-- DanielSantos? - 01 Mar 2007

XYZ Adhesion Testing 4

Test Setup

• 3-axis XYZ stage.
• Control loop at 1kHz embedded on Microchip PIC18F4431?
• Control done using trajectory files with waypoints and linear interpolation
• Sampling force plate at 1kHz.
  • Data filtered at 10 Hz using 3rd order Butterworth filter
• Sampling position data at 500Hz
• Fixed bug with missing encoder ticks
• Increased maximum test length from 65.535 seconds to 2^24 ms
• Substrate and Sample Switch - Sample fixed to force plate, Substrate moving with stage
• Allows for better alignment b/c can see through glass

Experiment #1

Explore the dependance of pulloff force on the pulloff angle.

Procedure

• Preload along 45 degree approach angle to a specified depth in Z (400um, 500um, 600um, 700um)
• Pulloff at specified angle defined by:
  • +Z is the contact normal, +Y is aligned against the "direction of curvature" of the samples, +X to enforce right-handedness
  • Begin with vector, V, aligned along +Z-axis
  • Rotate V about +X-axis by angle Theta, between 0 and 90 (and 95, 100, 105, 110, 115, 120) degrees in 15 degree increments
  • Rotate V about +Z-axis by angle Phi, between 0 and 345 degrees in 15 degree increments
  • Pull-off along vector V
• Pulloff measured by finding maximum value of V-dot-F in sampled force data

Materials

• Sample - Directional Adhesive Pad, #5A
• Substrate - Glass

Results

Experiment #2

Explore the dependance of pulloff force on the approach angle.

Procedure

• Preload along different approach angle (5 to 175 degrees) to a specified depth in Z (400um, 500um, 600um, 700um)
• Pulloff at 30 degrees in YZ plane
• Pulloff measured by finding maximum value of V-dot-F in sampled force data

Materials

• Sample - Directional Adhesive Pad, #5A
• Substrate - Glass

Results

Experiment #3

Explore the dependance of pulloff force on the pulloff angle - detail of YZ plane behavior

Procedure

• Preload along 45 degree approach angle to a specified depth in Z (400um, 500um, 600um, 700um)
• Pulloff at specified angle in YZ plane between -30 and 210 degrees:
  • where 0 degrees is in +Y direction and 180 degrees is in -Y direction
• Pulloff measured by finding maximum value of V-dot-F in sampled force data

Materials

• Sample - Directional Adhesive Pad, #5A
• Substrate - Glass

Results