Digital konstruktion samt verifiering av hjulupphängning till JU Solar Team´s solbil 2019

Sammanfattning: There is a need to improve the JU Solar Team's new solar cell powered electric car's driving capabilities for the Bridgestone World Solar Challenge 2019. Partly to improve the car's safety and the ability to meet the competition requirements, but also to minimize effects that contribute to increased rolling resistance. The work is carried out at Jönköping Institute of Technology with support from ÅF Automotive in Trollhättan. The work aims to parameterize driving characteristics with engineering requirements, evaluate how the rolling resistance can be minimized, how negative driving characteristics can be minimized and a weight comparison with wheel suspension from 2017. This is the basis for the construction of the 2019 wheel suspension adapted for new body designed and manufactured in parallel with this work. The study includes performed measurements of the side force impact on steering angle change and camber change, calculation of load case, concept generation and evaluation, computer-aided strength evaluations. The results of the survey show great weaknesses in the 2017 solar car. In the case of an applied side force in the front wheel, a large wheel angle change occurs. This is largely due to under-dimensioned steering arms and the geometric design of the points. The influence of the side force on the steering angle has theoretically been reduced by at least 44% verified in CAD environment. In addition to this improvement, the entire wheel suspension system's attachments and sub-components are stiffer, which should contribute to an even greater improvement. The study also shows that the steering angle was insufficient to meet the competition requirements, which could be improved by 21.2% greater steering angle on the wheels. The spring and damper's operating ratio in comparison with the wheel has also been evaluated and has been able to be increased from 31% to 51.5%. This leads to reduced forces on the link arms and body by 20.5% during the same external load case. The study is limited to evaluating the hard points of the wheel suspension as well as the strength and design of the link arms, steering arm, suspension and damping attachment.