Static Compliance Measurement as a Method of Assessing Damage

It is not uncommon in motorsport for a team to chase a chassis setup throughout a race weekend, changing many different suspension settings, yet not getting consistent response from the chassis. In at least some of these cases it has been later determined that these inconsistencies stemmed from either chassis damage or fastener loosening, leading to a decrease in chassis stiffness. The current research investigates a method for quickly and accurately measuring the torsional stiffness, or static compliance, of a racecar chassis and suspension at various stations along the length, which can be utilized in the paddock area. When compared to baseline measurements of a newly assembled racecar, the post-race static compliance of the vehicle can be used to reveal the length-wise region of new damage or softening of components. Such measurements can indicate delamination of a monocoque chassis, damage, or fastener loosening in locations such as at clip interfaces, or even damage at suspension brackets. Measurements demonstrate the sensitivity of this technique to loosening of braces and brackets, and thus, demonstrate that by periodically checking the static compliance of the chassis, it may be possible to diagnose problems with the racecar and, more importantly, localize the problem. This means teams can spend more time on the track and less time in the garage disassembling the car.