Case Study (Teacher’s Guide) – The Technology behind Game Console Case Study (Teacher’s Guide) – The Technology behind Game Console Case Study: The Technology behind Game Console (Teacher’s Guide) Case Study (Teacher’s Guide) – The Technology behind Game Console Author Mr Chiu Yat-ming, Michael Lecturer, Department of Electronic & Information Engineering HK Institute of Vocational Education (Shatin) Project Coordinators Mr Li Yat-chuen Senior Training Consultant Institute of Professional Education And Knowledge, VTC Mr Tsang Siu-wah, Ephraim Training Consultant Institute of Professional Education And Knowledge, VTC The copyright of the materials in this Case Study belongs to the Education Bureau of the Government of the Hong Kong Special Administrative Region. Duplication of materials in this Case Study may be used freely for non-profit making educational purposes only. In all cases, proper acknowledgements should be made. Otherwise, all rights are reserved, and no part of these materials may be reproduced, stored in a retrieval system or transmitted in any form or by any means without the prior permission of the Education Bureau of the Government of the Hong Kong Special Administrative Region. © Copyright 2010 Note by the Institute of Professional Education And Knowledge, VTC: Every effort has been made to trace the copyright for the photographs and images in this Case Study as needed. We apologize for any accidental infringement and shall be pleased to come to a suitable arrangement with the rightful owner if such accidental infringement occurs. 4 Case Study (Teacher’s Guide) – The Technology behind Game Console Case Study: The Technology behind Game Console (Teacher’s Guide) General Information Subject: Design and Applied Technology Level: S4-6 Learning elements: Knowledge Contexts Process Strand 3 Value and Impact Values in technology and design Historical and cultural influences Entrepreneurship and enterprise Module 4 Electronics Evolution of electronics in modern society To compare the working principle of a game console with a computer through the study of their construction To understand the design consideration of a product through the study of technology in a motion sensing game controller To understand users’ impacts created by motion sensing game controller through study and discussion Small group discussions and presentation Impact Analyse and evaluate manufactured products Understand the impact of new technologies on the quality of life Manage a product design project State the impact of emerging and converging electronic products in society Case Study: Students should be made aware of the relevance of the technology they are studying to the real world. Case studies on technology and design enable students to put their learning into an authentic context, and so provide an additional resource that can add a new dimension to learning about technology and design. Authentic context: Topics Covered: Compulsory Part Elective Part Through the study of motion sensing game controller development, students could explore the development process and social impacts of an advanced technology product Strand 3 : Value and Impact Module 4 : Electronics 5 Case Study (Teacher’s Guide) – The Technology behind Game Console 1. Teaching Notes 1.1 Basic Components of a Game Console A game console can be considered as a specially designed computer for game playing. Its main components are similar to a computer and have more or less the same functions. The main components of a game console are listed below: CPU Memory Operating system Game Controller Video output Audio output From the list, you could find that a game console has CPU, memory and operating system. Same as the case in computer, an operating system of a game console is a set of software interfacing between its application software, which is a video game, and its hardware. The function of an operating system is to simplify the job of writing application program (i.e. video game) to run on the game console so that the programmers could save their effort in developing program to directly control its hardware. A game controller allows game player to interact with the video game e.g. control onscreen object and input information. Early game controllers are simple paddles or joysticks. Nowadays, most game consoles come with sophisticated game controllers. All game consoles provide an output signal for display on TV. In most consoles, dedicated graphics processor is used to process their graphic to high quality and then generate its TV output signal. In addition to a dedicated graphic processor, some game console has another dedicated integrated circuit to handle the audio processing and outputs sound. 6 Case Study (Teacher’s Guide) – The Technology behind Game Console 1.2 Game Controller Similar to the concept of a computer, a game controller is an input device of a game console. It can be used to control the movement or actions of objects in a video game. Typically, game controller is used to control the player character’s actions and movements but the exact types of object controlled with game controller actually vary from video game to video game. A game controller may simply a keyboard, mouse, gamepad, joystick, paddle or any other device for receiving input. Some devices, such as keyboards and mice, are actually generic input devices and are not strictly limited to use as game controller. On the other hands, there are specially designed game controllers to suit the kinds of game object movement or action in certain types of games / game console. Examples include steering wheels for driving games and light guns for shooting games. 1.2.1 Joystick Technologies Joystick is a traditional game controller. It was designed to translate the movements of a plastic stick into electronic signals. In the simplest joystick design, the movements of plastic stick were translated into close or open of electrical switches and then the computer sense the absence or presence of current through these switches. By this mean, digital information of “1” and “0” can be transferred from player to computer. [Note: here, we can link to the concept covered in Chapter 1 Electronic Signal, Device and Circuit and Chapter 3, section 3.3.6 Simple Interfacing.] Joystick allows game player to control game like Pac Man or Tetris. However, when it comes to games required game player to do more complicated actions like controlling an airplane in fight simulator. For this purpose, the design of joystick was enhanced later so that they become able to monitor the movements along x-axis (left to right) and the y-axis (up and down) by using two potentiometers, one for x-axis while the other for the y-axis. For further information, please refer to [1] in the reference under section 4. 7 Case Study (Teacher’s Guide) – The Technology behind Game Console 1.2.2 Motion Sensing Game Controller Although it is possible to design video games that have its game player using a joystick to do complicated control actions such as controlling an airplane to do sharp turns, barrel rolls and loops. However, the plastic stick and button in joystick are not used in the same way as an airplane steering wheel (called york). As a result, it is necessary for game player to learn how to make use a joystick in the way assumed by the game designer. Motion sensing game controller is advancement in the history of gaming interaction as compared to traditional input devices such as joystick. It represents another step on the road to total immersion in game playing. Its objective is to provide game player with an intuitive input device that it is easier to pick up how to use it. More specifically, it allows the design of video game in which player is only required to move the game controller as if they were moving the real stuff. For example, it allows design flight simulator game in which player can control an airplane by simply moving the game controller in the way you want the airplane to move and then airplane will move on the screen accordingly or table tennis game in which player can swing a motion sensing game controller like a table tennis racket. More rigorous studies of motion sensing game controller versus joystick can be found in [2, 3, 4]. Motion sensing game controller typically contains accelerometers and gyroscopes (for some game controller only) to sense the movements of the game controller, which is typically held and moved with hand by a game player. Beside held and moved with hand, Wii remote can be attached in many input peripherals boxing gloves, Wii Helm, sport pack, fishing reel, steering wheel, zapper and Nunchuk. Ideally, a motion sensing game controller should be able to sense the following six types of movements: Rotation about the x axis, i.e. rotate up and down (called roll) Rotation about the y axis (called pitch) Rotation about the z axis i.e. rotate left and right (called yaw) Left and right movement (along +x axis and –x axis) Back and forth movement relative to the TV screen (along +y axis and –y axis) Up and down movement (along +z axis and –z axis) +z TV Screen Motion Sensing Game controller +x +y 8 Case Study (Teacher’s Guide) – The Technology behind Game Console 1.3 Accelerometer and Gyroscope Accelerometer and gyroscope are two types of motion sensors that motion sensing game controller incorporated with. An accelerometer is an electromechanical device for measuring acceleration due to moving or vibrating the accelerometer. More specifically, an accelerometer measures linear acceleration that it experiences relative to free fall. That is, its acceleration relative to a fixed reference frame minus the acceleration due to gravity. As a result, when an accelerometer is at rest on the Earth’s surface, it will indicate a 1g upward along the vertical axis (z axis). To obtain the actual acceleration (due to motion only), we subtract 1g from the accelerometer output. On the other hand, when the accelerometer is at free fall, its output will be zero. To better appreciate why accelerometer measures as such, we may consider what a person feels on his back (due to his seat) when he sit inside a vehicle accelerating forward or slowing down. Accelerometers can be used to measure vibration on vehicles, machines, buildings, process control systems and safety installations. They can also be used to measure seismic activity, inclination, machine vibration, dynamic distance and speed with or without the influence of gravity. For further details on the underlying principles of accelerometer, please refer to [5,6,7,8]. A gyroscope measures angular velocity around a particular axis (Note: accelerometer measures acceleration and gyroscope measure velocity). By using the original orientation as the initial condition and integrating the angular velocity, the current angular orientation is known at all times. For further details on the underlying principles of gyroscope, please refer to [9]. We usually find gyroscopes in GPS and Car stability control systems. Both accelerometer and gyroscope require the use of integration to determine current position. However, the calculated results of position suffer from "integration drift”. More specifically, small errors in the measurement of acceleration and angular velocity are integrated into progressively larger errors in velocity, which is compounded into still greater errors in position. Since the new position is calculated from the previous calculated position and the measured acceleration and angular velocity, these errors are cumulative and increase at a rate roughly proportional to the time since the initial position was input. Therefore the position must be corrected periodically. 9 Case Study (Teacher’s Guide) – The Technology behind Game Console 1.4 Wii Remote Wii Remote, nickname is Wiimote, is a motion sensing game controller that represents a recent innovation in game controller. It was introduced in Nintendo’s Wii game console. Its major success is in giving the game console the ability to sense three dimensional movements of itself. In each Wii remote, it uses three key technologies, namley accelerometer, PixArt image sensor and bluetooth. Following subsections provide a brief summary on these key technologies. For further details on how Wii remote works, please refer to The Wii Remote and You http://people.cs.vt.edu/~bowman/3dui.org/course_notes/chi2009/wiimote.pdf Sensor Bar highlighting IR LEDs http://bbs.wiichina.com/simple/index.php?t6127.html The Wii Remote is able to sense acceleration along three axes using its accelerometers and determine where it is pointing. The Wii Remote uses two AA batteries, which can power a Wii Remote for 60 hours using only the accelerometer functionality and 25 hours using both accelerometer and pointer functionality. 1.4.1 Accelerometer Each Wii remote has an ADXL330 3-axis accelerometers (designed and manufactured by a company called STMicroelectronics, who was originated from Taiwan [10]), which is able to determine the movement along x, y or z axis and measure up to three times the force of gravity by sensing small voltage changes that output from the accelerometer during movement in each of the three axis. As its accelerometer always sensing gravity, when the Wii remote is completely stationary (i.e., at rest), it will show an acceleration of 1g in the upward direction (i.e., +z direction). If someone drops the Wii remote and let it freefall, it will report zero acceleration. If Wii remote is not moving, it is not possible to calculate yaw (see next subsection for how the sensor bar and the image sensor can determine yaw). However, when Wii remote is at rest, it can calculate the roll and the pitch of itself using the following equations: roll = arctan2(az,ax) pitch = arctan2(az,ay) where ax, ay and az are the acceleration along the x, y or z axis respectively. 10 Case Study (Teacher’s Guide) – The Technology behind Game Console arctan2(y,x) uses arctan|y/x| to determine the angle and use the signs of both x and y to determine which quadrant the angle should be in. When the Wii remote is moving, the mathematics gets more complicated (see www.wiili.org/motion_analysis for details). 1.4.2 Image sensor The Wii remote can be used as a pointing device e.g. to point at menu options or objects e.g. enemies in a first person shooter game. For this purpose, the Wii Remote features a PixArt image sensor, allowing it to determine Wii Remote’s roll and yaw, and hence determine where it is pointing at. (PixArt is a Taiwan company. It specializes in CMOS image sensors and related IC design such as image-processing algorithm IC design. See http://www.pixart.com.tw/ for more about it.) The PixArt image sensor is an Infrared camera situated at the front end of the Wiimote. The camera has a resolution of more than 750,000 pixels (In digital imaging, a pixel or picture element is the smallest item of information in an image. Pixels are normally arranged in a 2-dimensional array/grid). The camera is connected to an image analysis chip that has facility to identify up to four individual Infrared light sources and report position, approximate size and level of intensity. Unlike a light gun that senses light from a television screen, the image sensor senses light from a sensor bar, which can be used with a television of any type or size. The sensor bar is about 20 cm (8 in) long and features with two clusters of 5 infrared LEDs. The LEDs farthest away from the center are pointed slightly away from the center, the LEDs closest to the center are pointed slightly inwards, while the rest are pointed forward. This spread helps to improve the image sensor’s range. Sensor Bar The sensor bar can be placed above or below a television, and should be centered. If placed above, the sensor should be in line with the front of the television, and if placed below, should be in line with the front of the surface the television is placed on. When the Wii remote is pointed at the sensor bar, the light emitted from each cluster of LEDs is focused onto the image sensor as two bright dots. Considering the sensor bar forms the base of a triangle (with length l) and the Wii remote at the opposite corner of the triangle, 11 Case Study (Teacher’s Guide) – The Technology behind Game Console using a principle called triangulation [11], it is possible for Wii remote to calculate the distance (d) between the Wii remote and the sensor bar. In addition, rotation of the Wii remote can also be calculated from the relative angles (,) of the two dots of light on the LED array. This allows the Wii remote to act as a pointing device at a distance up to 5 meters (approx. 16 ft) away from the sensor bar. l d It is not necessary to point directly (or orthogonally) at the sensor bar but the above calculation works best when the Wii remote is really pointing directly at the sensor bar since the image sensor cannot tell that the distance between the two LEDs it sees from the sensor bar is due to the Wii remote is rotated or not. This represents one of many ambiguities with the Wii remote. One other issue with the Wii remote’s image sensor is that it will pick up any infrared light in the room (e.g. incandescent light bulbs or candles), which can cause accuracy problems. 1.4.3 Bluetooth By using Bluetooth technology, action data collected from the sensors (e.g. image sensor) is sent back to the game console as far as 10m away (due to the limitation of Bluetooth). As a pointing device, the controller can send a signal from as far as 15 feet away (due to the limitation of the image sensor). Up to four Wii remote can be simultaneously connected to the same game console for playing multiplayer game. 12 Case Study (Teacher’s Guide) – The Technology behind Game Console 1.4.4 Limitations in Motion Sensing Game Controller Besides the limitations mentioned in the subsection 1.4.1 Accelerometer and 1.4.2 Image Sensor, the Wii remote also have the following problems [12]: (a) 1:1 Control When we use the Wii remote to control the on-screen game object, it is often for me to expect the “in game” character to do exactly the same movement as the game player does. For example, when we swing our arm, we want to see the in game character do the exact same movement with their sword. This is what some people call 1:1 control. If this can be achieved, the game player will fell more immersive. But, this is far easier said than does. As accelerometer is designed to measure the sum of linear and centripetal acceleration, gravity and vibration, extracting the motion along individual axis from the accelerometer’s linear motion information is not feasible. As a result, it would confuse the linear motion of the game controller with that due to centripetal acceleration. If game player make subtle hand movements such as the player swing the baseball bat in Wii Sports, Wii remote will not be able to produce an 1:1 representation of player hand motion in screen. Furthermore, the Wii remote has also difficulty to differentiate small motions from big motions. As a result, the remote is not able to track where it is in the 3D space. In game like tennis playing, the Wii remote are often left the player wondering why their character did, or did not, swing the racket in response to the player’s swing. The Wii MotionPlus is a small controller add-on for attaching to the Wii remote. It has an InvenSense IDG-600 dual-axis MEMS (Micro-Electro-Mechanical Systems, which is a technology enable to fabricate in silicon as a chip and hence allow for cost and size to reduced that the gyroscope become suitable for consumer electronics.) gyroscope [13] to supplement the capabilities of the accelerometer and Sensor Bar in the Wii remote. But, the Wii MotionPlus make the Wii remote extends by approximately 4 cm in length. When combined with the other sensors and the Sensor Bar, the Wii MotionPlus suppose to give Wii remote the capability to sense all six types of movements that we mentioned in subsection 1.2.2. However, the technology isn't flawless, its hardware and software could still not able to smoothly achieve the true 1:1 representation capability. With Wii MotionPlus, the wiimote’s position and orientation are estimated by first integrating the accelerometer for velocity and then once more for position, and once for the gyro reading for orientation. Because the MEMS based accelerometer in the Wii remote and gyroscope in the WiiMotionPlus have very high drift rates that vary as a 13 Case Study (Teacher’s Guide) – The Technology behind Game Console function of temperature, they are only able to estimate WiiMote’s position and orientation for a matter of seconds before they loose all accuracy. They correct the position and orientation using the infrared camera’s observation of the Sensor Bar. Again, if the Wii remote is pointed away from the Sensor Bar (the field of view of the infrared camera is very limited), the estimation will start to degrade and drift off until the Sensor Bar is again observed, which will allow the Wii remote to again correct its estimation parameters. (b) Full Body Motion Wii remote was designed to estimate its own position in the 3D space but it is not able to sense the position of its game player’s entire body. It is because there are no sensors attached to other part of game player’s body such as the waist, elbow or head to detect these area’s movements. Furthermore, the image sensor in Wii remote is not able detect how far it is above the ground. For example, if on screen opponent attacks towards the face of a game player and the game player hold sword up to deflect the attack, but the game cannot interpret whether the controller is being held at eye level or the game player is defending his/her chest or torso. To solve this problem, a thumb stick (as in Wii Nunchuck) is used in combination with the Wii remote for a large amount of gestures and directional input to compensate for the lack of the capability to detect full body movement. But, this also makes the feeling of game playing not immersive. 1.4.5 6-Axis Motion Sensing Solution [14] In light of the discussion that we made so far, we still need a better way to solve the problem of sensing all the six types of movements that we mentioned in subsection 1.2.2. To the eye integrated circuit manufacturers, the way the WiiMotionPlus integrate an external gyroscope together with accelerometer in the Wii remote is again referred as a non-integrated solution. Following block diagram represents an integrated solution [14] offered by Ivensense. In the solution, a number of the company’s products are put together to solve the problem of 6 axis motion sensing. 14 Case Study (Teacher’s Guide) – The Technology behind Game Console IDG-650 X-axis Gyroscope ADC Dual-Axis Gyroscope Y-axis Gyroscope ADC 4x5x1.2mm IDG-650 Dual-Axis X-axis Accelerometer Output ADC 6-axis Output Z-axis Gyroscope Gyroscope Y-axis Accelerometer 4x5x1.2mm Z-axis Accelerometer IME-3000 3-Axis Accelerometer (3x3x0.9mm) InvenSense 6-Axis Motion Processing Solution Block Diagram (In the above diagram, ADC refers to Analog to Digital Converter) Further development in the technology of motion sensing game controller include integrating all the necessary parts as a single chip [15]. The locally manufactured motion sensing game controller quoted in the case study is of this type. A number of video about the game controller can be found from the Internet at the following links. http://www.youtube.com/watch?v=EC2DbggtbM8 (overview of the packing) http://www.youtube.com/watch?v=-0o8eqUTjbc (gaming example 1) http://www.youtube.com/watch?v=o8xViOhDdqU (gaming example 2) http://www.youtube.com/watch?v=ZV5Yw4Nd2xI (gaming example 3) http://www.youtube.com/watch?v=m6n71rnbAkQ (gaming example 4) 1.5 Importance of Game Technology [16,17,18] Game consoles are highly specialized computer that often required cutting-edge technologies for each of its main components including game processor, audio processor and CPU. Furthermore, it is very often these cutting-edge technology are invented firstly for playing video game (either for game consoles or PC used for playing game) before a number of them find their ways into other mainstream electronic products. For example, 3D video cards were called graphic accelerators, which was invented for playing game in PC and they are now found in every Personal Computer. Although the market for high-end game consoles may be small, the developments of these highly specialized cutting-edge technologies require the manufacturers to build an advanced 15 Case Study (Teacher’s Guide) – The Technology behind Game Console research-and-development laboratory. But, the developed technology, when used in their new game console, could help them to withstand the severe competition from other game console manufacturers. Hence, it is important for the game console manfuacturers to state in the art of the technology. Pedagogy In this case, the visual representation on game console and its accessories together with the cases will be more stimulating to the students than the textual basis. Video regarding the technology with game is available from the Internet [19, 20, 21,22,23,24,25,26]. Teachers can use the video as a stimulus to students with a more realistic local design situation in game console or its accessories such as Sengital (http://www.sengital.com). There are some tips recommended for the students to conduct group discussion: 1. Read the case materials at least twice and put down some footnotes or questions aside the paragraphs. 2. Jot down a list of the problems and issues that to be discussed. 3. Try to add meanings to the data presented in the case (if any) or any findings discovered during their research. 4. Try to apply the concepts and tools that they have learned earlier or in other subjects. 5. Be thorough in diagnosis of the situation and make at least one page summary of their group discussion. 6. Support any and all opinions among the group with well-reasoned argument skills and data until they can say “here our analysis show that …". 7. Use tables, charts, and graphs to present their findings or conclusion as far as they can. Sometimes simple summary tables or a bulleted paragraph will work wonders. 8. Prioritize their recommendations means make sure their practical recommendations are really practical; make sure they can be carried out in an acceptable time frame with the available skills and resources. 9. Review the recommended solutions to see if it really addresses all of the identified problems and issues, advices from other groups can be consulted. 10. Be conscientious to recommend some solutions or conclusions that could not have disastrous results if it doesn't work out as planned, remind them to be a responsible and conscientious case analyst and is tackling a real case. Teacher can take the role of a facilitator and recommend some worksheets in accordance with the case context. The worksheets can be some reflective questions so that they can be a formative assessment to determine how students are learning and to make sure they are 16 Case Study (Teacher’s Guide) – The Technology behind Game Console engaging in the learning process. The worksheets with appropriate designed tables and hints can help students to record their work systematically so that they can be easily monitored. This makes their learning outcomes become tangible and assessable. The follow-up activities recommended in this case study are the substantiation of contexts through different learning and teaching strategies e.g. Design Project, Visit. We believe that students can acquire the generic skills and explore the problem in a greater depth through this series of interactive activities. However, the classroom implementation is up to the teacher professional decision that is based on the teaching schedule and the learning outcomes depend on the readiness of students, lesson preparation and planning. 2. Schemes of Work The teaching scheme is served as a basis for teachers to plan for their own lessons. This topic is quite comprehensive and emerging. It involves the issues of different stage and design consideration. The primary planning just covers all the necessary tasks and experience that students might need to go through. Like any other case studies, students need to do a lot of background readings to formulate their own concept and understanding of the issue, otherwise they cannot play an active role in presenting their views in a provocative group discussion. This means students need to take many non-school hours to complete their tasks. Transforming knowledge and data from extensive information search and literature review into a comprehendible and presentable conclusion or practical recommendation is the acquisition of high-order thinking that involves integration of knowledge form different perspectives. Students may find it challenging in the beginning but they have to work on it. Students take time to familiarize with this students-centered learning activity instead of traditional “chalk and talk” ones. The role of teacher is like a coach to encourage them and set them an achievable goal for them to progress and success. We believe in the motto “Practice makes perfect”, once students are used to learn in this approach, and importantly, with the support of teachers, they will become a good case analyst. 17 Case Study (Teacher’s Guide) – The Technology behind Game Console No. of periods: 8 periods Duration of each period: 40 mins. x 2 Level: S5 or above Theme: The Technology behind Game Console Presentation: Powerpoint, video, game console and its accessories Period Teaching /Learning Activities 01 Introduction of Case Topic Teacher should explain the case study topic. It will cover different stages of forming a new product idea and introduction to game console Teacher needs to explain the assessment method and the expected learning outcomes with powerpoint presentation and worksheet Studying the case story Students need to understand the case as the background information; Self-assessing questions help them to identify the key issues; Class assignment in groups Encourage them to discuss the topic area in their group; Group carry on the problem identification works at home Forming groups and brainstorming Teacher divides students into small groups and encourages them to work in team. Grouping in according to their strengths and interest; Teacher can show a few minutes of Internet video to stimulate their interest to the topic Teacher asks the groups to discuss the problems found and summarize on the worksheet. Idea generation should start with brain storming among groups. Development 02 -03 04 05 -06 07-08 Presentation/project Meeting Students should final check and rehearse their presentation; Teacher explains the presentation / project meeting details Teacher gives timely feedback and correct answers if necessary. 18 Case Study (Teacher’s Guide) – The Technology behind Game Console 3. Assessment The checklist assessment rubrics are given to each student for their self-evaluation after each lesson. Teacher can discuss the checklist with them to perform formative assessment. Teacher should record the checklist results and monitor the students’ progress. The score rubrics are given to assess the final presentation by teacher and peers. The rubrics criteria can be subject to change by the teacher professional judgment. The benefit of using score rubrics is that students can know which areas they have performed well and which areas need improvement. Students should know the assessment criteria before working on the case so that they can divert their focus onto their learning. For a fair assessment, students can request to be assessed individually instead of as a group. They can state their percentage of contribution to the case before the assessment. Scores can be calculated in accordance to the contribution percentage and allocate to individual student. 4. Reference Materials / further reading materials [1] How Joysticks Work? http://www.howstuffworks.com/joystick.htm [2] Conventional Joystick vs. Wiimote for Holonomic Wheelchair Control http://www.springerlink.com/content/5383j64m7j56351q/ [3] Designing games for the Wiimote http://www.develop-online.net/features/58/Designing-games-for-the-Wiimote [4] Case study-the Nintendo Wii Remote http://nerdacumen.com/Case_Study_on_the_Nintendo_Wii_Remote_by_Matthew_Stringer.pdf [5] How does an accelerometer for Nintendo Wii work? http://wiki.answers.com/Q/How_does_an_accelerometer_for_Nintendo_Wii_work [6] Accelerometer http://en.wikipedia.org/wiki/Accelerometer [7] Accelerometers – build one yourself http://blog.dotphys.net/2009/07/accelerometers-and-build-one-yourself/ [8] What Do Accelerometers Measure? http://www.strapdownassociates.com/Accels%20Measure.pdf 19 Case Study (Teacher’s Guide) – The Technology behind Game Console [9] New iMEMS® Angular-Rate-Sensing Gyroscope http://www.analog.com/library/analogdialogue/archives/37-03/gyro.html [10] STMicroelectronics Drives Gaming Revolution with Nintendo's Wii http://www.st.com/stonline/stappl/cms/press/news/year2006/t2031.htm [11] Triangulation http://en.wikipedia.org/wiki/Triangulation [12] The Sad, Sad Truth of Sword Simulation http://www.vooks.net/story-11544.html [13] IDG-600 Integrated Dual-Axis Gyroscope http://www.invensense.com/products/idg_600.html [14] Ivensense introduces Single-Axis Yaw Gyroscope and 3-Axis Accelerometer to Complement Family of Dual-Axis MEMS Gyroscopes http://www.topas.de/presse1.html?&tx_ttnews%5Btt_news%5D=61&tx_ttnews%5BbackPid%5D =51 [15] 6-axis motion sensor http://www.semi.org/cms/groups/public/documents/web_content/ctr_032235.pdf [16] Video gamers drive high-end PC design http://www.cbc.ca/news/background/tech/videogames/fun-machine.html [17] How gamers drive the market http://icrontic.com/forum/showthread.php?p=585496 [18] Gamers Drive the Market http://backtalkandsass.com/Gamers-Drive-The-Market.pdf [19] Microsoft Flight Simulator with the Wiimote http://www.youtube.com/watch?v=_3hk2H-PhAo&feature=related [20] FlightGear Wii-mote Flying http://www.youtube.com/watch?v=KyFTc_XH0Zs&feature=related [21] Table Tennis - The Official Wii™ Version Video http://www.youtube.com/watch?v=oxxqx-evAdc [22] Wii ping pong http://www.youtube.com/watch?v=BI8xqTt1Ql4&feature=related [23] Flight simulator, Condor, Joystick, Cockpit http://www.youtube.com/watch?v=I52FUeAiIWA&feature=related [24] Flight Simulator Projected Screens http://www.youtube.com/watch?v=3szJjaX51ig&feature=channel [25] DIY Flight Simulator Multiple Monitors http://www.youtube.com/watch?v=iNoyHdWXUlI&feature=channel (part 1) http://www.youtube.com/watch?v=fkQKYlkgE6w&feature=fvw (part 2) [26] Moving Axis Flight Simulator http://www.youtube.com/watch?v=ECeLsCIxh3Y&feature=related (part 1) http://www.youtube.com/watch?v=RrC0_EFnLFE&feature=channel (part 2) 20 Case Study (Teacher’s Guide) – The Technology behind Game Console 21 Case Study – (Teacher’s Guide) Environmental Technology: Hydrogen-powered car 22