Week 5 Bending of iPhone
Aim: In this simulation we will be looking in detail at the stress and strain generated in an IPhone as it is bent as well as the deformation and the same values for a different position of application of force.
We begin the simulation by inspecting the geometry in space claim and reducing the number of faces on the fingers by merging them together so it can run on the student version.
Following this we open the mechanical module and assign the frame of the body with Al Alloy NL, the display as glass for which we have mentioned the characteristics in the engineering data section and the insides which we have assigned as polyethylene.
Simulation Setup :
We establish the contacts such that the contact between the display and the frame is bonded and all other contacts are frictionless. We also have to delete 2 contacts which are between 2 Fingers.
Following this we create joints at all the fingers with all but the thumbs being fixed to ground and the 2 thumbs being translational joints.
We add a face sizing between the back of the frame and the 2 faces of the thumbs which are in contact with the frame of 4mm.
The simulation is conducted over 8 steps with direct solver, constant stabilization with energy dissipation factor of 0.1, and all the output controls flipped to On.
We proceed to add a fixed support to the insides of the phone and constrict the movement of the frame in X&Z Axes.
The next step is to provide the displacement to the thumbs which goes up from 0-8 and back down to 0 over 8 steps.
For the 2nd Case we maintain the exact same setup but change the position of the Thumbs by 10mm and 22.5mm in the X&Z Axes while merging the faces in Spaceclaim.
Results & Conclusion:
The deformation experienced in Case 1 is 6.28mm
The deformation experienced in Case 2 is 4.88mm
Case 2 experiences lower deformation as the force is applied closer to the center of mass of the body and is directed along the entire structure more evenly as compared to Case 1.
The overall structure has a factor of safety averaging close to 15 with an average life between 10^7 and 10^8 cycles.