ACF - Aligned C-Frame

ACF is a new type of C-frame(tool holder) for different types of joining applications such as self piercing riveting(SPR) and clinching. The lightweight aligned C-frame (ACF) increases mobility and productivity and is well suited for automated processes.The ACF is designed using a combination of modern finite element structural optimisation. Below an example of a conventionel C-frame is showed together with an illustration of different occuring process errors


d - misalignment, a - angular error, x - die movement u, y - die movement v

       bad joint                 good joint

Optimisation of an ACF

First step is formulate the optimisation problem, i.e which objective, constraints and design space we have to deal with.
Second is to design an inititial suggestion and create FE models in which all necessery data for the optimisation formulation is calculated and written to files. In this case it's enough with one FE model.


Initial FE model, deformations amplified x10

Optimisation formulation


Definition phase

1. Include analysis
2. Define design variables
3. Define objective function
4. Define constraints

The mesh morphing phase

Import model to the morpher
Create morphing geometry (grey)
Add design varibles to morphing geometry and link to nodes
Testing, some selected variables varies between it's limits

Solution phase

Start executions
and follow how the optimisation proceeds

Postprocessing phase

Optimisation history, deformations amplified x10 and geometry changed through out optimisation. The die movement (objective function) is very small and all constraints was feasible after the optimisation.


Final FE model, deformations amplified x10

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