ADLINK Technology cPCI-8168, User Manual

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Operation Theory 39
4 Operation Theory
This chapter describes the detail operation of the motion controller
card. Contents of the following sections are as follows:
Section 4.1: Classifications of Motion Controller
Section 4.2: Motion Control Modes
Section 4.3: Motor Driver Interface
Section 4.4: Mechanical Switch Interface
Section 4.5: The Counters
Section 4.6: The Comparators
Section 4.7: Other Motion Functions
Section 4.8: Interrupt Control
Section 4.9: Multiple Cards Operation
4.1 Classifications of Motion Controller
In the early years of the servo/stepper driver, motion control drew
more attention than motor control. They separate motor control
into two layers: one is motor control and the other is motion con-
trol. Motor control refers to the PWM, power stage, closed loop,
hall sensors, vector space, and so on. Motion control refers to the
speed profile generating, trajectory following, multi-axes synchro-
nization, and coordinating.
4.1.1 Voltage type motion control Interface
The interfaces of motion and motor control are changing rapidly. In
the early years, people used voltage singals to command the
motor controller. The amplitude of the signal signifies how fast the
motor is rotating and the time duration of the voltage changes sig-
nifies how fast the motor accelerates from one speed to another.
Motor drivers with voltage signal commands are called “analog”
motion controller. It is much eaiser to integrate into an analog cir-
cuit motor controller, but sometimes noise is a big problem for this
type of motion control. In order to control the positioning of a motor
the analog type motion controller must have a position feedback
signal and use a closed loop control algorithm. This increases the
complexity of motion control for a beginner user.