Research On Overlay Technology Of Vehicle-mounted Flexible Electronic Structure

New energy vehicles have the characteristics of whether they have exhaust emissions and low vehicle costs,which are welcomed by everyone.The use of functions such as automatic driving and active and passive safety has increased the proportion of electrified equipment on new energy vehicles.At present,there has been a lack of breakthroughs in the weight control field of automotive power batteries,and the need to accurately collect battery voltage,temperature,current and other information inside automotive power batteries will inevitably lead to intricate internal wiring.Using flexible FPC instead can reduce weight and assembly processes.The working environment of flexible electronic circuits is narrow,tortuous,and even space-folded.Covering flexible electronic circuits on irregular curved surfaces can reduce space occupation.Therefore,covering is the core link.The overlay of flexible electronic circuits is a process of elasto-plasticity and large deformation.The results obtained by ordinary CAD-based geometric mapping methods are inaccurate.Therefore,a forming algorithm with better calculation accuracy is required.At present,the forward simulation incremental method of the general-purpose finite element software in the market needs to go through multiple process simulations,which has the problem of long calculation time and is not suitable for use in the field of flexible electronic circuits.Therefore,starting from the preparation process of flexible electronic circuits,reverse forming The finite element method becomes a better choice.At present,commercial software has implemented a one-step inverse forming algorithm,which has good solution speed and accuracy for general body parts,but the flexible FPC structure is more complex,and the market finite element solvers have poor calculation robustness and poor solution accuracy.Can’t even calculate the problem.Therefore,in order to solve these problems,the research content of this paper is as follows:(1)This paper proposes a rapid construction method for the intermediate configuration surface,which is obtained by ignoring the initial stress and initial strain of each nonlinear iterative analysis step.Because some flexible electronic structures have final configurations and some do not,the rapid construction method of intermediate configurations proposed in this paper can solve this problem.It not only provides an intermediate configuration for the overlay solution frame,but also provides a configuration close to the final configuration for the structure without an intermediate configuration.This paper verifies the validity of the construction method and lays the foundation for the multi-step inverse flexible electronic structure overlay solution framework.Data calculation examples show that the intermediate configuration constructed by the rapid construction method of intermediate configuration proposed in this paper is ideal compared with the true solution,and meets the requirements of use.(2)This paper proposes a multi-step inverse-based flexible electronic structure overlay solution framework.The large deformation forming algorithm in the stamping field can be used in this field to realize the overlay on the three-dimensional undevelopable surface.The long calculation time and even non-convergence problems exist in related calculations.The shape of the flexible electronic structure is complex,and there are a lot of problems such as negative angles in the cover shape calculation process.This paper first cuts the parts with negative angle problems,then uses the one-step inverse method to flatten them separately,uses the FPC "stitching" algorithm of this paper to stitch,and finally obtains the complete flattened configuration after iteration.In order to ensure accuracy,through continuous mapping and flattening,the displacement difference of the same node is compared.When the difference is within the error range,it will converge.Otherwise,continue to iterate,and finally get an accurate FPC space configuration.In this way,the configuration is changed from iterating in space to iterating on the plane,which simplifies the calculation process.In summary,this solution framework combines the advantages of the forward simulation incremental method and the one-step inverse forming algorithm,which saves time and ensures calculation accuracy.