Micron-Vision

Prerequisites for doing recognition/tracking

The micro-object must have gradient-features. This means:
- The micro-object must be partially in focus. The focused part has to be sufficiently textured.
- The micro-object must have a textured and non-self-similar surface.
- Proper illumination should be chosen, so that the position of the gradient-features is "sufficiently" independent of the angle of the object.
If the object is rotationally symmetric, you shouldn't expect the angle to be meaningful.
The recognition-algorithm is not robust against clutter. This means:
- The background should be as uniform as possible. This can f.e. be achieved by keeping it out of focus.
- The recognition-algorithm is a randomised approach. The required time for reliably recognising a set of micro-objects increases dramatically with number of objects and with background-clutter.
At the moment only one instance per type of micro-object can be recognised.
Besides restrictions mentioned below the algorithm is not scale-invariant.

3-DOF recognition of the intersection of pipette and focal plane using a single image as template

For each micro-object to be recognised with 3-DOF, you need a single image as template. The gradient-features for recognition and tracking are taken from this images:
- Only the desired micro-object should be visible in this image (if this is not possible, there are alternatives like manual post-processing of the image).

4-DOF recognition and tracking of a micro-gripper using a stack of images

For each micro-object to be recognised with 4-DOF, you need a stack of images as template:
- You need a continuous sequence of all images, where the micro-object (and nothing else) is intersecting the focal plane or near to it!
- The distance between the focused planes of two consecutive images must be constant. I.e. you need to take images of equidistant focused planes.
- The pitch- and roll-angle have to coincide with the corresponding angle of the micro-object in the scene (this is not 6-DOF recognition/tracking!).
- There should be no symmetry in the stack.