3D Motion Fit Area Setup (V1)
The camera should be positioned 150cm-190cm from the bike (roughly 5-7 feet) with the lens at a height of 95cm. Relative to the bike the camera should be pointing at the approximate midpoint between bars and saddle.
It is advisable to have the camera level and square to the bike, but it is not necessary to do this with great precision as the calibration process will compensate for any misalignment.
As the system is based on colour recognition it is important to create a good lighting environment. To aid with this we have created a light meter based on information received from the Kinect.
The Kinect automatically adjusts exposure time based on several factors including overall light intensity and white balance of the background.
The lightmeter offers a ‘traffic light’ to show whether the exposure time is acceptable, as well as specifying the actual exposure time. The aim is to be in the green with an exposure time of less than 15ms. Ideal environments achieve exposure times of less than 10ms.
If there is too little light the Kinect will automatically restrict the frame rate to 15fps (and ~60ms exposure time). Even when the light is increased enough to achieve 30fps there can still be motion blur if the exposure time is greater than 20ms (29ms is the minimum to achieve 30fps).
As shown in diagram 1, it is sometimes necessary to have additional lights pointing at the rider and background. We recommend LED lights of 1000-1500lumen (LED is the most efficient and coolest running form of bulb) with a colour temperature of 3000-6500K. In our testing it has not been necessary to turn off other lights (such as overhead) even if they are different types of bulbs (such as CFL or incandescent).
We’ve also found that a white (or light coloured) background makes a big difference to the exposure time. As well as offering a professional look for videos to send to customers. It is possible to have grey logos on the background so your brand appears in videos.
For our test area we’ve installed a remote controlled projector screen (3.3m wide, 2.4m tall) that cost ~USD135.