Ece 477 design review team 1 spring 2008
This presentation is the property of its rightful owner.
Sponsored Links
1 / 28

ECE 477 Design Review Team 1  Spring 2008 PowerPoint PPT Presentation


  • 89 Views
  • Uploaded on
  • Presentation posted in: General

ECE 477 Design Review Team 1  Spring 2008. Alan Bernstein. Ian Alsman. Ilya Veygman. Darshan Shah. Outline. Project overview Project-specific success criteria Block diagram Component selection rationale Packaging design Schematic and theory of operation PCB layout

Download Presentation

ECE 477 Design Review Team 1  Spring 2008

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Ece 477 design review team 1 spring 2008

ECE 477 Design Review Team 1  Spring 2008

Alan Bernstein

Ian Alsman

Ilya Veygman

Darshan Shah


Outline

Outline

  • Project overview

  • Project-specific success criteria

  • Block diagram

  • Component selection rationale

  • Packaging design

  • Schematic and theory of operation

  • PCB layout

  • Software design/development status

  • Project completion timeline

  • Questions / discussion


Project overview

Project Overview

  • Design of a turret with an armature structure that holds an airsoft gun

  • Detect and fire at enemies through both motion and threshold detection

  • Gun will pan/tilt based off coordinates translated by the microcontroller from the video feed

  • Friendlies can disarm the weapon with a remote


Project specific success criteria

Project-Specific Success Criteria

1. An ability to electronically fire an airsoft pistol (either autonomously or manually).

2. An ability to detect off-camera motion via ancillary sensors.

3. An ability to remotely disable device to prevent “friendly fire.”

4. An ability to automatically detect a (hostile) target within the camera’s field of vision.

5. An ability to pan and tilt the firearm assembly (a minimum of) 45° in the longitudinal direction and 30° in the latitudinal direction.


Block diagram

BLOCKDIAGRAM


Component selection rationale

Component Selection Rationale

  • Microcontroller vs. DSP

    • MC9S12XD (144-pin LQFP)

      • 80 MHz

      • 119 GPIO

      • Peripherals: 2 I2C, 6 SCI, 3 SPI

      • External Memory Bus Expansion (XEBI)

      • Easy to Program (JTAG/BDM)

      • Takes only 3.3V supply  much easier

    • DSP56371 (80-pin LQFP) and HC9S12 (32-pin DIP)

      • DSP: 150 MHz, Micro: 8MHz (control code)

      • GPIO: 39 pins

      • No External Memory Bus Expansion

      • DSP instruction set (i.e. filtering)

      • No means of programming

      • Needs 5V, 3.3V and 1.25V supplies  complicated!


Packaging design

Packaging Design

Main Considerations

  • Stability and Mobility

  • Modifiable

  • Housing for PCB, power supply, and other peripherals

  • Motors and Gearing

  • Gun Mount

  • Bearings


Schematic theory of operation

Schematic/Theory of Operation

  • Overview:

    • ON BOARD

      • μC

      • Camera

      • Level translators

      • External RAM

      • Power regulators

      • Motor control logic

      • Fire Control

    • OFF BOARD

      • Motor Driver circuitry (H bridge circuits)

      • Ancillary sensors

        • Motion Detection (motion sensors vs. laser trip wires)

      • Friendly detectors

        • IR or radio remote


Components on board

Components ON BOARD

* 60 pins used for I/O * 25 mA/pin = 1.5 A


Components off board

Components OFF BOARD


Motor control

Motor Control

  • Logic kept on PCB

    • Into PLD:

      • Direction

      • Enable

      • Clock

    • Out:

      • 1st/2nd/3rd/4th coil for some motor turned on

  • Driver circuitry off-board

    • Safety

    • Modularity

    • Current demands


H bridge circuitry off board

H-Bridge Circuitry (OFF BOARD)


Friendly detector and motion sensors

Friendly Detector and Motion Sensors

  • Fire Control

    • Turn AirSoft motor on/off

  • IR Input

    • Multiple off-board sensors summed

    • Range concerns

      • Switch to radio?

  • MS_xxxx

    • Currently motion sensors

    • Care about direction of signal

    • Switch to laser tripwires?


Pcb layout

PCB Layout

  • Main Considerations

    • MC9S12XD documentation suggestions:

      • Decoupling capacitors on supply pairs

      • Star and spoke configuration of copper pour

    • Headers for Microcontroller for easy routing and for future debugging

    • Organization of PCB layout based on voltage (3.3V and 5 V)

    • Separating analog and digital ground

  • Estimated Size: 5 in. X 5 in.


Pcb documentation

PCB Documentation


Component placement

Component Placement

5 V

3.3 V

POWER


Software design development status

Software Design/Development Status

  • Control Code for the Stepper Motors

    • Assembly-based test code

    • Develop Lookup Table

      • Calibration

    • “Learning curve” speed control for smoothness

  • Video Processing/Targeting Code

    • Have basic algorithms

    • Looking for C-based version

  • User Interface Code

    • Should be fairly straightforward


Flow chart visual detect

Flow Chart:VisualDetect

Startup

Capture

backgrounds

Wait

Motion?

No

Yes

Capture

Area and

Subtract

Target

Found?

Coordinates

To Motor

Control

Yes

No


Flow chart control software

Flow Chart:ControlSoftware

Startup

Move to “0,0”

position

Wait

Got

Coords?

No

Wait

Yes

Lookup

corresponding

position

Move main

assembly

Fire


Project completion timeline

Project Completion Timeline

  • 1st week March – Finish tweaking PCB and schematic, make (hopefully) final parts order

  • 7 March – Proof of Parts/Final Schematic/Final Layout

  • Spring Break – Build assembly, begin developing software

  • 3-4th week March – Test software on board as part of development

  • 1st week April – Finish software, begin debugging

  • 15-20 April – Finish debugging/write user manual

  • 23 April – Present PSSCs!!


Timeline

Timeline


Questions discussion

Questions / Discussion


  • Login