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The need and dependency on objective measurements are increasing rapidly across all industries for reliable and faster data for product validation, and the automotive industry is no different. Objective measurements are becoming increasingly popular than subjective evaluation as they offer objectivity and repeatability. Typical industry practice for structural validation is to acquire the vehicle responses, viz. spindle accelerations, wheel displacements, wheel forces, speed, strain at a few critical locations, and others as per the requirement. Vehicle responses are usually acquired on specific road surfaces, test tracks, and proving grounds. Prior to the tests or measurements, the vehicles are configured as per the company's recommendation, such as tire pressure, camber angles, engine oil, coolant oil type and quantity, load, and load distribution, to name a few. The test vehicles with which these measurements are carried are usually only with these vehicle settings.

Vibrational fatigue is a metal fatigue caused by the forced vibrations which are purely random in nature. The phenomenon is predominantly important for the components/systems which are subjected to extreme vibration during its operation. In a vehicle, an engine is the main source of vibration. The vibrational fatigue, therefore, plays a key role in the deterioration of engine mounted components. Multiple test standards and methodologies are available for validating engine mounted parts of an automobile. These might not be appropriate in the case of an off- road vehicle as the vibrational exposure of engine mounted components of an off-road vehicle is entirely different. In the case of an off-road vehicle, the engine mounted components are subjected to a comparatively higher level of vibration for a longer duration of time as compared to the passenger cars.

Twist beam is a type of suspension system that is based on an H or C shaped member typically used as a rear suspension system in small and medium sized cars. The front of the H member is connected to the body through rubber bushings and the rear portion carries the stub axle assembly. Suspension systems are usually subjected to multi-axial loads in service viz. vertical, longitudinal and lateral in the descending order of magnitude. Lab tests primarily include the roll durability of the twist beam wherein both the trailing arms are in out of phase and a lateral load test. Other tests involve testing the twist beam at the vehicle level either in multi-channel road simulators or driving the vehicle on the test tracks. This is highly time consuming and requires a full vehicle and longer product development time. Limited information is available in the fatigue life comparison of multi-axial loading vs pure roll or lateral load tests.

Suspension system is one of the most important systems in an automobile and the failure in the sub systems or parts would prove catastrophic. A semi-trailing arm (STA) suspension is an independent rear suspension system for automobiles where each wheel hub is located only by a large, roughly triangular arm that pivots at two points onto the chassis or the body. STA usually is subjected to three directional loads viz. vertical, longitudinal and lateral in service. The conventional methodology of validating the system is by applying multi-axial loads or by road load simulation consuming significant amount of time. In this paper an attempt is being made to validate the damper mounting pins by reproducing the damper loads locally instead of validating the entire system. STA was strain gauged at the critical locations and was mounted onto the vehicle.