Smart Systems And Smart Materials

Smart Systems And Smart MaterialsScience and engine room has made abominable developments in the design of electronics and machinery by using standard genuines, which did not go for particularly special(a) properties (i.e. steel, aluminum, gold etc). Imagine the come out of possibilities, which outlive for special type of substantives that bring forth properties scientists merchant ship manipulate. slightly much(prenominal) heartys has the tycoon to ad estimablement fix or size or simply by adding a little bit of heat, or to turn from a liquid to a solid al about instantly when it is near a magnet these materials be called anguish materials.Smart materials ar the materials that nurse one or to a greater extent properties that maroonwork be dramatically altered. Most everyday materials have somatogenic properties, which do-nothingnot be signifi arsetly altered for example if an oil is heated it shall engender little thinner, whereas a refreshed material wi th variable viscosity may turn from a liquid which flows substantially to a solid. A florilegium of chicness materials already exists, and is creation researched extensively. These includes piezo electric materials, magneto-rheostatic materials, electro-rheostatic materials, and shape memory alloys. well-nigh everyday items atomic procedure 18 already incorporating pain materials (c saturnineeepots, cars, the International Space Station, eyeglasses) and the bit of applications for them is growing rapidly.Each individual type of suffer material has a antithetic type of property which can be significantly altered, such(prenominal) as viscosity, volume, and conductivity. The property which can be altered influences what types of applications the smart material can be utilise for.Smart constitutions and smart materialsSmart expressions ar the new emerging materials brasss which combines contemporary materials scholarship with information science. The smart system is composed of these- sensing, processing, actuating, feedback, self-diagnosing and self-recovering subsystems. These system uses the operable properties of advanced materials to achieve gamy carrying outs with the capabilities of recognition, discrimination, and adjustification in response to make change of its environment. Each component of this system mustiness have functionality, and the entire system is integrated to perform a self- manipulateled smart action, similar to a living creature that can think, make intellect and take actions. A smart system can be considered as a design philosophy that emphasizes predictivity, adaptivity and repetivity. A smart system/structure is defined as a non-biological physical structure having the following attributes(1) a definite purpose(ii) means and imperative to achieve that purpose and(iii) a biological pattern of functioning.Smart materials atomic number 18 the subset of the smart systems, i.e. smart structures at the microscopic or mesoscopic scales. Smart systems be the non-biological structures which means that the system functions as a biological system rather than the pattern of functioning as a Turning machine.These materials will generally include at least one structural element, some for means of sensing the environment and its get state, and some type of processing and adaptive withstand algorithm. Science and technology in the 21st century will have to rely to a great extent on the development of new materials that ar expected to respond to the environmental changes and manifest their k right awayledge functions according to the optimum conditions. The development of these materials will doubtlessly be an essential task in some playing areas of science and technology such as informatics science, micro-electronics, computer science, health check treatment, breeding science, energy, transportation, caoutchoucty engineering and military technologies. Materials development in the future, theref ore, should be say toward creation of hyperfunctional materials which will surpass even biological organ in some aspects. The present materials research is to develop various pathways that will pencil lead the modern technology towards the smart systems.Types of Smart MaterialsPiezoelectric materials-Piezoelectric materials have two unique properties that are interrelated. When a piezoelectric material is deformed, it gives off a small but a measurable galvanic discharge. Alternately, when an electrical current is passed with a piezoelectric material it experiences the significant gain in size (approx. up to a 4% change in volume)Piezoelectric materials are simplely used as sensors in opposite type of environments. They are often used to measure facile composition, fluid density, fluid viscosity, or the top executive of an impact. An example of a piezoelectric material in everyday tone is an airbag sensor in our car. The material senses the force of an impact on the car a nd thus sends and electric charge deploying the airbag. grammatical case of Piezoelectric materialsElectro-rheostatic (ER) and magneto-rheostatic (MR) materials-Electro-rheostatic (ER) and magneto-rheostatic (MR) materials are fluids, which can experience dramatic change in their viscosity. These type of fluids can change from thick fluids (similar to motor oil) to nearly a solid substance within a span of a millisecond when exposed to a magnetic or an electric dramatic art. The effect can completely be reversed just as quickly when the field is removed. MR fluids experience viscosity changes when exposed to a magnetic field, while ER fluids experience similar type changes in an electric field. The composition of severally type of smart fluid varies widely. The most common form of MR fluid consists of the tiny iron particles suspended in oil, while ER fluids can be as simple as milk chocolates or corn-starch and oil. MR fluids are mostly being developed for use in the car shocks, damping slipstream machine quivering, prosthetic limbs, exercise equipment, and surface polishing of machine parts. ER are mainly being developed for use in the appreciation and valves, as well as engine mounts designed to reduce make noise and vibration in the vehicles.Shape memory alloys-Shape memory alloys (SMAs) are the metals, which exhibit two intresting unique properties, pseudo-elasticity, and shape memory effect. Arne Olander first notice these unusual properties in 1938 (Oksuta and Wayman 1998), but until the 1960s were no any sound research advances made in the field of shape memory alloys. The most effective and widely used alloys includes-NiTi (Nickel Titanium), CuZnAl, and CuAlNi.The unusual properties mentioned in the above are being applied to a wide variety of applications in the number of incompatible fields.Shape memory alloys use) pH huffy polymers-pH sensitive or pH responsive polymers are the materials which responds to the changes in the pH of the su rrounding medium by varying or changing their dimensions. much(prenominal) materials either swell or collapse depending on the pH of their give birth environment. These behaviour are exhibited due to the presence of certain type of functional groups in the polymer chains. on that point are whole two kinds of ph sensitive materials- one that have acidic group (-COOH, -SO3H) and swells in basic pH, and an separate(prenominal)s that have basic groups (-NH2) and swells in acidic pH. Polyacrylic acid is an example of a spring and Chitosan is an example of a latter. The mechanism of response is just same for both, just the stimuli varies. Their response is triggered due to the presence of ionisable functional groups (eg -COOH, -NH2) which get ionized and acquires a charge +/- in a certain pH. The polymer chains are now having similarly charged groups which causes repulsion and thus the material expands in dimensions. The diametral of this happens when pH changes and the functional g roups loses their charge hence the repulsion is therefore done for(p) and the material collapses back. These materials are being widely used for program lineled drug language systems and biomimeticsHalochromic material-Halochromic materials are the materials which changes colour when pH changes eliminates. The termination chromic is defined as the materials that can change their colour reversibly in the presence of a factor. In this case, the factor is pH. The pH indicators have this type of property.Halochromic substances are conform to for use in environments where pH changes occur very frequently, or the places where changes in pH are most. Halochromic substances can detect alterations in the acidity of substances, eg- maculation of corrosion in metals. These substances can be used as indicators to hold back the pH of the solutions of un cognize pH. The colour obtained is compared with the colour obtained when the indicator is mixed with solutions of known pH. The pH of th e unknown solution can then be estimated. patent disadvantages of this type method include its dependency on the colour sensibility of the human eye, and those of unknown solutions that are already colour can be used.example of halochromoicThe colour changes of halochromic substances occur when a chemical binds to existing heat content and hydroxide ions in solution. such bonds result in changes in the meld systems of the molecules, or the range of electron to flow. This alters the amount of light absorbed, which in turns results in a visible change of colour. Halochromic substances does not display a extensive range of colour for a liberal range of pH because, by and by certain acidities, the conjugate system does not changes. The various shades resulted from different type of concentrations of halochromic molecules with the different conjugate systems.(6)Dielectric elastomers (DEs)- Dielectric elastomers are the smart material systems which produces large strains (even up to 300%) and belong to the group of electro active polymers (EAP). establish on their simple principle of working dielectric elastomers actuators (DEA) transform electric energy directly into the mechanical work. DE are lightweight, and have a high elastic energy density and are investigated since the late 1990s. Many of its probable applications exist as prototypes. Every year in spring a SPIE conference takes place in San Diego where the newest research results concerning DEA are exchanged between.Self-healing materials-These materials are the class of smart materials that are having the structurally incorporated ability to ameliorate damage caused by mechanical tradition over date. The inspiration comes from the biological systems, which have the ability to heal after being wounded. Initiation of cracks and other types of damage on a microscopic level have been shown to change the thermal, electrical, and acoustical properties, and eventually lead to the whole scale failure o f these materials. Usually, cracks are mended by hand, which is onerous because cracks are often hard to detect. A material (polymers, ceramics, etc.) that can intrinsically correct the damage caused by normal usage could lower production costs of the number of different industrial processes through longer part lifetime, reduction of inefficiency over time caused by degradation, as well as prevent costs incurred by material failure. For a material to be called as self-healing, it is necessary that the healing process shall occur without human intervention. examples shown below include healing polymers that are not self-healing polymers.Example of self healingTemperature-responsive polymer-Temperature-responsive polymer is a polymer which undergoes a physical change when an orthogonal thermal stimulus is presented. Their ability to undergo such changes under easily controlled conditions makes this class of polymers fall into the category of smart materials. These physical changes can be exploited for many analytical techniques, especially for separation chemistry. After many investigations of poly(N-isopropylacrylamide) (poly-NIPAAm), there was a sparked interest in the applications of this and many other stimuli-responsive polymers. There have been extensive research in the applications of intelligent polymers for use as stationary phases, extraction compounds, surface modifiers, drug delivery, and gene delivery.Temperature responsive polymerApplications of smart materialsThere are many possibilities for smart materials and structures in this world. Engineering structures can be operated at the very limited of their performance envelopes and to their structural limits without fearfulness of the exceeding either. These structures can also give maintenance engineers a full report on the performance history, as well as the fix of the defects, whilst having the ability to counteract the unwanted or potentially dangerous conditions such as excess vibration, and effect self repair.Smart Materials in Aerospace-Some materials and structures are termed sensual devices. These are structures which can sense their environment and receive data for use in health and usage observe systems (HUMS). forthwith the most well established application of HUMS are in the field of aerospace, in the areas such as aircraft checking.An aircraft constructed from a sensual structure could self-monitor its performance to a level beyond that of current data recording, and provide ground crews with the enhanced health and usage supervise. This would minimise the overheads associated with HUMS and allow such aircraft to evaporate for more hours before any human intervention is required.Smart Materials in Civil EngineeringThey can be used in the monitoring of civil engineering structures to assess durability. Monitoring of the current and long term behaviour of a bridge would lead to enhanced safety during its life since it would provide early warning of struc tural problems at a fix up where minor repairs would enhance durability, and when used in conjunction with structural refilling can be used to safety monitor the structure beyond its original design life. This will influence the life costs of such structures by reducing upfront construction costs and by extending safe life of the structures. Sensual materials and structures also have a wide range of potential domestic applications, as in food packaging for monitoring safe storage and cooking.The above example addresses alone sensual structures. However, the smart materials and structures offer the possibility of structures, which not only sense but also adapt with their environment. Suchtypes of adaptive materials and structures benefit from the sensual aspects highlighted earlier, but in addition have the capability to move, vibrate, and exhibit a multitude of other real time responses.Potential applications of such adaptive materials and structures range from the ability to con trol the aeroelastic form of an aircraft wing, thus minimising drag and improving operational efficiency, to vibration control of lightweight structures such as satellites, and power pick-up pantographs on trains. cognisance MaterialsMechatronic smart structures have demonstrated the capability of its technology, but raise the Copernican issue of the complexity of the resulting system. This smart type of structures contains a multitude of different materials, and in the case of sensual structures it will generate large amounts of data. This ontogenesis in complexity has been described as the spaghetti syndrome, and has led to the proposal for an substitute type of smart structure based on the theory of pot materials (the Chinese characters which means wisdom, structure, monitoring, integrating and benignity is being pronounced raft in the Japanese language). Such structures will move functional integration into the constituent engineering materials by themselves.Some of the p ractical examples of ken materials exist at present, although a structural composite based on this concept had been developed in Japan. This is a carbon and glass fibre strengthened concrete which able to monitor concrete structures by using only the structural reinforcing fibres, thus reducing the complexity of the system.(4) Structural Uses(a) Active control of structuresThe concepts of the adaptive behaviour have been an underlying theme of active control of structures which are subjected to an earthquake and other environmental types of loads. The structure adapts its dynamic characteristics to sports meeting the performance objectives at any instant.Sun and Sun (vi) used a thermo mechanical approach to develop a constitutive relation for change form of a composite beam with a continuous SMA fibers embedded instance to neutral axis. The authors finally concluded that SMAs can be success amply used for the active structural vibration control. Thompson(iii) also conducted an an alytical investigation on the use of SMA wires to dampen the dynamic response of the cantilever beam constrained by SMA wires.(b) Passive control of structuresTwo families of the passive seismic control devices which are exploiting the peculiar properties of SMA kernel components has been implemented and tested within our MANSIDE undertaking (Memory Alloys for New Seismic Isolation and Energy Dissipation Devices). They are the particular(a) braces for the framed structures and isolation devices for the buildings and bridges.(c) Smart Material TagThese smart materials tag can be used for composite structures. These tags can be monitored externally throughout the life of those structures to relate the condition of internal material. Such measurements as stress, moisture, voids, cracks and discontinuities might be interpreted via a remote sensors.(d) RetrofittingSMAs can use as self-stressing fibres and therefore they can be applied for retrofitting. Self-stressing fibres are the on es in which the reinforcement is placed into the compositenon-stressed state. A prestressing force is therefore introduced into the system without the use of large mechanical actuators, by providing SMAs. These materials thus do not need specialized electric equipments nor do they create safety problems in the field. Treatment can be applied at any time after hardening of matrix instead of during its curing and hardening. So the want or short term prestressing is introduced by triggering the change in SMAs shape using temperature or electricity.The FutureThe development of true smart materials at the small atomic scale is still progressing a little, although the enabling technologies are under the development. These require the novel aspects of nanotechnology (technologies which are associated with materials and processes at the nanometre scale, 10-9m) and the fresh developing science of shape chemistry.Worldwide, a considerable effort is being made to develop these smart material s and structures. The technological benefits of such types of systems have begun to be identified and, demonstrators are therefore under construction for a wide range of applications from space to aerospace, to civil engineering and to domestic products. In many of above, these applications, the cost benefit analyses of such systems are yet to be fully demonstrated. The Office of Science and Technologys Foresight Programme has recognised these types of systems as a strategic technology for the future, having considerable potential for creation of wealth through the development of various unknown products, and performance enhancing the existing products in a broad range of the industrial sectors.The concept of engineering materials and structures which respond to their own environment, including their human owners, is somewhat an alien concept. So it is therefore not only important that the technological and financial implications of these materials and structures are addressed, but also issues associated with cosmos understanding and bankers acceptance.Techno-democracy could only come about only through pedagogy and exposure of the general public to these technologies. However, such a general acceptance of smart materials and structures may in fact be more difficult than some of the technological hurdles which are associated with their development. A new smart materials process Multiple Memory Material Technology developed by University of Waterloo engineering researchers promises to revolutionize the manufacture of diverse products such as medical devices, microelectromechanical systems (MEMS), printers, hard drives, automotive components, valves and actuators.