Galil DMC-13X8 System Design and Compensation

USER MANUAL Chapter 10 Theory of Operation • 167

1

4

0.1

50 200 2000 W (rad/s)

Magnitude

Figure 10.8 - Bode plot of the open loop transfer function

For the given example, the crossover frequency was computed numerically resulting in 200 rad/s.

Next, we determine the phase of A(s) at the crossover frequency.

A(j200) = 390,000 (j200+51)/[(j200)2 . (j200 + 2000)]

α = Arg[A(j200)] = tan-1(200/51)-180° -tan-1(200/2000)

α = 76° - 180° - 6° = -110°

Finally, the phase margin, PM, equals

PM = 180° + α = 70°

As long as PM is positive, the system is stable. However, for a well damped system, PM should be

between 30 degrees and 45 degrees. The phase margin of 70 degrees given above indicated

overdamped response.

Next, we discuss the design of control systems.

System Design and Compensation

The closed-loop control system can be stabilized by a digital filter, which is preprogrammed in the

DMC-13X8 controller. The filter parameters can be selected by the user for the best compensation.

The following discussion presents an analytical design method.

The Analytical Method

The analytical design method is aimed at closing the loop at a crossover frequency, ωc, with a phase

margin PM. The system parameters are assumed known. The design procedure is best illustrated by a

design example.

Contents

Main DMC-13X8 Using This Manual Contents Page Page Page Page Page Chapter 1 Overview Introduction Overview of Motor Types Standard Servo Motor with +/- 10 Volt Command Signal Brushless Servo Motor with Sinusoidal Commutation DMC-13X8 Functional Elements Microcomputer Section Motor Interface Communication General I/O System Elements Motor Amplifier (Driver) Encoder Watch Dog Timer Page Chapter 2 Getting Started The DMC-13X8 Motion Controller Elements You Need Installing the DMC-13X8 Step 1. Determine Overall Motor Configuration Standard Servo Motor Operation: Sinusoidal Commutation: Stepper Motor Operation: Step 2. Install Jumpers on the DMC-13X8 Address Jumpers Master Reset and Upgrade Jumpers Opto Isolation Jumpers Hardware IRQ (Interrupt) Jumpers Step 3. Install the DMC-13X8 in the VME Host Step 4. Establish Communication with the Galil controller Step 5. Determine the Axes to be Used for Sinusoidal Commutation Notes on Configuring Sinusoidal Commutation: Example: Sinusoidal Commutation Configuration using a DMC-1348 Step 6. Make Connections to Amplifier and Encoder. Page Step 7a. Connect Standard Servo Motors Check the Polarity of the Feedback Loop Inverting the Loop Polarity Chapter 2 Getting Started 24 USER MANUAL J7 J6 J51 DC Servo Motor + - Y W Z USER MANUAL Chapter 2 Getting Started 25 J7 J6 - J51 DC Power Supply + + - Step 7b. Connect Sinusoidal Commutation Motors Example: Sinusoidal Commutation Configuration using a DMC-1348 If Hall Sensors are Available: If Hall Sensors are Not Available: If Hall Sensors are Available: Step 8. Tune the Servo System Design Examples Example 1 - System Set-up Example 2 - Profiled Move Example 3 - Multiple Axes Objective: Move the four axes independently. Example 4 - Independent Moves The motion parameters may be specified independently as illustrated below. Example 6 - Absolute Position Example 7 - Velocity Control Example 8 - Operation Under Torque Limit Example 9 - Interrogation Example 10 - Operation in the Buffer Mode Example 11 - Using the On-Board Editor To exit the editor mode, input <cntrl>Q. The program may be executed with the command. Example 12 - Motion Programs with Loops Motion programs may include conditional jumps as shown below. After the above program is entered, quit the Editor Mode, <cntrl>Q. To start the motion, command: Example 13 - Motion Programs with Trippoints The motion programs may include trippoints as shown below. Example 14 - Control Variables Example 15 - Linear Interpolation Example 16 - Circular Interpolation Page Chapter 3 Connecting Hardware Overview Using Optoisolated Inputs Limit Switch Input Home Switch Input Abort Input Uncommitted Digital Inputs Wiring the Optoisolated Inputs Using an Isolated Power Supply Bypassing the Opto-Isolation: Analog Inputs Amplifier Interface TTL Inputs TTL Outputs Page Chapter 4 Communication Introduction Communication with Controller Communication Registers Simplified Communication Procedure Read Procedure Write Procedure Advanced Communication Techniques Changing Almost Full Flags Communication with Controller - Secondary FIFO channel Polling FIFO Polling Mode Read Procedure Overview of Secondary FIFO Procedure: DMA / Secondary FIFO Memory Map Page Explanation of Status Information and Axis Switch Information General Status Information (1 Byte) Axis Switch Information (1 Byte) Axis Status Information (2 Byte) Coordinated Motion Status Information for S or T plane (2 Byte) Interrupts Setting up Interrupts Configuring Interrupts Page Servicing Interrupts Example - Interrupts Controller Response to DATA Chapter 5 Command Basics Introduction Command Syntax - ASCII Coordinated Motion with more than 1 axis Command Syntax Binary Binary Command Format Header Format: Datafields Format Example Binary command table Controller Response to DATA Interrogating the Controller Interrogation Commands Summary of Interrogation Commands Interrogating Current Commanded Values. Operands Page Page Chapter 6 Programming Motion Independent Axis Positioning Command Summary - Independent Axis Operand Summary - Independent Axis Example - Absolute Position Movement Example - Multiple Move Sequence Page Independent Jogging Command Summary - Jogging Operand Summary - Independent Axis Example - Jog in X only Example - Joystick Jogging Linear Interpolation Mode Specifying Linear Segments Additional Commands An Example of Linear Interpolation Motion: Specifying Vector Speed for Each Segment Changing Feedrate: Command Summary - Linear Interpolation Operand Summary - Linear Interpolation Example - Linear Move V S VZ VW=+ Example - Multiple Moves Vector Mode: Linear and Circular Interpolation Motion Specifying the Coordinate Plane Specifying Vector Segments Additional commands Specifying Vector Speed for Each Segment: Changing Feedrate: Compensating for Differences in Encoder Resolution: Trippoints: Tangent Motion: Example: Command Summary - Coordinated Motion Sequence Operand Summary - Coordinated Motion Sequence Electronic Gearing Command Summary - Electronic Gearing Example - Simple Master Slave Example - Electronic Gearing Example - Gantry Mode Example - Synchronize two conveyor belts with trapezoidal velocity correction. Electronic Cam Page Page Page Command Summary - Electronic CAM Operand Summary - Electronic CAM Example - Electronic CAM The following example illustrates a cam program with a master axis, Z, and two slaves, X and Y. Contour Mode Specifying Contour Segments Page Additional Commands () Command Summary - Contour Mode = Operand Summary - Contour Mode General Velocity Profiles Contour Mode Example Teach (Record and Play-Back) Record and Playback Example: Virtual Axis Stepper Motor Operation Specifying Stepper Motor Operation Stepper Motor Smoothing Monitoring Generated Pulses vs Commanded Pulses Motion Complete Trippoint Using an Encoder with Stepper Motors Command Summary - Stepper Motor Operation Operand Summary - Stepper Motor Operation Stepper Position Maintenance Mode (SPM) YC YBYATP TDQS = Error Limit Correction Example: SPM Mode Setup Example: Error Correction Page Example: Friction Correction Dual Loop (Auxiliary Encoder) Using the CE Command Additional Commands for the Auxiliary Encoder Backlash Compensation Continuous Dual Loop - Example Sampled Dual Loop - Example Motion Smoothing Using the IT and VT Commands: Example - Smoothing Using the KS Command (Step Motor Smoothing): Homing USER MANUAL Chapter 6 Programming Motion 103 EN End Figure 6.8 - Motion intervals in the Home sequence Command Summary - Homing Operation Operand Summary - Homing Operation High Speed Position Capture (The Latch Function) Fast Update Rate Mode Page Chapter 7 Application Programming Overview Using the DMC-13X8 Editor to Enter Programs Edit Mode Commands Program Format Using Labels in Programs Special Labels Commenting Programs Using the command, NO Executing Programs - Multitasking Debugging Programs Trace Commands Error Code Command Stop Code Command RAM Memory Interrogation Commands Operands Debugging Example: Program Flow Commands Event Triggers & Trippoints DMC-13X8 and DMC-13X8 Event Triggers Event Trigger Examples: Event Trigger - Multiple Move Sequence Event Trigger - Set Output after Distance Event Trigger - Repetitive Position Trigger Event Trigger - Start Motion on Input Event Trigger - Set output when At speed Event Trigger - Change Speed along Vector Path Event Trigger - Multiple Move with Wait Define Output Waveform Using AT Conditional Jumps Command Format - JP and JS Logical operators: Conditional Statements Multiple Conditional Statements Using the JP Command: Using If, Else, and Endif Commands Using the IF and ENDIF Commands Using the ELSE Command Nesting IF Conditional Statements Command Format - IF, ELSE and ENDIF Example using IF, ELSE and ENDIF: Subroutines Example: Stack Manipulation Auto-Start Routine Automatic Subroutines for Monitoring Conditions Example - Limit Switch: Example - Position Error Example - Input Interrupt Example - Motion Complete Timeout Example - Command Error Example - Command Error w/Multitasking Mathematical and Functional Expressions Mathematical Operators Bit-Wise Operators Functions Variables Programmable Variables Assigning Values to Variables: Assigning Variable Values to Controller Parameters Displaying the value of variables at the terminal Example - Using Variables for Joystick Operands Examples of Internal Variables: Special Operands (Keywords) Examples of Keywords: Arrays Defining Arrays Assignment of Array Entries Using a Variable to Address Array Elements Uploading and Downloading Arrays to On Board Memory Automatic Data Capture into Arrays Command Summary - Automatic Data Capture Data Types for Recording: Note: X may be replaced by Y,Z or W for capturing data on other axes. Operand Summary - Automatic Data Capture Example - Recording into An Array Input of Data (Numeric and String) Input of Data An Example for Inputting Numeric Data Cut-to-Length Example Inputting String Variables Output of Data (Numeric and String) Sending Messages Formatting Messages Using the MG Command to Configure Terminals Summary of Message Functions: Displaying Variables and Arrays Interrogation Commands Using the PF Command to Format Response from Interrogation Commands Removing Leading Zeros from Response to Interrogation Commands Local Formatting of Response of Interrogation Commands Formatting Variables and Array Elements Local Formatting of Variables Converting to User Units Hardware I/O Digital Outputs Digital Inputs Example - Start Motion on Switch Input Interrupt Function Examples - Input Interrupt Analog Inputs Example - Position Follower (Point-to-Point) Example - Position Follower (Continuous Move) Example Applications Wire Cutter X-Y Table Controller Y X Speed Control by Joystick Position Control by Joystick Backlash Compensation by Sampled Dual-Loop Page Page Chapter 8 Hardware & Software Protection Introduction Hardware Protection Output Protection Lines Input Protection Lines Software Protection Programmable Position Limits Off-On-Error Automatic Error Routine Limit Switch Routine Page Chapter 9 Troubleshooting Overview Installation Communication Stability Operation Page Chapter 10 Theory of Operation COMPUTER CONTROLLER DRIVER LEVEL Operation of Closed-Loop Systems System Modeling [] ( R L T Current Drive Velocity Loop VEWP VOLTAGE SOURCE VWP VIWP CURRENT SOURCE VELOCITY LOOP DAC Digital Filter ZOH System Analysis Page System Design and Compensation The Analytical Method Page Page Equivalent Filter Form Appendices Electrical Specifications Servo Control Stepper Control Input/Output Performance Specifications Connectors for DMC-13X8 Main Board Notes: X,Y,Z,W are interchangeable designations for A,B,C,D axes. Pin-Out Description for DMC-13X8 Accessories and Options ICM-1900 Interconnect Module Page Page Page ICM-1900 Drawing AMP-19X0 Mating Power Amplifiers ICM-2900 Interconnect Module Page Page Opto-Isolated Outputs ICM-1900 / ICM-2900 (-Opto option) Standard Opto-isolation and High Current Opto-isolation: 64 Extended I/O of the DMC-13X8 Controller Configuring the I/O of the DMC-13X8 Saving the State of the Outputs in Non-Volatile Memory Accessing extended I/O Connector Description: Page J8 50-PIN IDC IOM-1964 Opto-Isolation Module for Extended I/O Controllers Description: 0 1 32 5 764 Overview Configuring Hardware Banks Digital Inputs Page High Power Digital Outputs Standard Digital Outputs Electrical Specifications Digital Inputs High Power Digital Outputs Standard Digital Outputs Maximum sink current: 2mA Relevant DMC Commands Screw Terminal Listing Page * Silkscreen on Rev A board is incorrect for these terminals. Coordinated Motion - Mathematical Analysis Y CD B A X VS Tsta=+=0 407. DMC-13X8/DMC-1300 Comparison List of Other Publications Training Seminars Contacting Us WARRANTY Page Index