Optimization of Aluminum Sleeve Design for the tow eye Durability Using DFSS Approach 2023-01-0092

The automotive industry is moving towards larger SUVs and also electrification is a need to meet the carbon neutrality target. As a result, we see an increase in overall gross vehicle weight (GVW), with the additional weight coming from the HV battery pack, electric powertrain, and other electrical systems. Tow-eye is an essential component that is provided with every vehicle to use for towing during an emergency vehicle breakdown. The tow-eye is usually connected to the retainer/sleeve available in the bumper system and towed using the recovery vehicle or other car with towing provision. Therefore, the tow-eye should meet the functional targets under standard operating conditions. This study is mainly for cars with bumper and tow-eye sleeves made of aluminum which is used in the most recent development of vehicles for weight-saving opportunities. Tow-eye systems in aluminum bumpers are designed to avoid any bending or buckling of the sleeve during towing for whatever the GVW loads. So that the vehicle doesn’t face any tow-eye system failure, which would prevent another car from towing the breakdown vehicle and would need special roadside assistance to take it for servicing. This paper uses the Design For Six Sigma (Taguchi Method) approach to identify the potential control factors (from the benchmarking study) to optimize the tow-eye sleeve to withstand higher GVW load without functional loss.

Furthermore, this approach proved that the selected optimum design is less sensitive to noise factors such as aluminum property variation, bumper beam thickness variation, and load direction variation. The learnings from this paper will help to reduce the development time and cost by implementing the robust sleeve design in the early stage of the program.