Page 127 - Concise Encyclopedia of Robotics

Fluxgate Magnetometer
The FTS is a remote-controlled robot. The extent to which it is con-
trolled depends on the design. The simplest FTS machines are program-
mable from the spacecraft’s main computer. More complex FTS devices
make use of telepresence.
Because of the risk involved in sending humans into space, scientists
have considered the idea of launching FTS-piloted space shuttles to deploy
or repair satellites.The FTSs would be controlled through computers on the
ground and in the spacecraft. One FTS design has the appearance of a
one-legged, headless android, as shown in the illustration.
See also TELEPRESENCE.
FLOWCHART
A flowchart is a diagram that illustrates a logical process or a computer
program. It is a block diagram. Boxes indicate conditions, diamonds
indicate decision points, and arrows show procedural steps.
Flowcharts are used to develop computer software. They are also used
in troubleshooting of complex equipment. Flowcharts lend themselves
well to robotic applications, because they indicate choices that a robot
must make while it accomplishes a task.
A flowchart must always represent a complete process. There should
be no places where a technician, computer, or robot will be left without
some decision being made. There must be no infinite loops, where the
process goes in endless circles without accomplishing anything.
Examples of flowcharts are shown in the definitions of BRANCHING and
FEEDBACK.
FLUXGATE MAGNETOMETER
A fluxgate magnetometer is a computerized robot guidance system that
uses magnetic fields to derive position and orientation data. The device
uses coils to sense changes in the geomagnetic field (Earth’s magnetic
field), or in an artificially generated reference field.
Navigation within a defined area can be carried out by having the robot
controller constantly analyze the orientation and intensity of the magnetic
flux field generated by strategically placed electromagnets. A computer
map of the flux field, showing two electromagnets and a hypothetical robot
in the field, is shown in the illustration. In this case, opposite magnetic
poles (north and south) face each other, giving the flux field a characteristic
bar-magnet shape.
For each point in the work environment, the magnetic flux has a
unique orientation and intensity. Therefore, there is a one-to-one cor-
respondence between magnetic flux conditions and each point inside
the environment. The robot controller is programmed to “know” this

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