Intelligent Headlamp Levelling : Thesis work at Scania CV AB

Abstract: Illumination of the road environment plays an important role for the night-time vision of the driver and in general road safety. The purpose of this thesis is to develop a proof of concept that can measure the vertical angular displacement of a truck headlamp relative to the road. This was achieved by gathering customer needs and establishing a target specification. Two concepts were considered to have the potential to satisfy the target requirement values and were selected for further development, one based on accelerometers and the second based on an Inertial Measurement Unit. Prototypes were developed and built to test and evaluate the concept against the target values. Once a concept was chosen, a reference plane was introduced to complete the concept which enabled testing and simulations of a variety of scenarios that a truck faces when operating on roads. The final product is based on digital accelerometers controlled via a microcontroller. The result of the final testing and simulation shows that the developed concept can measure an angular displacement with a mean inaccuracy of ±0.051◦ regardless of the slope of the road. This inaccuracy corresponds to ∼ 14% of the required tolerance according to a proposed revision of the current UNECE-48 regulations, which gives a tolerance leeway of ∼ 86% for the rest of the control system.