Week 5 Bending of iPhone
Objective: To perform a bending test on I phone and its Observations and results were analysed. The Analysis is based on 2 bending positions. Furthermore, its directional deformations, stresses, strain and life is also evaluated.
Case 1: The bending position is at the edge of the casing.
Case 2: The bending point is placed at given position X= 22.5 mm & Z= 10 mm.
1. Geometry:
i. Case 1:
ii. Case 2:
2. Material data:
Display - Glass
Casing - Aluminium alloy NL
Inside - Polyethylene
fingers - Structural steel.
3. Case Set up and settings.
i. Connections:
a. Contacts
The display and casing are provided with a bonded contact.
Fingers to the phone is given a frictionless contact.
b. Joints
Fingers are given a body to ground fixed joint. Translational joints are provided to the thumb, where the bending initiation is given.
ii. Mesh:
Face sizing of element size of 4 mm is provided for the contact regions of pushing fingers and the frame body.
iii. Structural Inputs:
a. Analysis settings
The motion is constrained on x and Z axis. The set-up is provided with 8 steps interval of displacement. The body is fixed at the end and the edge surface is provided with displacement.
b. Displacement joint
iv. Solutions:
a. Case 1
- Directional Deformation
- Equivalent Stress
- Equivalent Strain
- Contact tool-Pressure
- Force reaction
b. Case 2:
- Directional Deformation
- Equivalent Stress
- Equivalent Strain
- Contact tool-Pressure
- Force reaction
- Fatigue Tool - Life
4. Result:
| (Max values were considered) |
Directional Deformation - (mm) |
Equivalent Stress -(MPa) |
Equivalent Strain- (mm) |
Pressure - (MPa) |
| Case 1 | 5.447 | 601.75 | 0.00855 | 255.04 |
| Case 2 | 7.983 | 356.56 | 0.00518 | 2509.6 |
Fatigue tool life is estimated at about - 110.34 cycles.
5. Conclusion.
The Directional deformation and pressure is significantly higher on the second case, where the pushing finger is near the centre of the geometry. Whereas, the deformation on case 1 is slightly lesser, but the stress values are higher. Since it offers a higher resistance to the given displacement. The study can be accurately analysed with a grid dependency test.
