5a

Imagine that you are in a sailboat sailing due north to a small island ahead of you. Consider the water is exactly flat. There are several islands to the right and left of you and all islands are far away. You have a velocity detector such as a Modified Doppler type that can give your velocity as it has a speed indicator as well as a compass incorporated in the readings it provides.

When you point it at the island due North you find a reading of 10 knots per hour and due north. When you point it to an island exactly due east or west you find 0 speed and the compass direction. Pointing it to an island behind you, you find a negative speed and the direction, if it is straight back the reading is minus 10 knots, due south.

Thus your velocity is variable depending on which way the Doppler is pointed. The speed varies from none to 10 knots back to none back to –10 knots as you rotate the Doppler in a circle. In a real sense the speed varies as to the direction you point the Doppler to. And it is changing to certain landmarks you pass thus it is dependent on your position on the water. So there is a real 2 dimensional plot you can construct of your velocity. One axis could be north south and the other east west if you choose. A graph would be a trigonometric function of your speed, with the maximum positive speed due north and the minimum speed a minus number due south. East and west there would be zero speed so the graph would look like a figure of eight.

In a sense the Velador measures velocity of a real world 3 Dimensional event on to a 2 Dimensional surface. It sees the velocity at right angles to its CCD best and if the motion is straight ahead or straight back it can not measure this motion. In a stationary position it can measure the change of velocity of an event but not the actual velocity. To measure a velocity it needs a reading in one direction to the object and a reading in the opposite direction also. Unfortunately or fortunately the motion in the real world is always changing. This complicates the interpretation of the data the Velador provides. In my study of the many different data sets I find each a challenge to interpret as the information is new and no standards exist. However usually sense can be made of the plots.

3 rules for data interpertation

Listen to the Data. Listen to the data. Listen to the data

Now take the above concepts and apply them to an airplane flying in 3-D space and imagine the different directions the plane can go and measure a particular one direction vecctor. Many different variations of the vector would be obtained by having the plane fly in different directions.

Now imagine the motion vector is rotating and the vector is moving around in 2 dimensions say the x and y plain. Now we are getting close to reality. One more step lets add the 3rd dimension so the motion vector can move in 3 dimensions like a tensor. Now have the airplane measure this flying in various directions

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