Preliminary Design Review
Multispectral Camera
Advisor: Prof. Mario Parente
Team Parente
#13
Simon Belkin
Audrey C. Finken
Matthew Walczak
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Team Parente
Simon Belkin
- EE
- Team
Manager
Matthew Walczak
- EE
- Website Master
Audrey Finken
- EE
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Outline
 The Problem
 Background
 Our solution
 Application
 Requirements
 Design alternative
 Timeline/MDR Goals
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The Problem
 Normal camera just take pictures with
RGB color filter that show light at three
different wavelengths.
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The Problem:
 We want to expand the capabilities of
normal cameras by covering a wider
spectrum of colors through the use of
a Multispectral dddddddd33333333333
Camera.
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Background
The Camera will be operated by a
microcontroller system that will position a filter
in front of a monochrome camera and an
image will be captured
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Multispectral camera: background
Images taken through different optical filter contain
only certain wavelengths of the electromagnetic
spectrum that the filter allows through.
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Solution: Multispectral Camera
 Create picture at different wavelengths
that regular vision does not allow(Near
Infrared).
 Have various applications not
accessible by regular cameras.
 The provide more information to user.
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Block Diagram
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Applications
Food processing
Agriculture
Defects such
as bruising
on fruit are
more easily
isolated in By studying changes in
an infrared reflectivity, growers can identify
image.
plant stress resulting from
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problems such as water
shortage, nutrient deficiencies,
or toxins long before there is
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any visible indication.
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Requirement Analysis : specifications
 Electronically control the filter wheel and
monochrome camera attached to it.
 Battery powered
 Enclosing case big enough to hold
monochromatic camera.
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Filter Wheel
 This consist of six or more optical band pass
filters.
 Filter are mounted in a computer controlled filter
wheel located between lens and gray level
sensor.
 Calibration of color wheel
turning to be able to have a
particular step size.
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Filter Wheel Challenge: Electronic part
 Connection of the filter
− Use logic analyzer
− Use schematic of filter to
figure out pins
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Monochromatic camera
 Choosing the Monochromatic camera
 Photographs images through the filter
wheel in particular frequency spectrum.
 Camera settings
− Frame rate, latency, exposure, aperture
and gain
 Enclosed area to prevent light between
the Wheel and camera.
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Monochromatic camera challenge :optics
 Aberration:
− Geometric: Each filter is tilted with respect to axis
can cause distortion.
− Chromatic : When different wavelengths of light
aren't focused on same plane.
− Ghosting: Images produce reflections between the
image sensor and filter surface.
 Can be solved via software
− Minimize aberration with proper choice of lens and
optics
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Microcontroller circuit
 Controls the filter wheel’s turning.
 Will collect different image spectrums
 Include a display mode
− Raspberry pi (tentative)
 Microcontroller development board
− Arduino board or chip
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Mechanical assembly
 Having all the parts fit together
− Filter
− Optics (lens, camera)
− Microcontroller
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Design alternative: CCD
 Using a CCD behind the filter wheel:
 Advantages:
− More sensitive to a broad range of
wavelengths
 Disadvantages:
− Alignment
− Have to deal with optical distortion.
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MDR Deliverables
ID Task Name
Start
Finish
Duration
1 PDR
10/5/2012
10/15/2012 10 days
2 MDR
10/15/2012
12/6/2012 52 days
3 Mid report
11/8/2012
12/10/2012 32 days
4 CDR
12/6/2012
2/28/2013 84 days
5 FPR
2/28/2013
4/12/2013 43 days
6 SDP Day
2/10/2013
4/19/2013 68 days
7 Final Report
1/22/2013
5/1/2013 99 days
8 Research Filter Wheel
10/8/2012
10/31/2012 23 days
9 Access Filter Wheel with Microcontroller
11/1/2012
12/5/2012 34 days
10/12/2012
11/1/2012 20 days
11 Obtain Rotating Filter Wheels
11/1/2012
11/25/2012 24 days
12 Research Filter Camera Lens
10/8/2012
11/1/2012 24 days
13 Obtain Camera Lens
11/1/2012
11/20/2012 19 days
14 Research Monocromatic Camera/CCD
10/5/2012
11/1/2012 27 days
15 Obtain Monocromatic Camera/CDD
11/1/2012
11/20/2012 19 days
16 Access Monocromatic Camera with Microcontroller
11/20/2012
12/6/2012 15 days
17 Research Microcontroler
10/10/2012
11/15/2012 36 days
18 Software adjusting for aberations of One Color
11/15/2012
1/22/2013 68 days
19 Software adjusting for aberations of Two Colors
12/6/2012
2/28/2013 84 days
20 Software adjusting for aberations of All Colors available in Filter Wheel
12/6/2013
4/12/2013 127 days
10 Research Extra Rotating Filter Wheels
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Oct-12
Nov-12
Dec-12
Jan-13
Feb-13
Mar-13
Apr-13
May-13
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Thank you for your Time! – Questions?
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