Fiducial marker

This method of positioning has since been replaced by GPS, but the term "fiducial" continues to be used as the time reference for data measured during flights.

[2] Fiducials of known pattern and size can serve as real world anchors of location, orientation and scale.

It would also serve to moor the coordinates of the augmented content to the three dimensional location, orientation and scale of the open book, helping to create a stable and accurate fusion of real and synthetic imagery.

A slightly more complex example would be multiple fiducials, each attached to an individual piece in an augmented reality board game.

In applications such as photogrammetry, the fiducial marks of a surveying camera may be set so that they define the principal point, in a process called "collimation".

These systems combine fiducial markers and machine vision to output the location and orientation of colony members multiple times per second and have, among other insights, revealed the social network structure of ant Camponotus fellah.

[14] In radiotherapy and radiosurgical systems, fiducial points are landmarks in the tumour to facilitate correct targets for treatment.

In neuronavigation, a "fiducial spatial coordinate system" is used as a reference, for use in neurosurgery, to describe the position of specific structures within the head or elsewhere in the body.

This center metallic disc can be solder-coated, gold-plated or otherwise treated, although bare copper is most common if not a current-carrying contact.

Consequently, a typical PCB will have multiple fiducials to allow placement robots to precisely determine the board's orientation.

By measuring the location of the fiducials relative to the board plan stored in the machine's memory, the machine can reliably compute the degree to which parts must be moved relative to the plan, called offset, to ensure accurate placement.

Some very low-end boards may use the plated mounting screw holes as fiducials, although this yields very low accuracy.

For prototyping and small batch production runs, the use of a fiducial camera can greatly improve the process of board fabrication.