Thursday, December 12, 2019

Portable Manual Cell Phone Charger free essay sample

This Undergraduate Thesis entitled â€Å"PORTABLE MANUAL CELL PHONE CHARGER† prepared and submitted by CARL NICKO ARDIENTE, KEVIN CASTRO, MARIA LUISA LEONARDO, PATRICK LANCE LOSARIA, CATHLEEN MARIE MASCARINAS, ALGIE JEFFERSON OLMILLA, JOSE ANTHONY PERALES, ALYANNA MAY ROBLE and ARGEO TORING in partial fulfillment of the requirements for the degree of BACHELOR OF SCIENCE IN ELECTRONICS ENGINEERING has been examined and is recommended for acceptance and approval for ORAL EXAMINATION. THESIS COMMITTEE After a few days, telecommunication companies would have already repaired their towers in some areas. By then, residents’ phones would have run out of battery power. Advancements in cellphone technology have also caused negative effects on cellphone battery life. The amount of power required to use the cellphones has increased due to the increase of features cellphones have been given. However, the size of the battery has either stayed the same or gone smaller. This causes battery life to significantly decrease as the technology increases. With this problem at hand, an alternate method of acquiring energy must be used. Of all methods, generation of electrical energy from mechanical energy has proven itself efficient. With this, human effort will be widely used to charge cell phones. Taking into consideration the situation of our fellow brothers and sisters suffering from the aftermath of typhoon Yolanda last November, the researchers urged to find an alternative solution to enable manual charging of cellphones. This study aims to design a portable manual cell phone charger that will answer the needs of the citizens be it typhoon victims or citizens who are incapable of using electrical outlets to charge their cellphones. The reason for a portable manual charger is to allow people to easily carry these around and manually charge their phones anytime and anywhere. Related Literature All electronic devices need power in order to work. Some electronic devices utilize power directly from the main 220volts line, while others use batteries in order to run. Portable devices such as flashlights, small radios, and phones use batteries in operating. These portable devices are very much useful especially when a catastrophe or emergency happens. Some of these portable devices, specifically the cellphone, uses rechargeable batteries. Though a battery can offer power, the power is limited. And so various ways of recharging cellphone batteries, or just batteries in general, have been explored. For instance, Jen Hao Dai (2010) invented a hand crank generator that can produce electrical current using various mechanical parts, gears, and a generator. The crank was set to be manually operated to drive the gear transmission which then makes the clutch gear move and make the generator revolve which produces electrical current. When the manual cranking of a user stops, the clutch disengages from the motor gear, and then the weighted wheel makes the generator to revolve a little more due to the presence of inertia, producing a little bit more power for the device connected with it. Though this system makes a user exert a little less effort in operating the crank generator with the help of the weighted wheel, this device can only charge a single particular electronic device at a specific time with no indicators when a device is already fully charged, which then wastes a user’s time and effort in cranking after the device is already full with power. In another study by Po-Jung Hsu (2005), a portable solar powered battery charger that can charge a phone through using the sun’s solar energy or an internal rechargeable battery built inside the device was implemented. Hsu’s invention took advantage of the abundant radiant energy from the sun. This energy can be stored directly to the cellular phone or to the internal battery of this portable device. The energy stored in the internal battery of this device can also be used to power or charge the phone when there is no more solar energy that can be harvested. The use of solar energy in order to charge a cellular phone can be very advantageous, since it is almost everywhere and it is a renewable source of energy. However, the problem appears when the need for energy arises during night time or on places where there is no sun light whatsoever or when the user forgets to charge his or her battery during day time. A study of Weston L. Moyers et all (2010), shows the promise of a hand-crank generators in producing power without the need for electricity. Though the power that it can produce is not that much and solely depends on the one using it, but it is very efficient and ideal that even militaries are using these during mission deployments. The design utilized a samarium cobalt magnet alternator nested in a harmonic drive which is capable of producing three phase AC voltage which will then rectified and filtered. It also offers a voltage regulator as precaution in case the generator is cranked too fast that it produces a greater unregulated voltage that could potentially damage electronic equipment. With further test with the generator, it was found out that its peak efficiency is 62% and could be achieved by rotating the crank by 95 rpm having an output of 73 watts. This is more than enough to power up a smartphone that badly needed to be recharged. Another study of Long Wu et all (2007) offers a 50 W output generator. The design is also very portable and has a limited mass which makes it ideal for people travelling to isolated areas. The study of Arjen Jansen, Peter Slob (2003) on the other hand features a much more complicated mechanical structure within the system in order for a comfortable one-hand cracking in which the user will not exert too much effort to power up the system. Their research also includes experimental set-up of 8 subjects using the hand crank generators, measuring their maximum power output and the time of exhaustion at different power levels. The results are analyzed and showed a sustained power output of 54  ± 14 W. Dan Dai and Jing Liu (August 2012) created a new wireless charger named as Human-power wireless charger (HPWC). It can harvest human energy, convert it into electricity, and then deliver to mobile electronics wirelessly. Unfortunately, their test results indicate that its output voltage approximately around 400mV is still not enough to be used by the consumers. A wireless charger indicates a boost in the technology thus, it can still be used as a basis for the development of future electronic gadgets. Another study made by Daniel Harrist determines if it is possible to capture enough power in a cellular phone in order to charge the battery. The requirements for the system Harrist presented are that it can be incorporated into a base station and the operating frequency is set. The design of the board and choice of antenna for the stand are the focal point of the experiments Harrist performed. Power needs to be supplied to the energy harvesting circuit by an external transmitter. This transmitter will send a signal at the set frequency. The test system will then receive this signal through the energy harvesting circuit. This circuit will convert the received signal into DC voltage to charge the battery. Though this system was successful in charging the battery, some issues still remain like the antenna used in the stand was about half as efficient, from a voltage standpoint, as the off-the-shelf quarter-wave whip antenna used in earlier tests made by Harrist. There needs to be much more emphasis on the antenna design in order to get the power transfer to a sufficiently high level, specifically, to the level of the quarter wave whip antenna. Manufacturers designed various types of mobile phone chargers described by eBay (2013) to fit different needs and lifestyle requirements. The first type is the wall charger, which can be described as the typical charger having a cable connected to the phone and a plug to the outlet. This type of charger is widely used in urban areas and areas where abundant electricity is supplied by a source. Basic charger circuit designs can be taken from this type. For his invention of a portable USB-mini charger, a patent has been given to David Khalepari (2011). This invention allows for a number if possible input sources. These include male connectors for a 12V cigarette lighter as well as a 120V AC outlet. A current inverter is also attached to convert any possible AC input into DC. These DC inputs are then regulated to meet USB standards. Lastly, a multi-hub USB adapter is attached with different ports to accommodate the different number of USB connectors. Because the device is intended to be small, it is certainly portable. However, it depends on available wall sockets or external supplies. The second type is the car charger, which uses either an auxiliary plug or the cigarette lighter outlet of cars. This type takes electricity directly from the car’s battery. Car chargers are further subdivided to four: universal, fast and trickle chargers (eBay, 2013, para. 6). This can only be used by people who own vehicles though. The third type, emergency charger, is for people who are regularly away from place to place. This type can be powered by double A or triple A batteries, and cannot charge a phone strongly compared to the other types but enough to allow users a 1-hour phone call or so, in case of emergencies (eBay, 2013, para. 10). A patent was given to Fu-I Yang (2006) for his invention of a portable power supply. This power supply makes use of Lithium batteries to supply USB powered devices. The invention makes use of a DC-to-DC voltage booster circuit to increase the voltage to the 5V DC that is of the USB standard. It also contains USB sockets in which the devices are to be plugged into. All of this is enclosed in a slender casing. Because his invention makes use of batteries as a power source, it has the capability to become portable. However, if appropriate batteries cannot be found, the portable charger cannot be used as well. Our project would like to avoid using batteries as these may not be available in times of emergencies. Deborah Hall (2010) also filed a patent for an electronic device back-up charger. The patent claims to be an electric device back-up charger comprising of housing with electrical connectors, compartment for battery storage, a conventional battery regulator circuit, and a female connector to serve as connection to the electronic device. It makes use of standard AAA sized batteries as an input source for the charger. Similar to the invention of Yang however, this charger is dependent on the availability of the battery itself. Another device is the Prototype Mechanical Charger by Denise Nadine Caranto (February 2011). In this project, she used a commercially available AA battery as the battery to be charged. She inputted a mechanical battery and let it pass to some circuitry in order to convert it to an electrical battery. She measures the output power and it efficiency, and concluded that there were no significant difference in electrical charger and mechanical ones, thus making the project a success. The last is the green charger type. Manual, mechanical, solar-powered, wind-powered chargers and the like all belong to this type of chargers. Portability of this type may vary. Some can be attached to bicycles and pedaling generates the electricity to charge up the phone (Howdy, 2011). Some designs existing outside the country make use of hand cranks to turn a dynamo. Most of all, this type can be used by anyone anywhere in the world, depending on the user’s choice. Bland (2009) and Howdy (2010) presented their respective procedures in creating a pedal-powered phone charger. A mini generator is mounted near the wheel and is connected to the circuit consisting majorly of the rectifier, capacitor and a regulator (Bland, 2009, para. 3). The circuit can be placed in the handlebar for protection and user’s convenience (Howdy, 2010, para. 7). Basically, the same principle can be applied to a hand crank generator; the only difference is that a person will have to use his hand to turn the motor instead of pedaling a bicycle. Though the pedal-powered phone charger has its advantages, certain disadvantages were also posted as, â€Å"The generator made riding significantly more difficult due to the friction of the roller against the tire, so you might want to disengage the generator on hard uphill climbs. Also, a lot of potential energy is wasted on long downhill runs, since voltage over and above 5V is lost as heat from the regulator† (Bland, 2009, para. 12). Certain additions or changes will have to be made to the circuit to address unforeseen concerns, at the same time improving the quality of the charger. A research study of L. I. Anatychuk et al. (2011) features a self-contained thermoelectric generator for cell phones. Their research and development of a 1 W thermoelectric generator for cell phones is a physical model that contains cylinder-shaped catalytic heat source that processes a catalytic combustion of gas fuel. A computer simulation method was then used to determine optimal parameters of the thermopile, catalytic heat source, and microgenerator heat rejection system whereby the efficiency of gas combustion heat conversion into electrical energy was a factor of two higher compared with existing analogs. Their generator design is described, and results of their experimental research on its parameters and the charging rate of cell phone batteries with capacity of 900 mA h to 1600 mA h were given. Its operation time is also 8 hours to 10 hours before it can be refueled back. In the self-contained operating mode of various low-power devices, the elaborated thermoelectric generator with a catalytic heat source can be an alternative to traditional sources of chemical energy. However, full charging of the cell phone battery would last to a minimum of 4 hours. Another study by Ming Zhen Liao (2002), a built-in hand operatable generator for a cellular phone was designed. It contains a rechargeable battery, a charging circuit, and a hand turning generator with an operating shaft. This generator can either be a DC or an AC dynamo equipped using the hand turning wheel or the hand operated crank emerged out of the cellular phone housing. The generator supplies the power to a charging circuit by rotating the wheel or the crank with hand so as to replenish electricity into the rechargeable dry battery of the phone in time of need at any place so as to keep the phone in a constant workable condition. The power generating means is handy, compact, and able to be installed in a limited accommodation space in a conventionally constructed cellular phone. The built-in generator of this invention can keep the phone power source always in a reliable state to make the communication without the fear of unexpected interruption. However, since it is mechanically driven, you cannot simultaneously use the cell phone while manually charging it. Given enough time, the twisting and turning of the hand turning wheel can also cause weariness towards your fingers. THE PROBLEM Statement of the Problem This study aimed to develop a portable cellphone charger that would allow mobile devices to remain powered 24 hours a day and 7 days a week. In particular, this study aimed to answer the following questions: 1. What is the effectiveness of different charging mechanisms? a) Hand-cranked b) Solar power c) Battery d) AC line e) Wind f) Pump 2. What circuit design would allow the greatest efficiency in charging mobile phones? 3. How often do mobile phone users need to charge their phones? 4. Will manual charging tire its users before getting sufficient amount of charge to the phone? Significance of the Study This study would be beneficial to the following: The cellphone users who frequently travel. This will allow them to continue charging their phones without the need for electrical outlets; The cellphone users who are victims of natural calamities such as earthquakes and typhoons that they be independent from conventional sources of electricity and continue to use their cellphones even when power lines are down; The companies developing electrical gadgets that this may allow companies to save more in production costs for mass production. Also, improved circuit designs will mean that the gadgets themselves will be of better quality and more competitive to others. RESEARCH METHODOLOGY This study used the quantitative and qualitative style of research. Through giving out questionnaires a quantitative style of research was implemented in order to gather relevant data from the selected population. The research will focus on acquiring data pertaining to the efficient and convenient cell phone charging method, construction, and user utilization. This is backed up through analysis from personal interviews with experts from different concerned fields and be able to do a more in depth research with their suggestions. From our gathered information, the researchers will confirm the effectiveness of a considerably small mechanical cell phone charger that can also store energy. Research Environment The University of San Carlos was the locale of the study. The University of San Carlos has two elementary and two high school departments, eight colleges and a graduate school. There are four campuses, three of which are for tertiary students the Main Campus which is located in P. del Rosario St. , the South Grade Campus in Private, the Talamban Campus in Nasipit, Talamban and North Campus in Mango Avenue. The Talamban Campus houses 4 colleges of the university. The Bunzel building, which is considered as one of the oldest building in the campus, houses the college of engineering and some from the college of arts and sciences. The college of engineering has 6 departments. The EE/ECE department was considered to be the biggest in the college of engineering having more than 1,000 students. The 5th year students from this department are perceived to be generally more knowledgeable in electronics than the lower years. Research Participants Since our targeted source of data were the students under the EE/ECE Department, the participants for the survey were taken from 5th year Electronics Engineering students of the University of San Carlos during the second semester of the Academic Year 2013-2014. A total of fifty (50) participants were considered for the survey. These students have their own personal cell phones and frequently use their cell phones. Research Instrument Questionnaires were used by the researchers as the instruments of the study. These questionnaires were given to 50 corresponding participants. The respondents were asked questions regarding the design and effectiveness of the proposed device. This will gauge whether future users will find it effective and efficient or not. The researchers also included questions regarding marketability and predictability of whether or not the device will be a necessity in the near future. Other than questionnaires, interviews were done to facilitate a good standing for the research. The Electronics department faculty was asked if they could help in the facilitation and decision making as to which design was the most suitable that would meet the purpose of the research as well as its future users. Research Procedures Gathering of Data. The study used the convenience procedure of sampling. Selected 50 students were asked to answer the survey questionnaires. The questions were related to their use of mobile phones and the corresponding chargers. There were also questions wherein the respondents were asked to analyze given situations regarding mobile phone chargers. Some questions inquired about the respondents personal preferences and choices. ECE faculty members were scheduled for an interview. They were interviewed regarding circuit designs of mobile phone chargers. Some questions were answerable by their deeper knowledge and expertise on circuitries related to mobile phone chargers, while some were also answerable by their choices and preferences too. The researchers waited for each survey respondents to finish answering the questionnaire before leaving. This was done to have an efficient data gathering. Answers from the survey and interview contained the respondents personal responses, ideas, opinions, views and comments. Thus, the researchers made sure to keep them within ourselves and that the respondents were given the option to either write their names on the questionnaires or not. Treatment of Data. The data gathered from the 50 participants and the ECE faculty interviewees were recorded in response to the first problem regarding the effectiveness of the different charging mechanisms. In addition, to interpret the data gathered, the researchers sorted each questions by tallying. A table was used to tally the data. The table included the number of surveyed participants, the type of question whether Yes-No questions, WH questions and multiple choice questions. The table also indicated the frequency of the surveyed participants’ answers corresponding to each choice, and the percentage of their answers to the over-all data. Another problem concerning the proposed device’s marketability and necessity were also recorded and tallied in tabular form where frequency and percent would also be shown. DEFINITION OF TERMS The following terms are defined as used in the study: Manual refers to a work done by hand and/or other physical part of a human body. Convenient. Easy to handle; easy to do/perform; comfortable to dealt with. Utilization. Making use of what is available; nothing is wasted, all is used. Portable refers to an object which can be easily carried or moved around from one place to another. Telecommunications refers to the way of communications of two distant objects. Mobile device refers to an electronic device which can be easily brought. Cellphone. A mobile device used for communication. Cellphone charger. An electronic device used to charge a cellphone Electronic device. A device which is constructed electronically. Electronics. A technology concerned with circuit designing and understanding the behavior of electrons. CHAPTER 2 TABULAR PRESENTATION OF DATA, ANALYSIS AND INTERPRETATION This chapter constitutes the presentation, analysis, and interpretation of the data gathered during the conducted survey in finding out the efficient and convenient cell phone charging method, construction, and user utilization. The quantitative data came from the 50 distributed survey questions completed by fifth year ECE students of the University of San Carlos while the qualitative data came from the interviews done to a few ECE faculties. A tabular form of data for the survey is presented, displaying frequency counts, and percentages. While individual answer from each interview question is interpreted. Survey Questionnaire The tables presented displaying frequency counts and percentages are gathered by the researchers and show the following results of the survey that have been yielded from the respondents. Table 1. Frequencies of Cell Phone Usage N=50 Response F % Never 0 0. 00 Seldom 2 4. 00 Just when people text and call 21 42. 00 Frequent 12 24. 00 Always 15 30. 00 Total 50 100. 00 Table 1 shows that 21 (42%) respondents from the selected population use their cell phones only when they receive text messages and calls. It is also interesting to note that 15 (30%) of the respondents claim to use their cell phone always. This is because most of the respondents are very busy students that they only use their cell phones for communication. Since the respondents are graduating students, it is expected that they are tending to a lot of things like thesis for example. Table 2. Common Uses of Cell Phone N=50 Cell Phone Uses F % Calling 30 60. 00 Messaging 50 100. 00 Internet surfing 15 30. 00 Playing games 21 42. 00 Social networking 15 30. 00 Others: Listening to music 1 2. 00 Alarm 3 6. 00 Reading 1 2. 00 Notes 1 2. 00 Table 2 reveals that among the various feature of a cell phone, messaging service is widely used by all of the respondents (100%). The table also reveals that cell phone is also mainly used for calling purposes, although not as much as its messaging service. The reason for this is that messaging is the most efficient method of communication because of its low cost compared to the other methods on using the cell phone. Text messages can also be read at the receivers’ convenience. Table 3. Length of Battery Life N=50 Response F % Less than 12 hours 12

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