introduction - personal.stevens.edupersonal.stevens.edu/.../hw8/quirk_camera_level_indic… ·...

CPE 322 Camera Level Indicator – FINAL REPORTThomas Dabay, Kris Engel, David Quirk

5/4/2011I pledge my honor that I have abided by the Stevens Honor System

Table of ContentsIntroduction.........................................................3

Technical Information................................................5

Functional Description..............................................5

Microcontrollers..................................................5

Gyroscopes........................................................5

Hot Shoe Technology...............................................7

Battery...........................................................7

LEDs..............................................................8

Putting it all Together...........................................8

Technical Description...............................................9

Microcontroller...................................................9

Gyroscope........................................................12

Hot Shoe.........................................................12

Putting it all Together..........................................14

Performance Expectations...........................................16

The Arduino......................................................16

Gyroscope........................................................18

Critical Evaluation.................................................22

The “Good”.........................................................22

The “Scary”........................................................22

The “Fun”..........................................................22

Funding............................................................22

Summary.............................................................24

Vita................................................................25

Thomas Dabay.....................................................25

Kris Engel.......................................................25

David Quirk......................................................25

Bibliography........................................................26

Thomas Dabay, Kristopher Engel, David Quirk | Camera Level Indicator FINAL REPORT

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IntroductionThe general idea of this project is to create an embedded camera level indicator primarily for SLR cameras. A common issue in taking handheld pictures is keeping the camera body level without the use of a tripod. There are several bubble-based leveling devices out on the market – not unlike the devices used in woodworking. The one drawback to these products however, is the fact that you must look at the bubble level, which rests on top of the camera. This causes the user of the camera to constantly switch from looking at the top of the camera to looking through the viewport. Obviously, the movement of the camera from looking at the top of it and then back through the viewfinder will cause the user to tilt the camera in some way. Pictures would come out crooked a couple of degrees one way or another.

The group aims to rectify this by introducing a product that will build a level indicator right into the viewfinder and eliminate this problem. This product will encompass a processing unit paired with a gyroscopic sensor. Attached is a replica eyepiece that replaces the stock eyepiece and has LEDs embedded to indicate the level of the camera. This will allow the user to see if their camera is level without having to take their eyes off of the action and get a level picture every time.

The general construction will try to encompass all of these parts into a single, plastic unit. The unit will be an L shape, with the largest part sliding onto the top of the camera into the Hot Shoe port. Hanging down from this will be a replacement viewfinder embedded with fiber optics. This proposed Hot Shoe port is located on all SLR cameras. The top of the unit will include another Hot Shoe port to serve as a pass-through in case the user has an external flash accessory. Many cameras come with a stock flash that pops up on the camera when needed. The group hopes to make this device as small as possible in order to fit on top of the camera body without issue and to allow for a photographer to continue using the embedded flash unit on the camera body if inclined to. The group also hopes to keep it small in order to not throw off the balance of the camera and make it too cumbersome. Because external flash devices can be heavy, the group must take this into consideration to make the device sturdy. The group intends to make this product as universal as possible, but for purposes of the initial design, the group used the Canon Rebel XT as shown in Figure 1.


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This paper will outline all technical aspects of the project. This will include the functional description of the design and all of the components involved in its operation. It will also outline the technical descriptions of the same components. The principals involved in the project (software and lower-level design aspects) will be outlined as well as the performance expectations and objectives for the device itself and the project as a whole. The group will reflect upon the good, scary and fun aspects of the project and try to bring the project down to a level of reasonableness and reality by observing these points as well as how to fund the project.

Figure 1 - Canon Rebel XT. Used as a reference for project.


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Technical InformationThis section will include the functional description, technical description and metrics in which the group established in order to choose each component to comprise the camera level indicator.

Functional DescriptionThere are five main components involved with the group’s project. Here the group will introduce and discuss each component and their functions on a basic, non-technical level.

MicrocontrollersA normal computer consists of a central processing unit (CPU), memory (random access memory, RAM, and hard disk space) and input and output functions (I/O). The CPU takes care of the logic and mathematic functions. Think of this as the brain of the machine. The memory is where data is stored. The I/O dictates how the computer moves data between components. This is analogous to the nervous system. I/O is responsible for devices such as mice, keyboards, printers and monitors. A microcontroller takes all three main components and packs them into one small board. Microcontrollers are relegated to simpler, singular tasks and are used in specialized products. They lack the raw power that a desktop computer has. A regular desktop computer can perform thousands of tasks, but a microcontroller excels only at one. In the case of this project, the group aims to limit the microcontroller to communicating with 4 devices in a relatively simple manner. In doing so, the microcontroller will be more than capable of providing the power needed to perform the calculations.1

GyroscopesA gyroscope is any device that is able to measure angular velocity. The first gyroscopes were created in the 1800s, although similar devices were used for ship navigation as early as the 1700s. In 1852, Leon Foucault coined the term “gyroscope”. The 1900s saw many improvements to the gyroscope, namely with the introduction of optical gyroscopes using lasers, which found success in aeronautics and military applications, and Microelectromechanical Systems (MEMS) gyroscopes, which thanks to their small size and ability to be mass produced are popular in many applications. The commercial applications of gyroscopes, especially MEMS gyroscopes, are wide and varied and span major categories such as automotives, consumer electronics, aerospace, military, and industrial applications.

1 Westfw http://www.instructables.com/id/How-to-choose-a-MicroController/


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http://www.instructables.com/id/How-to-choose-a-MicroController/

As mentioned above, the MEMS gyroscope has the advantage of small physical size and good manufacturability, which leads to lower prices for consumers. It is because of these properties that they are of special interest to this project. They are also very accurate compared to older mechanical gyroscopes. There are various different types of MEMS gyroscope, but most make use of vibrating mechanical elements to sense rotation. As such, they lack rotating parts and bearings, which is what allows them to be miniaturized effectively. All such vibratory MEMS gyroscopes make use of Coriolis acceleration in sensing rotation. Most MEMS gyroscopes can be broken down into three quality levels. In increasing quality levels, they are rate, tactical, and inertial grade.

The first type of MEMS gyroscope is known as the tuning fork design, which originated in Charles Stark Draper Lab. The tuning fork design consists of two tines connected to a junction bar which resonate at a certain amplitude. When those tines rotate, the Coriolis Effect causes force applied perpendicular to the tines. This force can be detected and is proportional to the angular rate. The force is detected by changes in the capacitance of gyroscope because the distance between the tines is affected by the force.

Another type of MEMS gyroscope is the vibrating wheel gyroscope. It consists of a wheel that is driven to vibrate about its axis of symmetry. When rotation occurs about either in-plane axis, the wheel tilts, which can be sensed with capacitive electrodes placed under the wheel. One advantage of vibrating wheel gyroscopes is their ability to sense two axes of rotation with a single vibrating wheel.

The next type of MEMS gyroscope is the Piezoelectric Plate Gyroscope. It is preferable to other types of MEMS gyroscope because of the lower drive voltage required for readable outputs. It consists of a piezoelectric plate suspended over a silicon wafer. Leads are connected to each of the 6 sides of the piezoelectric plate, and the leads provide the driving voltage and measure the output as the plate vibrates.

A final type of MEMS gyroscope is the wine glass resonator type. In this type, the resonant ring is driven to resonance and the positions of the nodal points indicate the rotation angle. Although the input and output modes are nominally degenerate, but due to imperfect machining some tuning is required.


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One common drawback of a MEMS gyroscope is that most output an angular rate measurement, instead of an absolute angle measurement. Ideally, this would not be a problem, because one would only need to integrate the angular rate measurements to get an absolute measurement. However, because of various errors in measurement (bias error, random error/noise, etc.); this method can become very inaccurate. As such, either proprietary measures are necessary or one must calibrate each individual sensor. For full manufacturing, proprietary measures are usually more economically viable, but for prototyping, testing, and small batch manufacturing, calibration is often preferable. With proper calibration, most MEMS gyroscopes are able to reach less than 1% error rates when measuring absolute angles.2

Hot Shoe TechnologyThe Hot Shoe is a port located on top of most, if not all, SLR cameras (digital and film) and a handful of upscale point-and-shoot cameras. Figure 1 on page 4 shows a top view shot of the Canon Rebel XT which includes the Hot Shoe port. This port is used to provide a mounting point for an external flash or flash system. The port has a multitude of contacts that connect from the Hot Shoe and provide a connection to the camera’s power and sync system.

BatteryOne power source the group was interested in using was watch cell batteries. These batteries are utilized in many applications of this magnitude where a small, simple task needs to be executed by a logic board. These batteries are moderately easy to find and replace. The only downside is that these batteries can be expensive and if the battery runs out in a remote area, a replacement can be harder to acquire as opposed to plugging in and recharging. That’s where the second option comes in: rechargeable batteries. If the group can find a small enough unit, (which exists, because the iPod Shuffle is smaller than the group’s projected unit size and that battery lasts for 20 hours) the group should be able to power the device for long enough to be a viable product. The upside to this is there is no need to replace batteries and if the device runs out of power you are only limited to the nearest power outlet or recharging unit. The downside is this may increase the bulk of the unit to accommodate for the battery itself and the external port required to provide power to the unit. There are many resources available that explain the technology available in many form factors of battery types.34

2 http://www.edn.com/article/509352-A_simple_calibration_for_MEMS_gyroscopes.php3 http://www.calvin.edu/admin/av/Battery_Guide.pdf


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http://www.calvin.edu/admin/av/Battery_Guide.pdf

http://www.edn.com/article/509352-A_simple_calibration_for_MEMS_gyroscopes.php

http://www.edn.com/article/509352-A_simple_calibration_for_MEMS_gyroscopes.php

LEDs Two red and one green LED light will reside on the microcontroller and will light up according to the programming which will be discussed in the technical section. A fiber optic wire will then be run into the viewport from these LEDs so that the user will be able to see which lights are lit.

Putting it all TogetherThese 5 major components will work together in harmony to achieve the desired effect. Figure 2 shows a simple block diagram showing the communication paths in which each component “talks” with one another. The microcontroller and gyroscope communicate on a 2-way street, meaning that components talk to each other frequently. The battery and Hot Shoe serve as inputs into the microcontroller. The LED will be the microcontroller’s only output and will serve as the main indicator for the user.

Figure 2 - Functional Block Diagram

4 http://www.ece.gatech.edu/academic/courses/ece4007/08fall/ece4007l01/al2/docs/LiIon.pdf


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http://www.ece.gatech.edu/academic/courses/ece4007/08fall/ece4007l01/al2/docs/LiIon.pdf

http://www.ece.gatech.edu/academic/courses/ece4007/08fall/ece4007l01/al2/docs/LiIon.pdf

Technical DescriptionThis section will cover the technical aspects of each component including the component’s individual aspects, communication with other components and specific products chosen to be used in the project.

MicrocontrollerThe microcontroller will have several responsibilities. First, it must be able to interface with the signal output of the Hot Shoe port on the camera. Second, it must have enough outputs to support 3 LEDs. The microcontroller must do all of this while consuming very little power and being small in size. As mentioned, this product will have to sit atop the camera and fit underneath the pop-up flash. Keeping the camera light is a top priority. For purposes of developing a project where the code will constantly be tested and debugged, EEPROM or flash memory is a must. Other forms of memory are not ideal for this type of development. The gyroscope will be in constant communication with the microcontroller and analyze its readings.


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Figure 3 provides a glimpse into the software logic that the microcontroller would follow:

Figure 3 - Software Block Diagram

The software will determine if the Hot Shoe is active by detecting whether or not a signal is being given to it. If there is no signal, the program will end. If there is a signal, the microcontroller will wake up the gyroscope, which will begin to take readings. The microcontroller will then proceed to take these readings and compare them to a preset “zero”. Based on which way the numbers vary, the microcontroller will output a signal to the appropriate LED (left LED


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for a left tilt, right LED for a right tilt). It will then retake the readings until camera is level. At this point the software will go back to the original Hot Shoe reading loop.

Figure 4 shows how the microcontrollers I/O ports will be utilized by each component.

Figure 4 - Microcontroller Port utilization

Three output ports will be used for LED lights. These will need to be digital ports. The Hot Shoe will also utilize a digital port. The gyroscope will most likely utilize an analog port. This further constrains the choice of microcontroller to ones that offer both analog and digital I/O ports.


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The group will face a tough decision: which microcontroller to choose? There are so many microcontrollers out there; some specialized, some for general purposes. Does a microcontroller already exist tuned to the group’s needs? Research provided some metrics to look for when trying to find a microcontroller. One place to start is power, or more specifically, static and dynamic power dissipation. These two metrics address the power consumed during a typical application. Static power is how much power is consumed when the device is idle. This is crucial because the Hot Shoe only outputs so much power. The group must choose a microcontroller that doesn’t consume too much power, or an external power source may need to be implemented. Wakeup time is crucial. The device must work in concurrence with taking a picture, which is for all intents and purposes, a split second event. If this cannot be done due to limitations of the Hot Shoe, that means the device must be constantly on and monitoring the level of the camera.5

GyroscopeUseful information about the proposed gyroscope can be found in the footnote below.67 It is a single axis MEMS gyroscope that was chosen for its high sensitivity, small physical size, and affordable price. It is manufactured by STMicroelectronics (part number LY503ALH, mouser.com part number 511-LY503ALH). More technical information about gyroscopes will be discussed in detail with reference to the gyroscope actually chosen by the group later in the report.

Hot ShoeFlashes use their own power supply in order to supplement the brunt of the flash power, but the voltage arc through the contacts gives the flash a jump-start and signaling point to discharge. The group’s device hopes to use this source of energy to serve as a “wake-up call” for the device. Figure 5 shows that the Hot Shoe port has a universal specification for sizing and contact points as provided by ISO 518:20068. Access to this standard would be necessary in order to continue on with the project and further the integration with the standard. There are references online indicating the pin arrangement9 and how power is transferred through the system, but no specifics are given as to what kind of voltage passes through the contacts.

5 Bitton, s6http://www.mouser.com/ProductDetail/STMicroelectronics/LY503ALH/? qs=sGAEpiMZZMskzhF9uAtig0PaRHy2pb49xlMQRuW%252bj2U%3d7 http://www.st.com/stonline/books/pdf/docs/15799.pdf8 http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=363309 http://www.mhohner.de/sony-minolta/flashcomp_techref.php


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http://www.mhohner.de/sony-minolta/flashcomp_techref.php

http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=36330

http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=36330

http://www.st.com/stonline/books/pdf/docs/15799.pdf

http://www.mouser.com/ProductDetail/STMicroelectronics/LY503ALH/?qs=sGAEpiMZZMskzhF9uAtig0PaRHy2pb49xlMQRuW%252bj2U%3D

http://www.mouser.com/ProductDetail/STMicroelectronics/LY503ALH/?qs=sGAEpiMZZMskzhF9uAtig0PaRHy2pb49xlMQRuW%252bj2U%3D

Today, though, the Hot Shoe is used as a proprietary port by camera manufactures to connect in-house flash systems. This makes the project somewhat more difficult. Coordination with specific

manufactures will be necessary to learn about how power is used within their implementation of the Hot Shoe system. Access to ISO 10330:199210 will also be necessary to learn about the minimum requirements of ignition circuits through the Hot Shoe port. This standard will show what the minimum amount of power is that goes through

the port. Using this, the group can, determine the power requirements for the unit they are developing. By coordinating with the manufactures, the group can also tap into the auxiliary contacts on the Hot Shoe to gain continual power input.

While the group has, after research, leaned towards an external battery source; the group feels that some sort of charging system using the Hot Shoe can be possible. Unfortunately, access to such documentation was not available for this project. The group also could not ascertain information with 100% certainty that a pass-through Hot Shoe port is possible.

For the purpose of this project, the group used Canon’s Hot Shoe configuration setup for research purposes. This company’s pin-out is the

10 http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=18381


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Figure 5 - ISO 518:2006 Hot Shoe Port

http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=18381

http://www.iso.org/iso/iso_catalogue/catalogue_ics/catalogue_detail_ics.htm?csnumber=18381

most symmetric and similar to the original ISO specification. The reported voltage from many independent sources11 is 5V from the X-sync contact (the largest, circular, center contact). According to this source, it seems that the Hot Shoe supplies a constant voltage of 5V through the X-sync and drains the voltage supply during the shutter discharge and power recycle.

The Hot Shoe port has to be tested for power output due to there being no resources available to see what kind of voltage this port develops. After multiple tries, the group was able to find a contact on a Canon Hot Shoe that outputs voltage at the half button-press and continue to provide a constant voltage 5-6 seconds after release of the button. This port is the data transfer port that is driven by the flash module. The group determined that it provides this voltage to sync the flash module with the camera and drive it to check the conditions of the photograph to set things like ISO, shutter speed and aperture correctly. This would be extremely useful for the project seeing as the device only needs to be on when a user is moments from snapping a picture. The problem with this is that the voltage is very minute: about 11.5mV (this was measured by the group manually as there are no resources available that indicate this value). This would not be enough to power the unit on-demand to check for a level picture. But, this voltage can be used as a trigger to activate the unit from a sleep mode. It is best for the device to remain off until it needs to be used to conserve battery life. So, the device will use this port to awake the device from a sleep state. Now, the device needs a viable power source to run the device.

Putting it all TogetherThe paper has discussed each individual part in detail and has given some inkling as to how all the parts work together. Here, the group will discuss technically how all the parts communicate. Figure 7 shows a color coded block diagram that describes how each part communicates with each other. To clarify, the purple block is a gyroscope and microcontroller joint function. The yellow blocks are Hot Shoe and microcontroller joint functions.

11 http://kzar.net/wiki/Photo/CanonE-TTLProtocol


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– Canon Hot Shoe Port

http://kzar.net/wiki/Photo/CanonE-TTLProtocol

Figure 7 - Hardware Communication

The camera system starts off by constantly awaiting a signal from the Hot Shoe sync port. If there is no power coming from the port, then the processor stays in a sleep-state and no actions are taken. If there is power coming from the port, the processor wakes. The processor then allocates power to the gyroscope and it proceeds to feed real-time data to the processor. The processor then interprets these readings and compares them to the level-state hard-coded data. If the processor’s comparison yields a level result, a power signal is sent to keep on the center LED. If the comparison yields that the device leans to the left, a power signal is sent to the left LED.


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This LED remains on until the user rotates the device to center or too far to the right. If the comparison yields that the device leans to the right, a power signal is sent to the right LED. Likewise, this LED will remain on until the user rotates the device to center or too far to the left. LED displays will be real-time in relation to the real-time data being provided by the gyroscope. When the device stops sensing the power from the sync port, it will go back into sleep mode to conserve energy.

The sync port’s power supply is directly proportional to the status of the shutter button. If the shutter button is held in a half or full-press state, power will continue to be provided to the sync port but once the button is released, there is a 5 second delay before power is cut to the sync port. But, the device’s functionality has nothing to do with the status of the shutter button. It depends solely on the status of the sync port, this just happens to coincide with the status of the shutter button.

Performance ExpectationsThe group has addressed some practical constraints in the creation of this product. The product must be small enough to fit in the space below the pop-out flash that a lot of cameras utilize. The product must have a simple system to indicate the orientation of the camera. A 3 LED system indicating level, off right or off left will be used. The product must utilize as little power as possible in an effort to keep up product longevity without having the need to replace the battery. The product’s microcontroller must have a sleep mode and a short sleep to wake mode activation time. The product is intended to be used more for snapshots or nature vistas rather than spontaneous point and click photos, so the time in which the microprocessor takes to wake does not necessarily have to be the fastest available on the market. In order to account for all of these demands, the group had to choose which products on the market would fit.

The ArduinoAfter doing some research, the group found that the Arduino line of microcontrollers would work best. The sheer flexibility provided by this line of microcontrollers is appealing, and one of them surely can provide all the needs for this project. The Arduino is open-source hardware. Anyone can download the design files and make their own variations. There is a very specific size constraint for the group’s project, and two particular Arduino models, the mini or mini pro, are ones that can satisfy these constraints. These models would need an


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additional circuit that latches onto the mini in order to interface via a wire to a computer.

Figure 8 - FTDI Basic Breakout

Figure 9 - Arduino Pro Mini

Figure 8 shows the FTDI Basic Breakout, a small chip that goes on the pins labeled Programming Header in Figure 9. This provides the necessary interface to communicate with a computer to upload code12. The Arduino utilizes its own custom programming environment and is compatible with Windows, Linux and Mac. The Arduino Mini runs at 8MHz with an external resonator. It is a low voltage board that is perfect for powering devices such as a gyroscope. It has a USB connection to program the board and has a 150mA output. It’s most important feature is its size, at .7x1.3” it is among the smallest boards available, which is one of the group’s biggest constraints in choosing hardware. It also weighs less than 2g, which won’t add much to the weight of the camera. The Arduino platform itself is very popular amongst the tech community and is used in many DIY projects and products. These products vary widely and the Arduino is considered to be a revolution in open

12 http://www.sparkfun.com/tutorials/244


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http://www.sparkfun.com/tutorials/244

sourced hardware. Its platform for coding and interface is very easy to use and robust.

Figure 10 shows the technical schematic for the Arduino Pro Mini.

Figure 10 - Electrical Schematic of Arduino Pro Mini

GyroscopeThe gyroscope the group decided on is the LY503ALH by STMicroelectronics. It is an accurate, small MEMS gyroscope with a low power consumption and high shock and vibration survivability. It consists of a sensing element of a single driving mass which is kept in continuous oscillation and that reacts to changes in the angular rate based on the Coriolis principle. It is capable of measuring the absolute angular rate around a single-axis, which is output as an analog voltage. Specific specifications of interest to this project are the physical size (5x5x1.5mm), the measurement range (+/- 120°/s or +/- 30°/s at 4x amplification), the sensitivity (8.3mV/°/s or 33.3mV/°/s at 4x amplification), supply voltage (2.7-3.6V), and supply current (5-5.5mA when on, 1-5uA during power-down). For the


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LY503ALH’s pin out, mechanical characteristics, and electrical characteristics, see the tables below:


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This gyroscope in particular was chosen for a combination of reasons. First, it was one of the smallest ones that could be found, which will help the group in keeping the physical dimensions of the overall product as small as possible. Also, the voltage requirements would work well with the microprocessor that was chosen (gyroscope needs 3V, microprocessor comes in a 3V model) and the current requirements were very low which will maximize battery life (gyroscope’s maximum draw is


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5.5mA). The fact that this is a single axis gyroscope is acceptable. At first, the group considered providing two axis sensing, but figured only one axis was necessary as the second would only be a distraction in most cases. The group figured that in real life applications, two of the three dimensional axes would not be able to be changed without changing the content of the photograph being taken, so the end user would only be concerned about the one remaining axis when it comes to being level. Since the microprocessor has both analog and digital inputs, the LY503ALH’s analog output will not be a problem as it can interface with the Arduino processor just fine.

One problem of the LY503ALH, and in fact gyroscopes in general, is that it outputs an angular rate measurement instead of an angle measurement. Since this is a problem encountered with all gyroscopes, measures have been developed to not only convert the rate measurement to an angular one, but also to ensure the accuracy of the resulting conversion. The conversion itself is nothing more than basic calculus. To change the measurement from an angular rate to an angle, all which is required is an integrator circuit. However, in practice this conversion can be tricky because any inaccuracies (bias errors, random errors/noise, etc.) in the rate measurement get amplified. The simplest method to deal with these errors is to individually calibrate each gyroscope. With proper calibration, MEMS gyroscopes can reach less than 1% error rates when measuring absolute angles. This is not ideal for full manufacturing as the time and labor requirements when scaled to full manufacturing levels would become too great. Other proprietary measures have been developed to combat this problem, but are outside of the scope of our research at the present time. However, individual calibration would be acceptable for prototyping.


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Critical Evaluation

The “Good”The product is needed in the market; no other products provide the convenience of the group’s proposed product. The product allows the use of other accessories on the camera. The product is cost effective and would be cheap enough on a production scale to sell at a reasonable price for both serious and above average camera users. The group has decided to do the initial calibration at the factory, eliminating potential user error in calibrating the device.

The “Scary”For the particular camera the group is aiming to fit this device, there could be a problem trying to fit the device on top of the camera. The camera has a pop-up flash which only allows about three quarters of an inch of space to situate a microcontroller on top of. The product will need an external source of power. The camera’s ability to stabilize itself is based solely on the user’s initial calibration. If this is done incorrectly, the product may not work. If the Hot Shoe pass through cannot be executed, other accessories cannot be used. This may also cause deteriorated flash output.

The “Fun”Moving forward, the overall product idea is fairly simple, so it should leave plenty of time to troubleshoot, tweak and add functionality. One student suggested the viewfinder be able to be shifted back and forth to allow for more universal use. Also, the space and power requirements should be a fun challenge for the group. Finally, it will be rewarding to be working on a project that not only has an established market that would actually use the product, but that the group themselves would use in the real world.

FundingThe group has researched the idea of this project and the costs associated with it. We have determined that there is very little in the way of production costs. Most of the parts are off the shelf and can be combined quickly. The software is developed in-house and uploaded to the microcontroller at the plant and centered. The only part that has to be developed and created custom is the plastic housing that all the parts will be put into. This can be mass-developed overseas in a manufacturing plant owned by another company.In order to actually acquire the funding needed to develop this and produce it, the group would seek out the assistance of an accessories


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manufacture in the photography industry. A couple companies of note are Tiffen, Targus, Kodak, and Energizer. All of these companies are well-known in the industry to create camera accessories and have established manufacturing roots and endless R&D budgets. Another avenue that the group could look into is producing the accessory directly with the camera manufactures – Nikon, Canon, Sony, Pentax, etc. These companies could use their own specifications and create devices custom fit to their camera bodies. All that would have to be done by the group is to sell the idea and help with development.For something this cheap and an idea this simple to execute, not many camera accessory companies would turn away an idea like this for what we believe to be an extremely marketable idea. One other avenue the group could explore is independent funding from private investors – people who are stockholders in the photography industry already. These investors could assist in production costs or be involved in a cut of the budget along with an accessory manufacture.


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SummaryOverall, the group believes this could be not only a viable senior design project, but also a viable product to take to market. There is enough complexity to warrant it being a year-long project, and it touches on many of the most important issues a Computer and Electrical Engineering major will deal with (using electrical sensors, interfacing inputs and outputs with a microprocessor, etc.). Also, because of the low price to produce and existing demand for this product, there is always the possibility of taking the product to market. If the group goes forward with this, they have completed much of the necessary background research and should be able to jump into the prototyping phase almost immediately, however all of the problems are far from being resolved. Meeting the size and power requirements will be difficult, and will probably be where the bulk of the design problems crop up. Also, the group will need to decide to what degree the product will be universal, i.e. whether it will work with one SLR camera, a handful of SLR cameras, or as many as feasibly possible. This will not affect the electrical or computer design per se, but will dictate the mechanical design which will in all likelihood have an effect on the former. Overall though, the group has enjoyed working on this project so far, and if they have the opportunity to move forward with it, would enjoy being able to work on something that they themselves would like to have and be able to use in their everyday lives.


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VitaThomas Dabay is a 4 out of 5 junior originally from Roanoke, VA. He spent the first two years of his Stevens career as a Mechanical Engineering major before seeing the light and switching to Electrical Engineering. During his tenure at Stevens, he has completed three separate cooperative education terms, one at each of the following: Mindray DS in Mahwah, NJ (spring ’09), NAVAIR in Lakehurst, NJ (fall ’09), and Gyrus ACMI in Stamford, CT (summer ’10). He will now be taking his final summer off before focusing on senior year.

Kris Engel is a 4 out of 5 junior originally from West Hempstead, NY. He originally chose to go for a Computer Engineering major, before deciding to explore the Electrical Engineering side of things in 2010, and quickly switching back to Computer Engineering. While at Stevens, he has completed two cooperative education terms, one at Colgate in Morristown, NJ (Summer-Fall ’08) and one at Mindray in Mahwah, NJ (Fall ’09). He will be returning to Colgate for a part time position over the summer and fall of ’11, while also taking classes part time to complete his degree.

David Quirk is a 4 out of 5 junior originally from Oak Ridge, NJ. He has been a Computer Engineering major since his first year, and has done three cooperative education terms. The first two were spent at Calyon (Credite Agricole) in New York, NY (spring ’09 and fall ’09), while the third was at Verizon in Bedminster, NJ (fall ’10). Over summer ‘11, he will be returning to Verizon for another cooperative education term, after which he will spend his last two semesters at Stevens finishing his Computer Engineering course work.

Bibliography


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