Kollmorgen AKD PDMM series, User Manual

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AKD PDMM User Guide | Glossary
Term Description
Frame In networking dialect, a message is called a frame.
Front-end
In software design, the front-end is the part of a software system that interacts
directly with the user.
FW Firmware.
G.p.i.b.
A standardized protocol, analogous to RS-232, for transmitting digital infor-
mation. Unlike RS-232, the GPIB interface (also called IEEE-488) transmits
data in parallel, not serial format (one byte at a time).
Half step
An extended 8-cycle current switching sequence for stepping motors that dou-
bles resolution, reduces noise, and improves resonant conditions.
Hall-effect
sensor
Highly accurate, non-contact limit switch which detects the proximity of a mag-
net and provides a digital output to assure an accurate position reference. Typ-
ical repeatability of the NEAT Hall sensor is ±1-2 microns.
Holding
torque
Stepping motors, when energized, hold position via a magnetic field. The hold-
ing torque is the maximum torque which can be generated before the rotor slips
to the next pole location (7.2 degrees for 200 step/revolution steppers).
Home switch
Any of a variety of sensors which can be used to establish an accurate initial
position. This may consist of a standard end-of-travel Hall sensor; a center
position opto-interrupter with half-travel blocking vane; an index signal on a lin-
ear encoder; a shaft coupling mounted magnet with Hall sensor; or a once-per-
revolution encoder index signal. Once-per-revolution sensors will usually
require a logical or-ing with a linear signal if a unique home position is required.
Homing
The homing procedure allows, based on a position measurement, to set a posi-
tion offset to the motor in order to ensure it is physically at the home position.
Horizontal
Straightness
The horizontal straightness is a horizontal deviation from the straight line of
travel. A horizontal straightness deviation in the travel of the X-axis will cause
a positioning error in the Y direction.
Hysteresis
Error
The hysteresis error is a deviation between the actual and the commanded
position caused by elastic forces accumulated in the motion system. It affects
the accuracy and the bidirectional repeatability.
HW Hardware
Incremental
encoder
(Relative
encoder)
The incremental encoder, sometimes called a relative encoder, is simpler in
design than the absolute encoder. It consists of two tracks and two sensors
whose outputs are called channels A and B. As the shaft rotates, pulse trains
occur on these channels at a frequency proportional to the shaft speed, and the
phase relationship between the signals yields the direction of rotation.
Incremental
move Positioning mode in which moves are referenced from the previously held posi-
tion.
Index Zero pulse (zero signal) of a hardware pin such as digital input or feedback pin.
Index Pulse
A single generated by a second track on the encoder emitter disk that occurs
once per revolution, which can be used to indicate an absolute position of the
motor shaft. Encoder manufacturers identify the index pulse using different
terms such as index, marker, home position and zero reference.
Inductance
The tendency of a motor coil to store energy in a magnetic field. High speed
stepping motor performance is inversely proportional to motor inductance.
Internet
socket
An Internet socket (or commonly, a network socket or socket), is an end-point
of a bidirectional process-to-process communication flow across an IP based
network, such as the Internet. Each socket is mapped to an application proc-
ess or thread. A socket is an interface between an application process or
thread and the TCP/IP protocol stack provided by the operating system. The
plug type is generally RJ-45.
501 Kollmorgen™ | December 2012