Design Process

Final Design

Figure 1: Final virtual reality arena setup. CAD drawing on left and actual arena on right.

Figure 2: A well-known behavior of fruit flies, among researchers in the field, is that flies will turn in the direction of moving strips. The strip patterns above were displayed rotating to the left and right on the spherical display in the virtual reality arena. As can be seen above, not only did the tethered fly respond, but it showed its characteristic behavior by turning in the direction of ration of the strips. This demonstrated that flies would respond to images projected onto the spherical display structure in an open-loop test. Further work is still needed inorder to close the loop.

Figure 3: Left, first test image on test sphere using two projectors. Center and right, tethered fruit fly immersed in static virtual reality image displayed on final sphere.

Figure 4: Example video demonstrating how the image warping software "Pixelwix" works on a test cylinder.

Figure 5: Once image subtraction and ellipse fit was completed angels of the flies wings could be determined as to update the virtual reality simulation.

Figure 6: Final implemented image processing code. Left, picture of tethered fly. Center, background subtraction of wings. Right, ellipse fit to fly’s wings.

Figure 7: Spherical display structure. Left is the test sphere that was used for testing with image warping software. Center is the unmodified final spherical display. Left is the final display sphere with screen goo coating and custom cut holes for imaging and lighting of the tethered fly.

Figure 8: Preliminary design of virtual reality arena. Left is a CAD drawing utilizing one projector and one mirror. Right is a preliminary design based on CAD. Using mirrors presented an number of issues, and due to the uncertainty of the mirror method two projector were used as can be seen in the final design.