Regulations for the Suspension Systems of NGVs

“…1), denoted adhesion index 1 A(), which is critical to basic safety, it is therefore very important that the levels of A() are measured. In the case that a vehicle has a reduced level of adhesion, then it has a high potential driving accident due to the skid eff ect (Robinson, 1997;Buczaj et al, 2007;Martinod et al, 2013). NGVs incorporate an extra-mass m a , to the design mass of the vehicle m v , and causes an increase in the total mass of the vehicle m t , where m t = m v + m a , and A()μm t .…”