Optimum Damping and Spring Stiffness of Semi-Trailer Truck for Minimizing Unwanted Body Motion Due to Road Irregularities Using Taguchi Method

The suspension system in an automotive vehicle is the interface between the vehicle body to the chassis and the road through the wheels. The main purpose of suspension is to absorb shock and vibration when the vehicle overcoming road irregularities. However, there are still issues where passive suspension is still unable to absorb maximum shocks in large vehicles for a pleasant ride when riding on an irregular road surface. This condition can cause a major risk to the driver which will cause the vehicle to experience rollover as the road bumps can cause instability to the vehicle. Therefore, the goal of this study is to determine the optimum spring constant, damping, toe angle and camber angle of the vehicle which allows them to optimally absorb the vibration due to road irregularities. The Trucksim software is used in this study to analyze the vehicle’s vertical acceleration mainly at different spring constants, damping, toe and camber angle of the truck. Methodology used in optimization of suspension system of the 3-axle semi-trailer truck subjected to road excitation is by using Taguchi method. Using Root Mean Square (RMS) measurements of vertical acceleration, the effect of suspension stiffness and suspension damping alongside with the toe and camber factor of the vehicle on vertical acceleration is investigated. The data produced from this study can be used by researchers to improve the driving behaviors and driving characteristics of heavy vehicles.