Using an Encoder with Stepper Motors

value of the step count register as well as the value of the reference position. For example, DP 0, defines the reference position of the X axis to be zero.

Motion Profiler

Reference Position (RP)

Stepper Smoothing Filter

(Adds a Delay)

Output Buffer

Step Count Register (TD)

Output

(To Stepper Driver)

Motion Complete Trippoint

When used in stepper mode, the MC command will hold up execution of the proceeding commands until the controller has generated the same number of steps out of the step count register as specified in the commanded position. The MC trippoint (Motion Complete) is generally more useful than AM trippoint (After Motion) since the step pulses can be delayed from the commanded position due to stepper motor smoothing.

An encoder may be used on a stepper motor to check the actual motor position with the commanded position. If an encoder is used, it must be connected to the main encoder input. Note: The auxiliary encoder is not available while operating with stepper motors. The position of the encoder can be interrogated by using the command, TP. The position value can be defined by using the command, DE.

Note: Closed loop operation with a stepper motor is not possible.

Command Summary - Stepper Motor Operation

COMMAND

DESCRIPTION

Define Encoder Position (When using an encoder) Define Reference Position and Step Count Register Motion Profile Smoothing - Independent Time Constant Stepper Motor Smoothing

Motor Type (2,-2,2.5 or -2.5 for stepper motors) Report Commanded Position

Report number of step pulses generated by controller Tell Position of Encoder

Operand Summary - Stepper Motor Operation

OPERAND

_DEx

_DPx

_ITx

_KSx

_MTx

_RPx

_TDx

_TPx

DESCRIPTION

Contains the value of the step count register for the ‘x’ axis Contains the value of the main encoder for the ‘x’ axis

Contains the value of the Independent Time constant for the ‘x’ axis Contains the value of the Stepper Motor Smoothing Constant for the ‘x’ axis Contains the motor type value for the ‘x’ axis

Contains the commanded position generated by the profiler for the ‘x’ axis Contains the value of the step count register for the ‘x’ axis

Contains the value of the main encoder for the ‘x’ axis

120 • Chapter 6 Programming Motion

DMC-1700/1800

DMC-1800, DMC-1700 specifications

The Galil DMC-1700 and DMC-1800 are advanced motion controllers widely recognized for their high performance and versatility in the automation and robotics industries. These controllers are designed to meet the demands of complex motion control applications, providing users with enhanced features and innovative technologies that optimize motion precision and efficiency.

One of the main features of the Galil DMC-1700 is its ability to handle up to 8 axes of motion control. This capability makes it suitable for a range of applications, from simple point-to-point movements to intricate trajectories in multi-axis systems. In contrast, the DMC-1800 extends this functionality, supporting up to 64 axes, making it ideal for large-scale automation environments.

Both models leverage Galil's powerful programming interface, which simplifies the development of motion control applications. The DMC-1700 and DMC-1800 controllers utilize a high-level programming language that supports advanced motion commands, including linear interpolation, circular interpolation, and complex motion profiles. This feature allows users to implement sophisticated motion sequences seamlessly.

In terms of connectivity, the Galil DMC series offers multiple communication options, including Ethernet, RS-232, and CAN bus, ensuring compatibility with various hardware and enabling easy integration into existing systems. The controllers also come equipped with digital and analog I/O ports, providing flexibility for sensor feedback and actuator control.

The advanced technology incorporated into both the DMC-1700 and DMC-1800 includes on-board PID control, which ensures precise motion control through closed-loop feedback. This results in improved stability and accuracy, particularly in high-speed applications. Additionally, the controllers offer extensive diagnostics and monitoring capabilities, allowing for real-time performance analysis and troubleshooting.

Another notable characteristic of these motion controllers is their compact design, which offers space-saving advantages while maintaining high processing power. Their robust construction and ability to operate in challenging environments make them suitable for a wide range of industrial applications, from CNC machining to assembly lines.

In conclusion, the Galil DMC-1700 and DMC-1800 motion controllers stand out due to their high-performance capabilities, advanced programming features, and flexibility in connectivity. With their ability to handle complex motion control tasks efficiently, these controllers are invaluable tools for engineers and manufacturers looking to enhance their automation processes. By integrating Galil's innovative motion control technology, industries can achieve greater precision, speed, and reliability in their operational workflows.

Galil DMC-1800 Using an Encoder with Stepper Motors, Command Summary Stepper Motor Operation

Models: DMC-1800 DMC-1700

Motion Complete Trippoint