DDP - RC p1
Now that you have the ramp set up, you need to calibrate your measurements for baseline data to put in the ProMotion or JavaScript ProMotion and Data Flyer applets later.
First, mark out on your ramp several heights (measured from the table), seperated vertically by 10cm. For example: in the sample ramp, the top is at 85cm, then we placed a mark at 75, 65, 55, 45, & 35cm using masking tape, so the marks are readily visible.
Next, we need to make several trial runs, so we know where the marble will land before we put in a target. Release your marble from the top mark on the ramp, and mark where it lands on the paper you set out in the initial setup. We're aiming for repeatability, so you will need to keep releasing your marble from the same place until you can get (within a couple mm) the marble to land in that spot 3 or 4 times.
If your marble lands in different spots each time, your ramp may be too vertical (causing the marble to lose contact with the foam), or it may be swaying when you drop the marble. If your marble is skipping, adjust the support back to stretch the ramp a bit. If the ramp is swaying, you can tape the sides where it touches the table. Alternatively, you could support the back side of your ramp with some books, bricks, or something else similar, but if you do, make sure that the supports stay constant, because bumping them will have an impact on the later designed-test run.
Repeat the process for the other height marks you made on your ramp (ie 75, 65, 55, etc).
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