Team Lifted: Critical Design Review Andrew Cober Dan Crowe Sujan Gautam Anthony Schubert Ryan Yeash Overview / Revised Goals Dan Crowe.
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Transcript Team Lifted: Critical Design Review Andrew Cober Dan Crowe Sujan Gautam Anthony Schubert Ryan Yeash Overview / Revised Goals Dan Crowe.
Team Lifted:
Critical Design
Review
Andrew Cober
Dan Crowe
Sujan Gautam
Anthony Schubert
Ryan Yeash
Overview / Revised Goals
Dan Crowe
Overview
Project
Problems and Design Modifications
Hardware/Schematics
Electromagnet Construction
Firmware/Software
Logistics and Administration
Questions
Project: Magnetic Control
Use electromagnets to control the position
of a magnetic object
Control
x and y position
Control object through a user interface
First
approach: buttons
Second approach: touchscreen
Problems Encountered
Power limitations
Prefabricated Electromagnets have
undesired design
Iron core laminates disappointing
Buck converters unable to source
sufficient current
Design Modifications
Control object on 2D surface
Construct electromagnets powerful
enough to meet specifications
Use ferrite cores for lower core loss
Implement H-bridge to divert current
Control position of a magnetic object
Apparatus made of plexiglass
Revised Goals
Effectively control the object with 1cm
accuracy in 2-D plane
Touchscreen sensing
Touchscreen
interface
Object follows a user defined path
Revised Design
Four electromagnets mounted on a
platform
Cyclone II FPGA used to control the
current to the electromagnets through Hbridge
Control based on position of the object
Touchscreen
Hardware/Schematics
Ryan Yeash
Hardware Block Diagram
ADC Conversion Circuit
RS232 Connection
JTAG Connection
Power Circuitry
Electromagnet Control
Electromagnet Specifics
Sujan Gautam
Electromagnets
I-Core solenoid 3.5”x1”x1”
Ferrite core for low power loss and high
magnetic flux density
18 AWG wire to handle sufficient current
and lower resistivity
100-200 turns depending on field output
Some Calculations
Length 3.5”
Number of turns 100
DC current 5 A
Relative permeability
200
B 0.5 Tesla
This does not take into
account the core and wire
loss
Firmware Specifics
Anthony Schubert
Some Altera Details
HAL
Hardware Abstraction
Layer
An API (Application Programming Interface)
for use with Altera’s Nios II modules
Allows easy C programming
Parallel I/O
General
purpose interface for peripherals
Allows for many possible configurations
FPGA Configuration
Current Tasks
Interrupt-driven user interface
Have
been using HAL API to write interrupt handlers
for button inputs
Will eventually use for user input
SRAM
Configured
Cyclone II on development board to use
off-chip SDRAM
Would prefer to use off-chip SRAM
Smaller but faster
Need
off chip memory to use HAL
Start processing ADC input
Controller Firmware
Proportional Controller
Implemented
through control of
electromagnets with PWM
Derivative Controller
Implemented
by calculating the rate at which
the object is moving
Hence PD control
Software Flow Diagram
Initialize
Hardware
Power on
Activate
Magnets
No
Start User
Input
Object
Detected?
Yes
No
User shift?
Center
Object
Yes
No
Shutdown
Sequence
Object
Shifted?
Yes
Logistics and Administration
Andrew Cober
Cost
Qt.
4
1
4
3
2
2
Part
Attained From
Iron Cores
Power Lab
Touchscreen
www.touchscreens.com
H-bridge (complete cost)
Advanced Circuits, Digikey, Mouser
FPGA PCB (complete cost)
Advanced Circuits, Digikey, Mouser
Cyclone II Dev. Board
Tom Brown
18 AWG Magnet Wire
www.bulkwire.com
Misc.
Extra Resistors, Capacitors, etc Digikey
Apparatus (complete cost)
Home Depot
Ferro-Fluid 1L
Ea.
Cost
$0.00
$0.00
$170.00
$170.00
$78.00
$312.00
$116.00
$348.00
$0.00
$0.00
$20.00
$40.00
$30.00
$60.00
$200.00
Total
$1,160.00
Spent
Left
$592.16
$1,320.84
Division of Labor
Andrew
Cober
Mechanical
PCB
Dan Crowe
Anthony
Schubert
Ryan Yeash
Sujan
Gautam
R
CI
R
R
CI
Power
Control
R
R
CI
R
System
Modeling
R
CI
R
R
Control
Algorithm
R
R
R
CI
Firmware
R
R
R
R – Responsible and CI – Consult and Inform
Everyone is informed when a task is completed or needs further
assistance
Timeline Estimate
Milestones
Completed
CDR:
Obtained most parts, started
development of software framework, FPGA
PCB design completed
FPGA PCB Layout Rev. 1
Milestones Continued
Still to come
M1:
Simple one dimensional control and
movement of object
M2: Control x and y coordinates of the object
Expo: Path control and completion of project
Questions
Extra Slides
Risks
Power limitations into the magnets may
limit object size
Control complexity may be too difficult to
implement
May have to rescale from FPGA to MSP
Contingency Plans
Use photo diodes rather than touchscreen
for object position control
Possible Extensions
Addition of LCD to display object data
Touchscreen
for user control
Trackball control
Wireless communication between
apparatus and user interface
Implement multi-core processing on
Cyclone II
NiosII Softcore
FPGA Configuration
Cyclone II FPGA
Nios
II softcore processor
LCD controlled using FSM
Receives commands and data from NIOS II via parallel I/O
May switch to built-in LCD module
Parallel
I/O for button inputs
JTAG module for programming/debug
SRAM/SDRAM controller