Aerotech BM Series, Руководство по оборудованию

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BM/BMS Series Hardware Manual Appendix A
www.aerotech.com A-5
MMI
Man Machine Interface used as a means of getting operator
data into the system. (See HMI)
Motion Profile
A method of describing a process in terms of velocity, time, and
position.
Motor Brush
The conductive element in a DC brush-type motor used to
transfer current to the internal windings.
Motor, Brushless
Type of direct current motor that utilizes electronic commutation
rather than brushes to transfer current.
Motor, Stepping
Specialized motor that allows discrete positioning without
feedback. Used for noncritical, low power applications, since
positional information is easily lost if acceleration or velocity
limits are exceeded.
NC
Numerical Control. Automated equipment or process used for
contouring or positioning (See CNC). Also, Normally Closed,
referring to the state of a switch.
NEMA
National Electrical Manufacturer’s Association. Sets standards
for motors and other industrial electrical equipment.
Non-Volatile Memory
Memory in a system that maintains information when power is
removed.
Open Collector
A signal output that is performed with a transistor. Open
collector output acts like a switch closure with one end of the
switch at circuit common potential and the other end of the
switch accessible.
Open Loop
Control circuit that has an input signal only, and thus cannot
make any corrections based on external influences.
Operator Interface
Device that allows the operator to communicate with a machine.
A keyboard or thumbwheel is used to enter instructions into a
machine. (See HMI or MMI)
Optical Encoder
A linear or angular position feedback device using light fringes to
develop position information.
Opto-isolated
System or circuit that transmits signal with no direct electrical
connections, using photoelectric coupling between elements.
Orthogonality
The condition of a surface or axis perpendicular (offset 90°) to a
second surface or axis. Orthogonality specification refers to the
error from 90° from which two surfaces of axes are aligned.
Overshoot
In a servo system, referred to the amount of velocity and/or
position overrun from the input command. Overshoot is a result
of many factors including mechanical structure, tuning gains,
servo controller capability, and inertial mismatch.
PID
A group of gain terms in classical control theory (Proportional
Integral Derivative) used in compensation of a closed-loop
system. The terms are optimally adjusted to have the output
response equal the input command. Aerotech controllers utilize
the more sophisticated PID FVFA loop which incorporates
additional terms for greater system performance.
Pitch (of travel)
Angular motion of a carriage around an axis perpendicular to the
motion direction and perpendicular to the yaw axis.
Pitch Error
Positioning error resulting from a pitching motion.
PLC
Programmable Logic Controller. A programmable device that
utilizes “ladder logic” to control a number of input and output
discrete devices.