Multidisciplinary Engineering Senior Design Project 6508 Controls Lab Interface Improvement Preliminary Design Review 11/11/05 Team Members: Michael Abbott, Neil Burkell Project Sponsor: Dr. Bowman Team Mentors: Dr. Mathew, Dr. Sahin Coordinator: Dr. Phillips Kate Gleason College of Engineering Rochester Institute of Technology

Project Overview Current Controls Lab: –Current System used was purchased from Feedback for use in the Controls Lab which included Analog and Digital Control Boards to be used with a DC Motor. System was designed for technicians not students The Digital Board is outdated Past work from a student has shown the digital board does not work

Project Overview Current Controls Lab: –Digital control is taught through Simulink from varying sampling time and using different methods for converting continuous to discrete transfer functions –There are no hardware experiments using digital controllers A new Digital Board is needed for the Lab

Project Overview Needs for the Controls Lab: –Need to use Simulink on Lab PC –Need to use current Feedback DC Servo Motor and Power Supply The new digital interface must link Simulink to the existing DC motor Exploration into feasible interface concepts is needed (SD I deliverable)

Needs Assessment System must interface Simulink to the motor Capture experimental results accurately User friendly for the students Change sampling time easily for student learning Use existing equipment Be expandable for future labs or projects Have a finished product by the end of Winter quarter Protected from students but also be accessible to be fixed

Requirements Developed The Requirements of the Project are as follows: –The system shall interface MATLAB/Simulink with the Feedback Mechanical Unit ( Servo Motor) already used in the Controls Laboratory. –The user shall input their desired Simulink block diagram in Simulink/MATLAB which will control the Servo Motor using the MATLAB Real-Time Workshop. –The sampling time of the system shall be easily changeable by the user from 1 ms to 300 ms. –The system interface will return real-time data from the Servo Motor to Simulink/MATLAB for analysis and modification of new outputs to control the motor according to Simulink Block Diagram. –The system interface shall have 4 additional digital inputs/outputs, 1 additional analog output, and 7 differential analog inputs beyond the requirement for control of the Servo Motor which may be used in other applications.

Requirements Developed The Requirements of the Project (continued) –The system interface will acquire speed and position of the motor to be used for processing. –Analog inputs shall have a resolution of 16 bits and a range of +10V to -10V. –Analog outputs shall have a resolution of 16 bits and a range of +10V to -10V. –The system interface will be covered to prevent damage/access from lab users. –The system shall use the existing Feedback Power Supply for powering the Servo Motor. –The system shall be able to perform the functions listed in current Controls Lab 8 including effects of sampling time, continuous to discrete conversion, and designing a discrete controller with specifications

MATLABSimulink Real-Time Workshop Real-Time Target Block Diagram of MathWorks Software Organization Digital Controller

Overall System Diagram Lab PC with Matlab and Simulink System Interface Feedback DC Servo Motor Feedback Power Supply Gnd, +-15V, 5V Analog to Motor +-8V to PA(+ve,-ve) Digital from Motor, 6 Grey Code + Index for Position Analog from Motor Tachogenerator +-8V Communication

PA +ve, PA –ve, Tachogenerator +-, Grey code Position indicator Mechanical Unit

Analysis & Synthesis of Design Multiple Concepts were developed 1)Using an Analog Devices DSP Development Kit 2)Using a National Instruments USB Data Acquisition Board  Writing a driver to allow Matlab Real Time Workshop to communicate with board  Using NI Labview Simulation Interface Toolkit Importing Simulink into NI LabVIEW and then running experiments in LabVIEW on PC based DAQ card or external DAQ target 3)Using a National Instruments or Measurement Computing Data Acquisition PCI Card 4)Using xPC Target in Matlab to control a PC with I/O Capability

Analysis & Synthesis of Design Concept 1: Analog Devices DSP Development Kit Analog Devices EZ-KIT

Analysis & Synthesis of Design Concept 1 Feasibility: Analog Devices DSP Development Kit –Need DSPDeveloper software to interface Simulink’s Real Time Workshop with DSP boards –DSPdeveloper requires outdated versions of Matlab, Simulink, and VisualDSP –With software communication works very well with Audio Video DSP Development Kit –System Interface would be portable and could be used in other laboratories –None of the available development kits met our I/O requirements

Analysis & Synthesis of Design Concept 2: National Instruments USB DAQ Board NI USB DAQPAD

Analysis & Synthesis of Design Concept 2 Feasibility: National Instruments USB DAQ Board –Board has necessary I/O Capabilities –System Interface would be portable and could be used with any other PC with Labview –Not supported by Simulink’s Real Time Workshop –Information from MathWorks states that using Simulink with USB is very difficult if not impossible –Labview Simulation Interface Toolkit could be used to convert Simulink Diagram to a Labview DLL but would require student’s knowledge of Labview programming to interface the device

Analysis & Synthesis of Design Concept 3: National Instruments/Measurement Computing PCI DAQ Card

Analysis & Synthesis of Design Concept 3 Feasibility: National Instruments/Measurement Computing PCI DAQ Card –PCI Card meets all requirements for I/O’s –PCI Card is supported by Simulink and Real Time Workshop –No additional software would need to be purchased –Additional breakout hardware would be necessary –System Interface would not be portable –Only NI cards supported by MathWorks are E-Series (top of the line $$) –Measurement Computing PCI Card is cheaper

Analysis & Synthesis of Design Concept 4: Using xPC Target in Matlab to control a PC with I/O Capability

Analysis & Synthesis of Design Concept 4: Using xPC Target in Matlab to control a PC with I/O Capability –5 Different PC configurations supported by MathWorks were explored: xPC Targetbox from MathWorks with needed I/O’s General Standards PC/104 Board with needed I/O’s Real Time Devices PC/104 Board with needed I/O’s Dell PC with PCI DAQ Card from National Instruments or Measurement Computing Shuttle Barebones PC with PCI DAQ Card from National Instruments or Measurement Computing

Analysis & Synthesis of Design Concept 4 Feasibility: Using xPC Target in Matlab to control a PC with I/O Capability –Need to add xPC Target Toolbox to MathWorks license –Each configuration is already supported by MathWorks –Each configuration would have the necessary I/O Configuration –System interface would be portable –Expandable for other projects and labs –Each configuration is very different in price per seat

BOM & Costs Concepts 1-3 Bill of Materials and Lead Times

BOM & Costs Concept 4 Bill of Materials and Lead Times

BOM & Costs Concept 4 Bill of Materials and Lead Times (Continued)

BOM & Costs Bill of Materials common to all concepts: –Prototype Board $4.29 –34-Way Ribbon Cable Male Connector $3.64 (50 day lead time)

Gantt Chart of Fall Quarter

SD II Project Plan

Our Recommendation for Implementation Concept 4 with a PC104 board from Real Time Devices or the Shuttle PC with a PCI DAQ Card from either NI or Measurement Computing covers all of the needs and is most feasible for implementation by the end of winter quarter –Lowest cost per seat –Portable interface –Supported by MathWorks –Expandable

Anticipated Design Challenges/Risk Risks: –Lead time on parts –Availability of connectors Design Challenges: –Hardware compatibility issues –Wiring I/O from interface to motor –Organizing received data from interface

Questions? Suggestions?