Sensors & Remote Electronic Control |
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Image courtesy of LANL. |
Electronic design, e-design, refers to a new form of composition that has emerged in the late twentieth century. This is the art and science of planning, designing and creating with electronic devices such as sensors, remote control devices and combinations which form a variety of robotic devices. The application of such technology is not yet common knowledge. "The impact of sensors will be as surprising in the decade ahead as microprocessors were in the 1980's and lasers were in the 1990's" (Saffo, 2002). However, as the science, math and social studies content areas in school curriculum put an emphasis on authentic data collection, educators will find ready application for such technology. Administrative uses will also become more significant in everything from heating and cooling to security.
The information such digital designs produce can in turn be integrated into web pages and positioned next to text that explains the information being reported. To better understand the role of sensors, a wide variety of uses need to be explored.
The first example is of a construction project that generated significant interest. In 2001, the Department of Transportation placed webcams (light sensor) near the site where a bridge, the U.S. 82 Greenville Bridge, was being built across the Mississippi River near Greenville, Arkansas. A pull down menu let viewers of the bridge project's web site switch between several other webcam views of the construction area during its construction and completion. The webcams have been removed since the completion of the bridge in 2006 but the web site has numerous pictures, some taken with the webcams, and a multitude of multimedia elements spawned by the construction project.
Totally unrelated to the bridge construction project, the USGS (United States Geological Survey) Department uses a variety of sensors to measure the flow of the Mississippi River. Where the webcam looked at the top of the river, there is another observation system with sensors under the water in the same location. The live incoming data is used to create a running graph of incoming data of water depth over an seven/eight day period. See http://waterdata.usgs.gov/nwis/uv/?site_no=07265455 and scroll down for the graphed data. Note the pull-down menus that lead to different ways to see the graph and other types of data reporting. For example, by selecting "Water Quality" from the pull-down menu, data from some 12 other sensors appears, including temperature, pH and nitrate counts. This data is not graphed, but through daily collection, could easily be entered into a spreadsheet and turned into different kinds of graphs for further analysis.
A second example is also a combination of webcams set up by one agency for one purpose and and sets of sensors set up by other agencies for different purposes. The challenge is to recognize and find some combinations. A live webcam of a lock 25 on the Mississippi River can be combined with USGS water data from a nearby point on the river, to gain a more comprehensive understanding of the river, its flood stages and the impact on people working and using the river area. These two separate scrollable web pages were also combined in a frameset pair to show both pages at the same time to facilitate comparing what is seen visually with what hidden sensors are reporting. The top frame can be scrolled to show a recent live image and the bottom frame to show real time sensor data and graphs.
A third
example is the massive and thorough sensor system set up in the James Reserve in California. This grid of observation devices includes a number of webcams of bird feeders and ground locations with many other kinds of sensors. Though this data is reported out at their web site, it has also been integrated with downloadable files for Google Earth that enable live data reporting while viewed from a three-dimensional map (see picture on right). It is important to scroll down this web page to find and download the Google Earth files, run them and explore this multimedia integration in the Google Earth application with their data reporting network. This is an excellent example of how digital systems can be used to support the fundamental role of observation in science and the value of mathematics in reaching higher levels of thinking and understanding.
Other sensor projects start out without any connection to the Internet and then with community help could expand to many other forms of live forms of data collection. The Mud Meter in Sylva, North Carolina does not report data to a web page but to a public sign readily visible to those driving by. Clicking the image will reveal the Tuckasegee Watershed web site and a clearer view of the sign. Making this same data available on a web page will greatly expand the number of possible observers. Adding a webcam to show the color of the river combined with USGS survey data from nearby data collection points would further extend the understanding of what is happening, especially during a rain event. Some sensor projections are not yet realized by massive in scale such as the Neptune Project that has been conceptualized for an under-water area off the coast of state of Washington.
Each kind of sensor gives different perspectives of an area or an issue. It is the educator's challenge to integrate this sensor capacity into required content areas. The information from these two kinds of sensor systems is made to order for social studies and biology competencies that inquire into the impact of society on itself and nature and its many biological systems. Such information is equally valuable for mathematics classes that need authentic data and real world context from which to teach mathematic procedures for carrying out deeper levels of analysis. This types of information resources can be localized for almost every classroom situation. Nearly every stream in the United States has USGS sensor systems on it, which can be found from the national and state maps at the USGS site. Nearly every community has multiple webcams hooked to the net. Classrooms can also cheaply buy webcams to hook to a classroom computer.
(For another view of this development, find the start menu in the top frame and see the double sensor demo which has been integrated with school activities in the top frame. One branch of this leads to in-depth information about the bridge project which includes school classroom activity.
Data from a sensor must not be thought of only in mathematical and scientific terms. Combining live interaction with humanly recognizable output, artistic work of great aesthetic quality can be produced. Proximity sensors provide just such an example. Their function is to measure the distance between two objects. They can be found in both analog and digital formats. One of their uses is to help set safety limits in the use of different kinds of machines. The proximity sensor is linked to other devices so that the physical measurement might be reported as a needle on a dial, text on a computer screen, or as a musical pitch to indicate the height, depth or closeness of an object. An audio or musical pitch is useful if visually reading a display is not possible or dangerous at times, such as for a pilot.
As an example of the creative relationship between science and art, early research into proximity sensors and the report of this data as an audio signal, led to the idea of electronic music and the invention of the first instrument that did not require physical touch, the theremin. Note the hand position in relationship to the antennae in the picture of the theremin. It is named after its Russian inventor Lev Sergeivitch Termen, who later changed his name to Leon Theremin. Once musicians learn the hand manipulation skills around the proximity sensor antennae, serious music can be performed. Peter Pringle has provided several examples of his theremin performances with this instrument that must be heard to understand the depth to which human creativity has taken this concept.
David Waxman's video demonstration of some rock music with a digital theremin-like device called the Solo Frame, shows some of the versatility of the concept. The Reach sensor ($100) extends this idea to almost any object that someone might reach for and then interact with, for example a plant, a flower vase, water fountain, sculpture or dancers.
Variations on the theremin instrument have been heard in settings as diverse as the Beach Boys band, Hollywood movie music scores, and symphonic concerts. Though not widely known, instruments are still being built and groups still gather to share performances. For example, a group of theremin musicians planned the Ether Music 2005 theremin music festival in Asheville, North Carolina on August 4-7, 2005.
Making human action the primary source of the sensor data has led to the use of sensors in museum displays and live dance performances. The i-Cube-X is one example of a a family of products used in many of these situations. Some sensors measure muscle response, some proximity. This in turn is fed to MIDI devices which can activate other kinds of media.
Preuss (2001) reports another interesting application. Global warming is in part the result of more and more carbon entering the atmosphere. SOLO is equipped with instruments for measuring organic and inorganic carbon, both in solution and tied up in particles. Some 3,000 of these carbon sensor systems will be placed afloat in oceans around the world, measuring and beaming their data back to satellites for years at a time. These same sensors are also being placed in tiny remote controlled submarines that programmed to leave and return to harbors and redirected by satellites, collecting not only data but actual samples of biomass for more detailed analysis.
The sensor then is just one element, though a key element, in many creations. These designs or electronic compositions include wires, switches, transmitters and sensors. The design might also include computer chips and mechanical parts such as gears and motors. Combine enough of these components together, and a robot is born.
The skills to compose in this fashion with sensors have produced an explosion of applications for art, math and science, educational administration, business and other content areas. The web site http://www.findasensor.com/ provides quick categorized sets of sensors for almost every conceivable application. What do you want to measure or manage today? Google's image database provides a view of thousands of sensors currently being used in the marketplace. (Find the start menu in the top frame and see the link to Google: Sensors.)
In spite of what has already been achieved, it is nothing compared to what is soon to come. Rapidly dropping prices, sizes and increasing capacities hint at enormous changes that will be coming as electronic composers use these new systems in their designs.
The inferences being made from numerous sources in the year 2003 are remarkably consistent (Hardy, September, 2003; for more, see Dust, Inc. press reports). Complete sensor units combined with a CPU, data storage and medium range wireless input and output are rapidly shrinking to the size of a grain of sand, approximately 1 mm on a side, and will sell for around a dollar. Units currently the size of a 9 volt battery now sell in the nine $50 to $100 range. With very low power consumption designed to last for many years, the wireless signal range of a single unit ranges from slightly longer than the length of a football field (100 yards) to a mile or more. Because such units will self-organize, passing information in bucket-brigade style from one to the next, then quickly shutting down to save power, a handful of such units could cover many square miles for years. What remains to be seen how soon an easy to use plug-and-play market will develop which does not require a programming background for basic design work. That is, once standards are set for attaching sensors of a particular size, designers could quickly construct a wide range of basic sensing systems much like children assemble Lego bricks. In fact, it is highly likely that toy manufacturers such as Lego would be among the early adopters of such technology in their products.
Sensors will become ever smaller. Sensor systems the size of grains of sand represent the next stage of sensor design. Nanotechnology points in the direction of even smaller systems, sensor systems the size of dust particles. Smith and Nagel's review of nanotechnology-enabled sensors (November, 2003) provides an excellent review of where current research is heading.
Prior chapters have used the structure of input, manipulation and output to address many types of composition. Before heading into the less well known territory of sensors and electronic design, let's review the familiar ground of the writer, the creator of text compositions. When writing with text, the composer is concerned with having a vision or concept of what he wants to accomplish. This is more complex than it sounds, because it requires a fair amount of experience in reading the text compositions of others so that one has models for where one might want to go or where one might want to diverge from past designs. This applies equally to photography or paint and draw applications and all the other forms of composition that have been explored so far. Vision leads to brainstorming about a variety of ways to accomplish the goal and then to an expansion of selected ideas into a visual or other multimedia grammar that is in a style that others can follow.
Working with sensors and related technologies and composing curriculum that will use them is no different. Composition often begins with a question or problem. The path to solutions to this question might involve finding an existing text document, a spreadsheet program or database. Composers need information. If the right composition does not exist, it will need to be created or composed, which leads the use of primary and secondary source materials. The more primary source materials are involved, generally the better and more reliable the composition is deemed to be. There is no resource more primary than data coming "live" directly from a sensor, often accurate to many decimal places.
In order to envision possible electronic compositions, one needs prior models. Today's current automobile, for example, is a rolling bathtub of sensors that report the status of brakes, tire pressure, engine temperature, fuel input, cruise control, security, or make emergency reports when occupants are disabled after a crash and so forth. What other things can sensors sense if attached to a wide range of devices? How many categories of sensors are available? Where does one get the sensors? What is the range of possibilities that fall within educational application and curriculum development?
In the next section, the focus will be on these input questions. The later manipulation section will focus on another question important to educators. Who can provide the skills for using sensors and how much training does curriculum composition in this area require? The output section will review ways in which educators are using the sensor data for educational benefit with the current curriculum. The multimedia composition section will reflect on how such technologies might integrate with the previously discussed areas of composition: text, image, animation, audio, video and 3D/virtual reality.
Where is sensor technology today? Sensors Magazine provides a SpecSearch with a comprehensive set of sensor categories and related chip sets. Browsing this forest of options is an education in itself. For more consumer oriented products aimed directly at schools, two major directions have been taken: calculator based and hand-held computer based. Most sensors that connect to calculators and hand-held computers are also available for desktop computers. Texas Instrument maintains their Data Collection Product Center which highlights their decade of experience in connecting school curriculum with calculators and sensors. The web site of Vernier Software and Technology reviews a wide range of sensors connected to handheld computers with a science and math focus.
Sensors are devices which can record subject specific data. There is an immense array of sensors that can be hooked to computers and other devices. These sensors might report the number of people who pass through a turnstile at the movies or be used by a bar code reader at the grocery store to indicate that the last can of tuna has been purchased and it is time to restock the shelves. When sensors are dropped in streams, they might report the level of water, its speed, temperature, water clarity, or the presence and percentage of disease causing bacteria such as coliform. The Hubble Space telescope is in essence an optical sensor controlled by earth-based computers. Several stunning remote-control developments with global impact can be found on the Internet and used in the classroom. Can you see their art, science, math and social studies implications?See -
Data loggers are small battery powered devices that are equipped with
a microprocessor, data storage and sensor. Most utilize software on a personal
computer to initiate the logger and view the collected data. Once the logger
is configured, it will be disconnected and placed where data collection
is needed. Onset Computer Corp (http://www.onsetcomp.com/)
is one company offering data loggers. Boxcar Software sets up the operating
parameters for Hobo and Stowaways, battery powered devices for remote placement
with sensors for temperature, RH (relative humidity), and light intensity.
Other companies include: http://www.geminidataloggers.com/
; http://www.dcpmicro.com/ ;
; http://www.pace-sci.com/ ;
http://www.microdaq.com
; http://members.tripod.com/~HANOVER_TECHNICAL/portable.html
.
Instead of manually bringing the data to the computer, another approach
is to use wireless technologies to automatically send data to a recording
computer. Davis Company offers such systems with a variety of weather type
stations with up to 15 different parameters being measured. Three system
of transmission are being used. Spread spectrum radio modems can send up
to 7 miles without a requirement for an FCC license. UHF radio modems can
send up to 25 miles but require FCC license. Cell phone modems would cover
infinite distances as long as they are within range of cell phone towers.
If standard electrical power cannot be used, solar-charged battery systems
are available. One system that Davis provides is a 6.5 amp-hour battery
and solar panel that once charged with 1hour of bright light can run the
station for 16 hours in total darkness. A fully charged battery will run
the system for about 8 days.
A variety of related but non-computer integrated systems are available. Sensaphone Systems provide frost alarms that phone several numbers until contact is made. Other sensors includ temperature, humidity, water detection, motion, magnetic reed switch for alarms and low temperature audible alarms. Additional sensors support temperature controllers hat turn fans and heaters on and off. Lightning detectors systems report distance away and frequency of strikes. Many PH meters are also available.
This is a very short section for a simple reason. Unlike the previously discussed categories, there is no software today that runs on a desktop computer that enables a novice with minimal training to design an actual sensor system or robotic device and output directions for its creation that a non-engineer could understand and build. This does indicate the opportunity for software development and grant proposals to develop such. There have been some simulation programs that explore the general process in a game like fashion, but such programs have not had staying power in the market. There are also a variety of project kits for all kinds of sensor and robotic projects, but these generally could not be completed in the time of one evening course, say 3 hours. Such kits also presume a number of electrical and electronic skills not possessed by most students and educators. The shortest route to the creation of such a system for an educator is to partner with high school electronic courses and higher education programs training electronic and electrical engineers and explain the kinds of designs that are needed. Sometimes these are within range of course projects for students.
I can also make those contacts for you. Do not put several ideas on one message. Please leave a different message for each concept that you have. Discussion board: What kinds of electronic designs that might or might not integrate sensors with motors and gears would you like to see for educational settings, whether intended for classroom or administrative use?
That said, there are curriculum materials that introduce electronics and the use of sensors (see Circuit Sense below) and educational and business products that incorporate sensors in their use.
Some uses of sensors are ready for purchase and integration with minimal training. Many projects involve a basic knowledge of computer programming. All involve a certain amount of simple understanding of circuits and electrical design. The following sections provide a short introduction to automation, computer programming, sources of kits and projects and finally, suggested sources of training and curriculum materials.
Beginner Curriculum (K-adult)
Advanced Curriculum for Sensor Use
Funding/Grant Resources
- Electronic Industries Foundation, a link to funding sources for curriculum work in this area and from time to time a funding source themselves. The foundation is the not-for-profit sector of the Electronic Industries Alliance (EIA), the philanthropic arm for this federation of 5 associations comprising over 2,100 U.S. electronics, telecommunications and hi-tech companies.
Products
- Thomas Register. This company provides a very comprehensive catalog of manufacturing products. Though you must have a user name and password to use their catalog, you can get one for free by filling out their registration form. Once at their home search page, search for the word sensor to retrieve hundreds of types of sensors and contact information for the companies that sell them. These sensors could be hooked to devices connected to computers. If you would like for someone with electronics background to wire a sensor to your classroom computer, ask for such a person through your school newsletter and generally a parent with electronics background will take an interest in your project.
Home automation makes use of a wide variety of sensors to manage the operation of a home. It is perhaps the most common system that educators might find themselves considering that uses sensors and remote control devices extensively. Most home supply stores provide a variety of technology and training in this area. So much information is available online for this topic that searches are probably best paired with some other concept such as "home automation" and garage. See the following examples: Google search for "home automation" Google search for "home automation" and garage
If you merge a collection of sensors, mechanical devices, and programming languages you have a high interest topic for students, robots. Much has been written in both fiction and non-fiction concerning this concept for most age levels. Defining a robot is an elusive task, but clearly the capacity to carry out automated functions in your absence is one part of a robot. Others would include environmental awareness, communication capacity and mobility as important features.
Programming is an important part of using sensors whether part of a robot
or not. Programming can be done with written text and it can be done with
hardware. To an application programmer, hardware is a kind of frozen software.
To an electronics engineer software is just a slow kind of hardware. That
is, wires, solder, sensors and computer chips are continually designed
by electronics engineers to carry out a variety of computer programs. Today,
our country is short some several hundred thousand people with computer
science training to work in this career area. Projections of need run to
over a million positions in the next few years. Children and adolescents
could greatly benefit with earlier and more exposure to a variety of by-products
of computer science that incorporate elements of programming. Logo has
been the the premier language for introducing school age children and adolescents
to programming concepts, but any programming language is better than no
language. Especially if the teacher lacks programming skills, these sites
are examples of places that can provide awareness and further education
for a wide range of learners.
When these sensors are integrated with other elements such as mechanical devices and programming languages, robots are formed. A number of resources are available for school curriculum in this area:
Since most readers of this chapter will not have the electronic and electrical engineering type skills to create their own web based sensing projects that report data to a web page, it is useful to be aware of live sensor systems currently connected to the Internet that can be incorporated into existing web page and frame page designs.
| The Network has: | Parts of the network body. | Where to Buy? |
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| Ears | I need some sites that use a microphone connected to our computer to
respond to our voice. Can you help? Outside of specific web sites, Netscape
4.0 in general has a Conference feature that allows you to make Internet
telephone calls and share a whiteboard for drawing and markup using its
Conference feature, if you have a microphone.
Such electronic sensors are common but I need some web sites that can demonstrate the live detection or measurement of sounds. Please do a web search. Can you find anything new? [Use the right search technique to hunt for the phrase "electronic ears" and as of November 17, 1998 Alta Vista found 79 pages that used this phrase. Are there other search term or phrase? Try ultrasonic sensors.] Hawaii-2 Observatory (H2O) located over 3 miles deep (16,400 feet) in the Pacific Ocean currently with seismometer and hydrophone. |
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| Motion (Hands & Legs) |
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| Skin and Internal Systems |
meters. |
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| Eyes |
WCU web cams: Hunter Library Computer Lab ; (Does anyone know of more?) |
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| Voice |
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| Nose | Thought. What scent should pervade your web site?
Think of the nose as a sensor for gases. Electronic sensors for gases are available (e.g., smoke detectors) but connecting them to computers can be more expensive. Projection of smells via computer requires smell synthesizers attached to your personal computer and these are still in development, but close to being marketed. I need some web sites that can demonstrate the live detection and/or broadcast of gases (smells). Can you find anything new? Please do a web search. Several search terms are useful: electronic nose; gas chromatography; smell camera; chemical olfaction; smell generators; odor synthesizers; aromatherapy. Here are some sources of information found so far: Selling smell synthesizers: E-Noses & Their Applications ; Review: the Electronic Nose, worldwide. Article: Charles Platt, "You've got smell!" Wired, (Nov. 1999). pp.257-263. Quote: "A typical scent using the Bellenson-Smith encoding format, can be defined with less than 2 Kbytes of data." Google search for "electronic nose".
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| Tongue | Univ. Texas research:Electronic
Tongue articles. Think of the tongue as a sensor for liquids. Such sensors are
common but I need some web sites that can demonstrate the live detection
of acidity, salt levels and so forth. Please do a web search. Can you find
anything new?
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| Internet-related Compositions that integrate most or all of the above. | The Millenium Bug ; the email story behind the bug that demonstrates the nonlinear serendipity of the Net. |
The sensor data might be displayed in web compositions as one frame of a web page, an inline frame or a pop-up page. But the overall technique is not as important as having a style guide to its integration. Earlier in this online textbook, the National Geographic strategic was discussed for integrating text and images. Recall that their articles begin with very large images and limited text and then scale down images and scale up text over the length of an article. What strategy would appear to be most useful for integration sensors into a composition?
The scaling down strategy works well for images. An image can provide a a quick overview of the whole and set the theme or direction of a composition. Such a strategy could be used for sensor integration. That is, the beginning of a composition might show a stream or table of data or graph from a sensor and a related article that explains what the graph or data set means.
Because such presentation of sensor data is often not as self-explanatory as a photograph, there is another integration strategy for sensors that makes sense and that also has a traditional role in text publishing, as evidence in support of a point. That is the sensor data might be integrated as a kind of citation that would indicate the presence of sensor data, the nature of the data and the date on which the author noted that this system was functioning. That is, if one is discussing the beauty of a harbor scene in Australia, a live web cam view (light and optical sensors) across the harbor of the opera house in Sydney (live sensor, Sydney opera house web cam, November 17, 2003) would be used. If one was preparing a report on the regular periodic fluctuations of a local stream, one would reference the Geological Survey data coming from that stream (live sensor, Tuckaseigee water depth, November 17, 2003).
A similar example is the Greenville Bridge Site Story. In this two frame composition, the top frame leads to webcam shots of the construction area and other related curriculum materials. The bottom frame provides live web data of the current water level and leads to the presentation of other information as well.
Larger compositions will be created from a larger collection of images. For example, a three-dimensional graph might be created from current data with the click of a mouse that would activate a current collection of the information from multiple sensors. Though I have no example, such reference would require another special type of citation that could be done with the standard scripting language with Microsoft Excel or other scripting languages (example: live sensor collection, Kansas weather map, November 17, 2003). This would require some programming skills with a web focused language like PERL or PHP.
The above Output section of this page provides numerous examples of web sites reporting currently data an intervals of live to hours to days. These sources make excellent elements for creating your own web page compositions that integrate sensor data. For those interested in the challenge of making their own sensor projects that report to the web, refer to resources listed in the Manipulation section above.
The scale-down and the evidence reference strategy are just two possible approaches for integration of sensor information. Sensor information has also been used as components of larger compositions. For example, audio or musical sounds have been created using live sensor data, from simulation wind chime sounds to coordinate values that guide the movement, pressure and colors of a pen that draws images.
A weather based example could provide a model for a uni-media composition. Text information would supplement the various media elements. A map with hotspots would guide the viewer to different perspectives. An animation of satellite photos would show weather movements over the last several hours. Still images taken from live web cams would be arranged in a table to show past and current weather conditions. A series of two or three dimensional map from a GIS program would show where the weather might impact various structures or events across a region. A musical wind chimes might use real data that plays softly in light winds and add more and louder chime sounds as the wind speed increases. Video and audio files could play TV news channel weather reports from an archive or be provided live as they occur. A three dimensional graph based on live weather data might further enhance the information story and would require some further text explanation for those not familiar with its representations.
Though the web is an important form of digital publication, one must not overlook that ultimate electronic composition. Incoming sensor data might also be used to guide the activity and work of a robot or robotic devices, whether for aesthetic or work activity.
Bibliographies: Still - Audio - Video - 2D - 3D - Sensor - interact - MM
Sensor Magazine, a trade magazine for scientists and engineers about sensors.
Sensors
and Actuators B: Chemical, An international journal devoted to research
and development of chemical
transducers
Chamberlin, Sean (2003). The remarkable ocean world: The Gaia hypothesis. Intelligent Communications. Retrieved November 10, 2003 from http://www.oceansonline.com/gaiaho.htm
Hardy, Quentin (September 1, 2003). Sensing Opportunity, Forbes.com, Retrieved November 17, 2003 from http://www.forbes.com/free_forbes/2003/0901/107.html
Saffo, Paul (April 15, 2002). Smart Sensors Focus on the Future, CIO: Insight. Retrieved November 9, 2003 from http://www.cioinsight.com/article2/0,3959,2132,00.asp
Smith, Sharon & Nagel, David (November, 2003). Nanotechnology-Enabled Sensors: Possibilities, Realities, and Applications Sensors Online Magazine, Retrieved November 17, 2003 from http://www.sensorsmag.com/articles/1103/22/.
Preuss, Paul (February 21, 2001). CO2 sensors: Climate Change Scenarios Compel Studies of Ocean Carbon Storage. Berkeley Lab. Retrieved July 2, 2003 from http://www.lbl.gov/Science-Articles/Archive/sea-carb-bish.html
I-cube-X http://infusionsystems.com
To cite this page:
Houghton R.S. (2003). Chapter Seven: Sensors and Electronic Remote Control. In Multimedia Education. Retrieved (current date here) from http://ceap.wcu.edu/houghton/MM/Ch7/Ch7mmframes.html