Sample Plate Shadow Test Results

Task Description: Using a light source in front of the 3D printed Payload in a dark room, measure shading angles for each sample row. This test defines the required angles for the ADCS.

Completed: 20 Aug. 2020

Conducted and documented by: Ali

Resources Required: EM payload module, Protractor Circle Diagram, free rotating circular plate, LED focusing flashlight

Verification Activities: V-PLD-0020

Pass Criteria:

• Verify that the maximum sun vector angle in X, Y, and Z axes before samples are shaded is at least 24 degrees from the sun-vector.

In this test, we measured shading angles in Z and Y-axis for each sample row. However, in order to simulate sunlight for the payload module, we considered some assumptions.

● We used a flashlight in its focused mode to provide more directional light like the sun.

● We put the flashlight in 480 cm from the payload module.

Important Note:

Because of the lack of enough space in the room, we couldn’t put the flashlight further from the payload module to evaluate the effect of distance on the shading angles. The shading angles would be decreased as the flashlight distance to the payload module increases. But, at a certain point, the changes in shading angles will be negligible.

The differences between the calculated and measured shadow angles are shown in the table below. These show that the measured shadow angles tend to be slightly larger than those calculated (except for row 6 where the protuberance caused the sample to become shaded sooner). Some of this difference between measured and calculated angles might be caused by the closeness of the light source but the sun is not a perfect point-source either, and so we believe these results are reasonable.