Preliminary design review 30 january 2007 l.jpg
This presentation is the property of its rightful owner.
Sponsored Links
1 / 35

Preliminary Design Review 30 January 2007 PowerPoint PPT Presentation

  • Updated On :
  • Presentation posted in: General

Preliminary Design Review 30 January 2007. Black Box Car System (BBCS) ctrl + z: Benjamin Baker, Lisa Furnish, Chris Klepac, Benjamin Mauser, Zachary Miers. Motivation. Car accidents Provide proof of who was at fault Provide information about force of crash Other traffic incidents

Download Presentation

Preliminary Design Review 30 January 2007

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

Preliminary design review 30 january 2007 l.jpg

Preliminary Design Review30 January 2007

Black Box Car System (BBCS)

ctrl + z:

Benjamin Baker, Lisa Furnish,

Chris Klepac, Benjamin Mauser,

Zachary Miers

Motivation l.jpg


  • Car accidents

    • Provide proof of who was at fault

    • Provide information about force of crash

  • Other traffic incidents

    • Capture information about what really occurred if ticketed for speeding, following, etc.

Concept of operations goals l.jpg

Concept of Operations:Goals

  • Provide visual information of car’s surroundings for period of time before accident

  • Use accelerometer to determine if accident has occurred

    • If programmed acceleration level occurs, BBCS knows a crash has occurred

    • Force reading will be saved in conjunction with visual data

  • Removable storage

    • Crash video can be viewed on home computer

  • Autonomous

    • In event of accident, data automatically saved

    • Powered by vehicle

Conops requirements l.jpg


Performance Requirements

Block diagram main l.jpg

Block Diagram: Main



Black Box

User interface



Block diagram black box l.jpg

Block Diagram:Black Box




Main Processor













Implementation microcontroller l.jpg


  • Flash-based, 16/32-bit

    • ARM

    • Microchip PIC

    • MSP430

  • Re-programmable

  • On-board ADC, UART, I²C, Timer/counter

  • Interface to sensors, Flash data log

  • USB 1.0/2.0 capable

Implementation microcontroller8 l.jpg


  • One main processor to act as a central processor to control all coprocessors

    • Video processors, memory, accelerometer, etc.

  • Our design will use one processor for each camera module

    • This will allow us to more easily implement several video sources if extended

Implementation video l.jpg


  • We’re looking to use either a CCD or CMOS camera as our video sensor.

  • Ideally we would like to use a camera with USB output and onboard compression.

  • Using a webcam oriented device, we’re hoping to eliminate any need to program USB drivers. With a corresponding USB microcontroller, this might be possible.

Implementation video10 l.jpg


  • Camera – STVS6522

  • Advantages

    • Only needs a 5V supply

    • Large range on input voltage (4.1-5.6)

    • Adjustable Frame Rate

    • Black and White or Color images

    • USB 2.0 compliant

    • Field of depth is infinite with a fixed focus

Implementation video11 l.jpg


  • Disadvantages

    • Operating range isn’t ideal for a full automotive design (32-104 F °)

    • Minimum focus is 20 cm (~8 in)

Implementation video compression l.jpg

Implementation:Video Compression

We assume we are getting raw video from an un-compressed CMOS camera

Estimated needs:

  • Moving JPEG conversion

  • Real time video compression (at least fast enough to convert the first frame by the time the second frame is taken)

Implementation video compression13 l.jpg

Implementation:Video Compression

Implementation video compression14 l.jpg

Implementation:Video Compression

  • Video Conversion Types

    • Digital Camera Coprocessor

    • IC Programmed to do video compression

  • Ideal Setup:

    • CMOS Digital Camera coprocessor for digital still and web cameras

    • Real time video conversion with 50:1 compression ratio

    • I2C or USB data output

Implementation video compression15 l.jpg

Implementation:Video Compression

  • Suppliers:

    • STMicroelectronics

    • Motorola

    • BeyondLogic

    • Digi-Key

Implementation memory l.jpg


  • Fast re-writeable memory to buffer image data.

    • SRAM

      • Advantages

        • Programming simplicity

        • Control simplicity

      • Disadvantages

        • Expensive

        • Limited size

      • Requirements

        • Capable of handling 5 frames/sec video input

        • Low power consumption

Implementation memory17 l.jpg


  • Slow large capacity memory for image data storage

    • Flash

      • Advantages

        • Robust

        • Cheap

      • Disadvantages

        • Slow access speed

      • Requirements

        • Compact Flash interface

Implementation communication l.jpg


  • Ideal Solution

    • I2C

    • USB 2.0 / 1.0

  • Fallback

    • Several I/O ports

Implementation accelerometer l.jpg


  • We’re looking at using a MEMS based accelerometer to detect a crash.

  • The accelerometer is the central trigger for the system.

  • The entire black box is in a looping state until the accelerometer interrupts and sets the system into its crash procedure.

Implementation accelerometer20 l.jpg


  • Accelerometer - LIS3LV02DQ

  • Advantages

    • 3 axes (crash from above?)

    • I2C/SPI output interfaces directly with Microcontroller

    • Factory calibrated with offsets loaded on startup

    • Variable sampling frequency

Implementation accelerometer21 l.jpg


  • Disadvantages

    • 2.5 V operation (increasing complexity with power supply)

    • Configurable to +/- 2 or 6 gs

    • Might trigger too easily

Implementation power l.jpg


We assume we are getting power from a car battery that varies from 8-16V.

  • Estimated needs:

    • One 12V-1A converter for cameras and sensors

    • One 5V-5A and a 3.3V-5A converter for processors, memory, and other circuitry

Implementation power23 l.jpg


Implementation power24 l.jpg


  • Supply Types Available:

    • Linear Voltage Regulators

    • Switching Converters

  • Ideal Setup:

    • 12V-1A, buck-boost

    • 5V-5A, buck

    • 3.3V-5A, buck

Implementation power25 l.jpg


  • Designing the Supply

    • Hard way: Design it by hand, go through plenty of equations, and have a less efficient converter than one you can buy for cheap.

    • Easy way: Go to National Semiconductor, go to the Power Webench, type in your input voltage and your output voltage and current and it designs it for you.

Implementation power26 l.jpg


  • The result for a 12V-1A Supply:

Implementation power27 l.jpg


  • Suppliers:

    • National Semiconductor

    • Texas Instruments

    • STMicroelectronics

    • Analog Devices

    • Many, many others

Implementation user interface l.jpg

Implementation:User Interface

  • Ideal Solution

    • Plug into computer and all video sources show up and start to run

    • On-station displays (LCD or LED on box)

  • Fallback

    • Data display in Windows Application (Excel, Visual Basic, etc.)

    • Data dump to HyperTerminal convert video using program then view video sources

Implementation enclosure l.jpg


  • Ideal Solution

    • Custom Plexiglas enclosure

      • Weatherproof

      • Transparent (for Expo)

      • Strong and Shock resistant (protect equipment in the event of collision)

  • Fallback Solution

    • Generic electronics enclosure

    • Locking metal box

    • Some foam to lessen shock

Contingency plan l.jpg

Contingency Plan

  • No video altogether

    • Instead, base system around inputs of speed, acceleration, braking, blinkers, lights, etc. directly from car

Extensions l.jpg


  • Other sensors

    • Speed

    • Lights, blinkers, brakes

    • GPS

  • Four video sources instead of one

  • 25fps, 30 second video loop

Testing l.jpg


  • Skateboard with system attached to it

    • Push skateboard into wall (collision)

    • Kick skateboard (side collision)

    • Drop basketball on top of car (falling rocks)

    • Hold bacon behind car (Cop with false ticket)

Division of labor l.jpg

Division of Labor

  • Video: Chris Klepac

  • Compression: Zach Miers

  • Power: Ben Baker

  • Accelerometer: Chris Klepac

  • Microcontroller and misc. sensors: Lisa Furnish & Zach Miers

  • Enclosure: Ben Mauser

  • User Interface: Ben Mauser

  • Documentation: All

  • PCB Design: Chris Klepac & Ben Mauser

Schedule l.jpg


Questions l.jpg



  • Login