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1. are not available the timer information will be stored on the memory card in place of the GPS information Since it will be unknown where this impact occurred the software estimates the location based on stored clock information Accelerometer The PIC contains several peripheral options one of which is a built in ADC Analog signals from the accelerometer vary based on acceleration The ADC of the PIC was used to measure the outputted information The operating manual of the PIC was the only resource needed to interface the accelerometer with the microcontroller Registers were set to enable analog to digital conversion for the pins attached to the accelerometer The only issue encountered in interfacing the accelerometer was a mistake made in deciding which pins to use Some of the originally selected pins were used by the debugger which caused the implementation to fail This was remedied by using different pins Once the ADC was working properly a procedure was written to determine if an impact was beyond a threshold value A running average of the previous twenty values was used to determine the standard force This allows subtle movements over a long period of time to not be recorded as impacts When a movement causes a change of 20 or more above the threshold an impact is recorded GPS Device Another peripheral option present on the PIC is the ability to communicate using the UART protocol To allow communication between the GPS and th
2. card LM882 voltage regulators were chosen because of their low idle current and large input voltage range Development Process and Issues After the decisions were made about which components would be used in the project different parts were interfaced to the PIC The clock speed and power consumption of the PIC was reduced by turning on the low power RC oscillator The accelerometer was interfaced to the PIC by changing the appropriate register values and writing a procedure which could measure the output values Communication between the PIC and the GPS device was established by changing appropriate registers and writing a procedure which would store the received values In other words the microcontroller s A D registers were set to measure output values from the accelerometer To do this the registers were set to identify the pins being used on the PIC the voltage reference for the internal A D the analog conversion clock and that the output would be represented as an integer The UART Registers of the microcontroller were set so that the microcontroller would receive and transmit data through a UART interface The registers were also manipulated to set the baud rate of the transmitting and receiving lines along with the stop and parity bits and interrupts The impact monitor and software were developed in parallel The software converts the information into a kml file which can be read by Google Earth Impact information is parsed and
3. power consumption was to turn off or disable power hungry peripheral devices when they were not in use Together the GPS unit and memory card draw 80 to 100 mA The microcontroller and accelerometer draw a combined 1 45 mA when using the LPRCO To create the 3 3 V source needed to supply all components two LM882 voltage regulators were used A single voltage regulator and a transistor switching scheme was used to turn on and off the GPS and memory card This combination led to write errors in the memory card Using a separate voltage regulator for the memory card reduced the number of write errors most likely because it isolated the transmit and receive signals from the noisy GPS unit This setup also reduced the idle current from 2 6 mA to 1 45 mA Power measurements were made using a voltmeter and an ammeter Both were attached to the input voltage rail of the device At full power all components are operating and the device draws an average of 100 mA When the device is listening for impacts it draws 1 45 mA Ina worst case scenario the device operates at full power 10 of the time If the device operated 10 of two months it would run for 144 hours Assuming each impact takes 2 minutes of operating time the device could measure 43 200 impacts Table 1 Battery Life at 90 Idle Capacity mAH Life T Hours Life T Days AA 2 890 255 6 10 7 C 8 350 738 6 30 8 D 20 500 1 813 4 75 6 Table 1 shows the projected maximu
4. AC 2010 1383 AN INDUSTRY SPONSORED CAPSTONE PROJECT A STORY OF SUCCESS Khalid Al Olimat Ohio Northern University O American Society for Engineering Education 2010 ss si oBeg An Industry Sponsored Capstone Project A Story of Success Abstract This paper presents a capstone project that has been sponsored by American Electric Power AEP AEP like other companies relies on shippers to move equipment long distances Sometimes during these trips the shipped object is damaged causing financial losses AEP requested a device which monitors when and where damages occur A device was designed which gives AEP this capability Since the duration of a shipment may be up to two months the device must contain an adequate power supply The device records multiple impacts as well the location date and time of each impact It contains a timer which can be used to record each impact in the event that Global Positioning System GPS satellites are not available Collected data is written to a memory card so it can be retrieved using a PDA or laptop The monitoring device consists of a Programmable Interface Controller PIC an accelerometer a GPS receiver a memory card slot and other electrical components When an impact occurs the PIC logs the value of the acceleration and activates the GPS device to determine the time and the device s present location If the GPS device is unable to receive a signal the PIC will record the time of the imp
5. BA Store to MMC Above Bellow Average lt ie and Resume es ZL SG SL oped Appendix B Google Earth Display Example Date dd mm yy 17 04 09 UTC 00 45 01 232 Impact X Direction 0 07 s Impact Y Direction 1 15 g Impact X Direction 0 29 g eo E se stek ae lt m p Vo II g Impact 3 z 4 MA ts f 8 sg g1 oBeg
6. Low Low The PIC24FJGA002 is a 28 pin microcontroller It consumes less than 1 mA when running from a low power RC oscillator LPRCO and is also capable of running at speeds up to 32 MHz For the purposes of this project the PIC is driven by the LPRCO when monitoring the accelerometer When an impact occurs the clock speed increases from 31 kHz to 8 MHz to allow communication with peripheral devices The microcontroller has two SPI modules two UART modules a 10 channel 10 bit analog to digital converter and 16 reprogrammable pins It contains 22 KB of program memory At 1 92 per chip it provided the best value Accelerometer One of the most crucial components in the impact monitor device is the accelerometer An accelerometer is a device that can be used to numerically measure the accelerations acting on an object The accelerometers considered for this project output an analog signal with a voltage proportional to the acceleration experienced In the impact monitor these analog signals are sent 9 GGI S oBeg to the analog to digital converter ADC on the microcontroller where they are converted to numerical values and stored on the memory card It is essential that the impact monitor make use of an accelerometer that measures acceleration on three axes since impacts may occur in any direction In addition to having the ability to measure acceleration on multiple axes other requirements need to be met The accelerometer m
7. act The PIC sends this information to the memory card A software package developed to work with this device enables the end user to view a map indicating where each impact occurred The impact data is retrieved by inserting the memory card into a PC or PDA Information about the strength and time of each impact is displayed on a map The design project has won first place as the best design project at Ohio Northern University ONU and second place in the IEEE Student Activities Conference 2009 The paper presents the technical content of the design the assessment of the design with respect to ABET criterion a k and the advantages of and recommendations for industry sponsored projects Introduction The senior design course also called senior capstone design project is an important component of engineering curriculum worldwide The course is a senior level course with a common objective which is to mainly allow students to reinforce their technical skills and to integrate and apply them to solve engineering problems ABET states the definition of engineering design as Engineering design is the process of devising a system component or process to meet desired needs It is a decision making process often iterative in which the basic sciences mathematics and engineering sciences are applied to convert resources optimally to meet a stated objective Among the fundamental elements of the design process are the establishment of objectives an
8. arket Although people have transported goods for thousands of years there are still areas of transportation that can be improved In an effort to attract a larger share of the transportation market shippers sometimes decrease quality to increase efficiency and cause damage to shipped goods Presently shippers and their clients must come to an agreement before the product is shipped An insurance policy is negotiated beforehand based on whether or not the cargo arrives damaged or not damaged There is currently no way to prove that the damage occurred when the shipper had possession of the cargo System Specifications Specifications given by AEP were used to measure the success of the system at the completion of the project The following specifications outline the operation and capabilities of the designed system e The device must record up to 1000 impacts as well as the location date and time of each impact e The device must contain a real time clock which can be used to record each impact in the event that GPS satellites are not available Once satellites are available the device must synchronize the real time clock and previous readings with the current satellite time e The device must be able to store information by writing it to a memory card that can be read using a PC or PDA e The device must be able to operate on a single power supply for at least two months Design Deliverables AEP requested a list of specific items t
9. ate a bulkier device The cost of the device must be low Other devices that record impacts cost in the range of a few hundred dollars To remain competitive the final cost of the device must be less than 200 If the device proves to be useful AEP may seek to mass produce it A strategy to reduce the price of the device includes choosing components with multiple purposes The device must be reliable in normal shipping conditions It must be able to survive multiple impacts and still function properly Considerations must be made in choosing the proper container and components to ensure that the device is durable Environmental factors such as temperature and humidity must also be considered in choosing the case and electronic components If the device fails because it is unable to tolerate the normal wear and tear of shipping it will be rendered useless The size of the device must be kept to a minimum for several reasons It will be mounted in shipping containers A large project case could create problems in finding a good place to mount the device If the device is bulky this may create difficulties in maneuvering the goods to be transported into the shipping container To allow for easy transport of the device it must be easy to handle A smaller device would allow a shipment manager to carry several monitoring devices at once Hardware Description The tracking device is made up of a Programmable Interface Controller PIC an acceleromet
10. ct as early as possible If students face any difficulties they will be able to overcome them and finish the project on time Conclusion An industry sponsored senior design project was presented in this paper The experience gained out of the project was presented It is believed that such projects prepare students well to work in the industry The American Electric Power has pointed out on their website that AEP established University Alliance Program and it has resulted in more qualified job applicants with greater technical knowledge which allows them to be productive employees sooner It is also believed that partnering with industry for the senior design course is very beneficial to both the students as well as industry which lead to a win win situation In addition the sponsored senior design projects provide regular opportunities for faculty members to interact with industry Acknowledgement The work that has been performed by Tom Fritz Michael Sherry and John Weeman in the senior design project titled Design of an Impact Monitor Device is acknowledged OL SGL S oBeg References 1 ABET Accreditation Commission www abet org 2010 2 Thomas Fritz Michael Sherry John Weeman and Khalid Al Olimat Design of an Impact Monitor Device Proceedings of the ASEE North Central Section Grand Rapids MI April 2009 3 MR Ford and C Coulston Design for Electrical and Computer Engineers Theory Concepts and Practic
11. ct of engineering solutions in a global and societal context The students strongly believe that it is engineering that changes the world 1 a recognition of the need for and an ability to engage in life long learning The students have shown through the course of the project that engineering is not a learned profession but it is a learning profession j a knowledge of contemporary issues No comments k an ability to use the techniques skills and modern engineering tools necessary for engineering practice The students have used programming PSPICE and other tools to build the device In addition to the above items the ABET requirement of including necessary realistic constraints was also satisfied by this project Advantages and Recommendations Based on the experience gained out of sponsoring senior design projects from industry at Ohio Northern University and at other universities there are similar advantages and recommendationst The noticed advantages of industry sponsored senior design projects are presented in the following list 1 Students are introduced to real world problems and applications in engineering Industry sponsored projects show the real world view of how engineering design is done in industry 2 Students gained knowledge and experience throughout the course and that builds their confidence They interacted with industrial and vendor representatives managed an GI SGL SL oBeg industrial project and achi
12. d criteria synthesis analysis construction testing and evaluation Simply engineering design is the use of theoretical knowledge to bring useful systems to reality The structure of senior design experience varies from one university to another Some universities offer this course as a one semester course and others offer it as a year long course ONU requires students to take a year long three quarters senior design sequence The sequence consists of three courses senior design seminar 2 credit hours senior design 3 credit hours ZGSI S oBeg and engineering technical communication 1 credit hour The list of senior design projects is given to students in the last week of spring quarter of their junior year Students are asked to list their top three choices from the given list The faculty members of the department meet and distribute the projects to students taking into consideration the factors of students choices and their technical abilities to form the senior design teams This ensures that each team has a fair chance of success The team size depends on the project s needs Typically each team consists of 3 4 students One faculty member in the department assumes the responsibility of the senior design coordination The other faculty members serve as team advisors The list of projects consists of both faculty sponsored projects and industry sponsored projects The focus of this paper is on the industry sponsored pro
13. e McGraw Hill 2005 4 Paul Biney Assessing ABET Outcomes Using Capstone Design Courses Proceedings of ASEE Annual Conference and Exposition 2007 5 James Widmann Enhancement of Capstone Industry Sponsored Senior Design Projects through Team Based Product Realization Activities Proceedings of the ASEE Annual Conference and Exposition 2008 6 Ken Christensen et al Partnering with Industry for a Computer Science and Engineering Capstone Senior Design Course Proceedings of ASEE Southeast Section Conference 2003 7 A Otieno and C Mirman Engineering Technology Capstone Experience An Industry Based Partnership Journal of Modern Engineering V3 No 2 Spring 2003 Appendix A Impact Monitor Flow Chart Reset m NA Tum GPS OF Fie v Initialize T Ports YES Create Array with po kar Coordinate and A 30 Initial di oe e 15 Read Readings Information NO eee d v ne 5 NO Readings ra YES into Array Write Number _7 Information _ of Impacts to Valid lt Y Sector 520 TR Take 8 Hour Reading Extract m Wee P Coordinate g9 rite Create Information pay Information Array F Enable GPS nable Readings o Sector 520 i Read 1000 and Get J i Coordinates A Power OFF Pi Na MMC a _ Current Reading gt 20 Bi Spa
14. e PIC the UART module was initialized The main reference was the PIC s data sheet which showed the appropriate registers to change to enable UART communication In UART communication it is necessary to specify the bit rate parity bits and stop bits This information was found in the GPS module s data sheet and was set in the PIC s registers The GPS module s data sheet indicated that the device transmitted with no stop bits and no parity This configuration is not possible and that proves the documentation was incorrect and corrupted The correct configuration was found by assuming the most common configuration of one stop bit and no parity The data rate was found to be 9600 bps by trial and error A procedure was written to capture and process the received GPS data into a string which showed present position time and date The setup was tested and successfully captured the correct data Memory Card Data storage is an integral part of this project a relatively small amount of impact information must be stored on a non volatile memory device until it is retrieved So far this has been the most challenging part of the project Several example projects were considered to interface the PIC with an MMC card Most of these example projects modify the FAT file system present on MMCs None of the examples worked with the device s setup The other option was to store data in a raw format on the card Writing data in the raw format is less desi
15. e team conducted research on the basic engineering and scientific principles technologies and existing solutions related to the given problem They became experts on the technology implemented in their solution to the problem 3 Requirements Specifications The team focused on what the system must do and worked toward this objective 4 Concept Generation students proposed many solutions but they developed the best solution among all that best met the requirements and satisfied the constraints 5 Design phase the team developed a technical solution produced a detailed system design All major systems and subsystems were identified and described using an appropriate model 6 Prototyping and Construction phase the team constructed and tested different elements of the equipment impact monitor 7 System Integration the team integrated all of the subsystems together and produced a complete working device as needed 8 Maintenance Phase the team developed a user manual explaining the device s troubleshooting ABET Criteria The presented project fulfills ABET criteria There is a clear guidance for what ABET would like to see in a senior design course According to Criterion 3 the characteristics necessary for well prepared graduates include a an ability to apply knowledge of mathematics science and engineering The students have applied their knowledge in these areas when they analyzed their designed device b an ability
16. e was to store the impact information to a memory card for later retrieval by a PDA or computer The device is capable of writing to a memory card which is readable by a developed software package The device was to have a battery life of at least two months Under worst case conditions the device can sustain itself for 75 6 days Although the major specifications of the project have been met a suitable container must be chosen for the device The best off the shelf potential containers for the device are outside junction boxes These boxes are designed to shelter electrical components and provide an environment free of humidity So the container is selected and the device is housed The designed device is delivered to AEP EL GGL SL oBeg Discussion of the Design Process Per ABET definition Engineering design is the process of devising a system component or process to meet desired needs It is a decision making process often iterative in which the basic sciences mathematics and engineering sciences are applied to convert resources optimally to meet a stated objective Among the fundamental elements of the design process are the establishment of objectives and criteria synthesis analysis construction testing and evaluation The following are important steps in the design process 1 Problem identification AEP came with a problem to be solved Students identified the problem and the customer needs 2 Research phase th
17. ecords multiple impacts as well as the location date and time of each impact It contains a timer which can be used to record each impact in the event that Global Positioning System GPS satellites are not available Collected data is written to a memory card so it can be retrieved using a PDA or laptop The monitoring device consists of a Programmable Interface Controller PIC an accelerometer a GPS receiver a memory card slot and other electrical components When an impact occurs the PIC logs the value of the acceleration and activates the GPS device to determine the time and the device s present location If the GPS device is unable to receive a signal the PIC will record the time of the impact The PIC sends this information to the memory card A software package developed to work with this device enables the end user to view a map indicating where each impact occurred e ga S oBeg The impact data is retrieved by inserting the memory card into a PC or PDA Information about the strength and time of each impact is displayed on a map Problem Statement The economy of the world is currently in a state of change Demands are rapidly increasing as previously third world countries develop into sizeable economies To take advantage of new markets manufacturers must learn to cheaply manufacture a product at point A and ship it to point B Companies must explore alternative methods of improving efficiency to remain competitive in the world m
18. er a serial GPS receiver a memory card slot and various analog components The device will continuously monitor for impacts If an impact occurs the accelerometer registers the acceleration of the impact and sends it to the PIC The PIC then logs the value of the acceleration and activates the GPS device to receive information about the time and location of the impact If the GPS device is unable to receive a signal the PIC logs the time of the impact from an on chip real time clock RTC The PIC sends this information to the memory card Appendix A shows a flow chart of the operation of the device G GGL S oBeg The software package for the device can be loaded onto a PDA or personal computer It will enable the end user to view a map indicating where each impact occurred The software will also display information about the strength and time of each impact Programmable Interface Controller The Programmable Interface Controller PIC is an integral part of the device It is responsible for communicating with peripheral devices that monitor impacts obtaining location and time information and storing information to a memory card Based on these communication needs the PIC needs to be capable of interfacing with two different protocols universal asynchronous receiver transmitter UART and serial peripheral interface bus SPI The PIC must also consume a minimal amount of power To ease development the microcontroller should support a hig
19. eved success by completing it through both well organized work and their ability to handle the pressure of time and budget constraints 3 Students learned the importance of recording the meeting minutes and documenting all activities throughout the course 4 Students developed team management and leadership skills in addition to improvement of their written and oral communication skills 5 The tremendous variety of issues they faced on their project gave them a chance to put their engineering education to work Universities that would like to partner with industry for senior design projects are recommended to take the following points into consideration to ensure that projects will be completed on time and functioning as desired These will lead to student success 1 Students must realize that team work and group dynamics are an important part of the experience 2 Participating industry are expected to continue sponsoring projects if they see a pay off which is a well organized work and a completed design 3 Sponsored projects must have clear definition and specifications 4 It is important that there is clear communication among the student team faculty advisor and the industrial representative 5 Students must write weekly progress reports agendas signed time sheets and document all activities This will keep all members of the team synchronized in terms of understanding where they are in the design process 6 Start the proje
20. from the satellite signals Few stand alone GPS devices were found that could be used in this project Nearly all other choices required the purchase of a separate smaller antenna The EM 408 GPS receiver was chosen because it had a relatively small size and an internal antenna Memory Card The memory card for the device is used as a storage device for impact information obtained from the accelerometer and the GPS device AEP personnel will be able to retrieve the data from the memory card by inserting it into a PC or PDA A developed software package is able to retrieve and display the required data MultiMedia MMC and Secure Digital SD cards are the two popular devices used for flash memory storage Both are capable of using the SPI protocol to communicate with a microcontroller Although both formats are usable MMC was chosen over SD because it was less expensive Z SG st oBeg Power Supply Since the device will be mobile it will require a battery to provide power for as long as two months The power supply provides a voltage source for each component All components use 3 3 V input voltage Based on current measurements which will be described later it was concluded that four D cell batteries connected in series would provide an adequate power supply To stabilize and step down the voltage from the batteries two voltage regulators were used One was used to power the PIC and GPS device and the other was used to power the memory
21. her level programming language Communication capabilities are of utmost importance in this project If the PIC is not able to interface with each peripheral device successfully one or more goals of the project will not be completed At the same time the PIC must be as efficient as possible A PIC with sufficient communication capabilities normally has a larger pin count and consumes more power since it has extra features that are not needed On most PICs the function of each pin is predetermined with different functions sometimes requiring the same pins There are two ways to meet the communication needs for this project choose a PIC with many input output pins or choose a PIC with the capability of switching the communication protocol used by each input output pin The second method was chosen because it allows the device to consume less power and be contained within a smaller package Microchip Inc makes a wide variety of microcontrollers and was chosen to supply the PIC for this project because of its range of development tools There are multiple devices that may be able to accomplish the goals of this project but the chosen PIC is from the PIC24F family Table 1 shows the PIC families that were considered for this project Table 1 PIC Families Family Primary Purpose Architecture Sensor Flexibility Memory Capacity PIC24F Sensor 16 bit High High dsPIC30 Motor Control 16 bit Medium Medium PIC18F Multi Purpose 8 bit
22. jects Typically the industry sponsored projects are more challenging because the problems offered by the industry are real world and practical problems In addition since the partnering industry provides financial support they are interested in the project outcome ONU became a member in the American Electric Power AEP University Alliance Program in 2007 AEP has sponsored seven excellent projects in the past 08 09 academic year at ONU The author advised the project presented in this paper The project entitled Design of Equipment Impact Monitor was a complete success by all measures It won first place among all senior design projects in the ECCS department at ONU and second place in the 2009 IEEE Student Activities Conference In addition to the project technical design a discussion of the design process the assessment of the design based on ABET criteria advantages and some recommendations are presented Design of Equipment Impact Monitor Overview American Electric Power AEP is a power utility company based in Columbus Ohio AEP like other companies relies on shippers to move equipment long distances Sometimes during these trips the shipped object is damaged causing financial losses AEP requested a device which monitors when and where damages occur A device was designed which gives AEP this capability Since the duration of a shipment may be up to two months the device must contain an adequate power supply The device r
23. lame on a shipping company if the device showed no damaging impacts occurred Political The device must not output electromagnetic noise that violates FCC regulations Individual peripheral devices meet FCC regulations so it follows that the combination of these devices are compliant as well The device follows local and international laws regarding RoHS compliancy since all components are RoHS compliant Concluding Remarks The purpose of this project was to develop an impact monitoring device capable of recording the acceleration location and time of several impacts This was accomplished by using the given system specifications and required design deliverables to create potential designs Potential components were researched to determine which ones were ideal based on the requirements of the project Once specific components were chosen development began and proceeded until the goals of the project were met A device was built which meets the initial design specifications given by AEP The device was to record at least 1000 impacts It has been tested to record at least 2500 impacts and can potentially record more than 43 000 impacts The device was to contain a real time clock which can keep time in the event that a GPS signal cannot be acquired A crystal oscillator was chosen that is accurate to within 1 minute per year It has been successfully integrated into the circuit design and the microcontroller keeps time as expected The devic
24. m operating time for three types of batteries The D cell batteries provide more than two months of operating time Software Package A software package which displays the impact data graphically was created in parallel with the impact monitor The software is able to read the information stored on the memory card and pin point each impact location using Google Earth Each pin point shows the time date and acceleration value of an impact Appendix C shows an example image produced using the software package and Google Earth The program operates by reading information from the memory card and storing it onto a kml file which can be read by Google Earth In the event that OLSGL SL oBeg GPS information was not available when an impact occurred the location is estimated based on the previous locations and the impact time Budget Expenses have been divided into development costs and the cost of a single impact tracking monitor Table 2 summarizes the hardware and costs needed to complete the project Table 3 shows the cost estimation for a single impact monitor The total cost of the project is 1063 and the cost to build a single tracking unit is 143 Analog components are listed in both cases these components include resistors capacitors voltage regulators antennae and connectors The prototype boards were made and provided by the department s technician The cost of labor was estimated based on the pay rate of 35 per hour The hours
25. o be delivered upon successful completion of the project The following list outlines the items that must be given to AEP Project box containing all components for the impact monitoring device e Packaged software to be installed on a personal design assistant PDA or laptop with a Windows or Linux operating system e Short manual detailing the successful use and assembly of the product e All relevant source codes with instructions for compiling Circuit schematics e Logic block diagrams YSSEL oBeg e Complete schematics for finished device including dimensions and electrical specifications e Inventory list with associated prices for all materials and parts used in the project Implementation Considerations There are several implementation considerations for this project Although these considerations are similar to constraints they provide more specific goals for the design These considerations are power consumption cost reliability and size Power consumption was the most important consideration in the working device The device must consume a minimal amount of power while still allowing it to function properly If the device were to lose power during operation valuable data would be lost Power consumption must also be minimized because the size of the device is limited Specifically the device should draw an average current of less than 15 mA at 3 3 V High power consumption requires large batteries which in turn would cre
26. rable because the card must be formatted before it can be used again The only option was to write a unique MMC driver The driver created is very simple it is capable of reading and writing a single 512 byte data block It was found that a text file created on a formatted card is always stored at the same memory address By writing to the address of the text file it was possible to use the simple MMC driver to write information to a formatted card without manipulating the file system Writing to the memory card without manipulating the 6 GGL S oBeg file system was desirable because it simplified the driver Overwriting the text file data allowed the computer data retrieval program to be simpler because it did not have to find data on a memory card with no file system Power Supply It was possible to make rough power estimations for the end device based on individual data sheets but a better estimation of power consumption was made after the device was built A debugger and development board were used to interface the microcontroller with other peripheral devices Since the device was powered from the computer it was not practical to make power measurements using this setup The move from a debug environment to a standalone battery powered device was not difficult The compiler was changed from debug mode to release mode The microcontroller was programmed and all peripherals were circuited using a bread board The primary means of reducing
27. shown graphically at the site of each impact Programmable Interface Controller One of the main requirements of this project was to have the monitor device consume a minimal amount of power The electrical specifications found in the data sheet for the microcontroller indicated that the PIC would draw less power when operated at a slower clock speed There were two options for changing the internal clock speed of the PIC The first is to prescale the fast internal RC oscillator The second option is to use the internal low power RC oscillator LPRCO Programming the PIC to use the LPRCO presented a challenge since it was the first task with an unfamiliar microcontroller to the team The PIC manual described a process to switch oscillators but all attempts failed when using this method The solution was found by examining an example program The program included a built in command which switched to the desired oscillator To test that the PIC was truly operating at a slower speed a program was executed which pulsed the LED outputs before and after the oscillator change A watch dog timer WDT and real time clock RTC were developed for the device The WDT is used as a fail safe If something were to cause the PIC to freeze the WDT resets the PIC The 8 gg1 g oBeg RTC is used in case valid GPS information cannot be obtained A clock within the PIC synchronizes with satellite time at the first valid GPS fix If an impact occurs when GPS signals
28. the cost of the finished device The amount of parts was minimized using components that serve multiple purposes In order to facilitate easy manufacturing and lower design cost the device contains as few components as possible Integrated circuit IC components were chosen such that a single IC provided several needed features Although similar devices are already available on the market no single device provides the same set of features as the proposed device The designed device competes with these similar devices by having lower final price per unit Sustainability The device is producible with available and easy to obtain resources In the event of a failure the problem is resolvable by replacing only the faulty component Each component is replaceable with standalone and easy to find parts Health amp Safety The device must be restricted to a container such that there are no exposed wires or components A specification plate will be attached to the device with all necessary information such as voltage current and power ratings Additionally warnings will advise the user of possible hazards and inform the user that the device s parts comply with the Restriction of Hazardous Substances RoHS Directive The RoHS directive was originally a law adopted by member states of the European Union It limited the amount of dangerous substances present in electrical equipment The directive is becoming an international standard for prod
29. to design and conduct experiments as well as to analyze and interpret data The students have obtained data from the device to check its accuracy testing it interpreted the data and made the necessary adjustments for the device to function properly c an ability to design a system component or process to meet desired needs YESSS oBeg The students have designed the device based on a given set of specifications and the completed the design as needed d an ability to function on multi disciplinary teams The students have worked well together in this multidisciplinary project They interacted well with the project advisor and with engineers from the industry e an ability to identify formulate and solve engineering problems The students have identified and defined the problem given to them by the industry formulated many solutions and have chosen the best possible solution implemented it and solved the problem f an understanding of professional and ethical responsibility Although this item is usually very hard to assess the students have shown that they worked professionally together and they gave credit to every source that they relied on in solving the given problem g an ability to communicate effectively The students have shown their communication abilities and skills through the written proposal written final report poster presentation and the oral presentations h the broad education necessary to understand the impa
30. uction of new electronic devices Manufacturability In order to facilitate easy manufacturing and lower design cost the device contains as few components as possible Integrated circuit components were chosen such that a single IC can provide multiple needed features By placing all components on a single printed circuit board it is durable enough to survive likely impacts which will be experienced by the device Ethical The purpose of the device is to hold a shipper responsible for damage incurred during shipment The device should be tamper proof so that the data log cannot be manipulated The device has the potential to infringe upon personal privacy by tracking an object without its owner s knowledge Considerations were made to prevent this possibility zk SG s oBeg Environmental To minimize the environmental impact of the device it must consume a small amount of power contain a minimal amount of hazardous chemicals lead arsenic etc and withstand corrosion at high humidity It must also not secrete dangerous chemicals in harsh environments melting plastic in high temperatures Steps should be taken at the design stage to accomplish these goals Social The purpose of the device is to hold shippers accountable for mistakes during shipment This could change the relationship between shippers and their clients Shippers are likely to be more careful and cautious with shipments Their clients may reconsider placing b
31. ust have low power requirements be reasonably priced and withstand the forces of a journey The ADXL family was recommended by AEP Two other accelerometers were considered the SCA3000 DO1 and the MMA7260Q All measure acceleration in three dimensions but the ADXL330 outperformed the other accelerometers in terms of sensitivity and power consumption It draws only 0 35 mA and measures accelerations in the range of 3 g Table 2 shows the decision matrix which summarizes why the ADXL330 was chosen Table 2 Accelerometer Decision Matrix IMMA7260Q ADXL330 m cane 2 2 3 Oor 3 2 2 7 GPS Device A GPS device is necessary to record the location of each impact Itis also responsible for setting the real time clock of the device The best GPS device for this project is one which has low power consumption low cost small size sufficient gain to obtain satellite fixes through walls and is simple to interface with a microcontroller The stand alone GPS device contains all necessary hardware to receive and process satellite signals to GPS coordinates This information is outputted through a UART interface The advantage of this setup is that there is no extra programming needed to calculate GPS coordinates The disadvantages of this setup are its cost and power consumption Most stand alone GPS devices cost greater than 50 dollars The power consumption is also relatively high since it includes its own processor to determine coordinates
32. worked per quarter were based on the tasks that were scheduled in the Gantt chart The breakdown of the labor budget is shown in Table 4 The labor cost for this project is 28 875 Table 2 Development Budget Product Quantity Price Per Unit Total Price PDA 1 400 400 GPS 3 65 195 Accelerometer 3 35 105 Battery 2 10 20 Case 1 5 5 PIC Development Kit 1 230 230 PIC24FJ64GA002 10 2 20 Memory Card 3 10 30 Memory Card Socket 2 4 8 Analog Components 50 Total 1063 Table 3 Device Budget Product Price GPS 65 Accelerometer 35 Battery 10 Memory Card 10 Misc and Analog Components 12 Case 5 PIC 2 Memory Card Socket 4 Total 143 Table 4 Labor Costs Quarter Hours Cost Summer 25 875 Fall 150 5 250 Winter 350 12 250 Spring 300 10 500 Total 595 28 875 LEGGEL oBeg Constraints In preparation for the design of the device certain real world constraints needed to be acknowledged These constraints guided the design process by providing a general basis on which to make specific design decisions Economic Economic considerations include the cost of staffing hours the cost of devices and the cost of miscellaneous development equipment In order to minimize the cost of labor the design of the device was made as simple as possible The number of components was kept low to reduce

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