Starting from the first peg legs and hand hooks, and ending withthe modern robotic and myoelectricprosthetics, the prosthetics were highly improved and developed. The ancientEgyptians were the first culture who have used the prosthetic technology.1They have made the prosthetic limbs of fiber.1TheGreville Chester Toe was made up of cartonnage and contact onto the foot infashion to Egypt sandals. 2 Cartonnageis a material comparable to paper and is made of layers of linen or papyruscovered in plaster. 2 The purpose from thisprosthetics was to maintain physical wholeness in both their lives on Earth andin the afterlife.Scientists think that most of these prosthetics in the past werenot functional prosthetic and they were used only for cosmetic reasons,although a new discovery of a prosthetic toe in an Egyptian mummy says that itcould be a functional prosthetic.
1 In 1858, an old artificial leg was discovered at Capua, Italy. Thisartificial leg was made of bronze and iron, with a wooden core. It is dating toabout 300 B.C.1Ambroise Paré who was working in the French Army as a surgeon isthe father of modern prosthetic surgery.1 At 1529 he popularized new amputation procedures to the medical community.
1At 1536 he had created prostheses forupper and lower amputees.1 He had also created an above-knee device which was adjustable andhad fixed position, actually this device had a lot of features that are used innow in medical devices.1 This above-knee device is shown is figure1. Figure1: The above-knee device that has been created by Ambroise Paré.1 After the World War II, The needing ofdeveloping new Prosthetic has been increased.1The government of United States of America has made a contract with companiesto develop prosthetic.1 Today’s modern devices have less weight,and consists of different types of materials with modern microprocessors andcomputer chips.1 Prosthesesbecome more realistic by covering it with silicone to be able to mimic theappearance of real limbs to provide amputees with the most functional devicesand help them to return to the normal lifestyle.
1 Prostheticdevices are common in both medical and engineering fields. 2 These days many parts ofa body can be replaced by a prosthetic. 2 Manufacturing process of prosthetic limbsbecomes precise task to choose a certain material that fit particular needs ofa user’s and improving their quality of life which they can’t achieve theirtasks due to their disability.2- Myoelectric Prosthetic: Figure2: Examples of different types of Myoelectric hands a.OttobockDMC Plus. b.
Touchbionics iLimb. .3 In 1940s and because of the highly development in computer devices and the algorithms science, Myoelectric upper limbs prosthesis has been developed.3 A Myoelectricprosthesis is a special type of prosthesis which uses the electrical tensiongenerated by a muscle contraction as order to move. 3 Amputee’s will be able to controlprosthesis using one muscle group to open a hand and the other muscle to closethe hand, some advanced systems could provide movement in wrist. 3 Some differenttypes of Myoelectric prosthesis are shown in figure 2.
In the mid-1970s a special pattern has beendeveloped to analyze the useful information that is presented in theelectromyographic (EMG). 3 This information could be used to make more movements in different degrees. Thistechnique is not widely used these days because it needs high processing power. 3 Some disadvantages of this prosthesis is during daily living the armcould be affected by several changes, like re-positioning of the electrode whichcould affect the accuracy of pattern recognition. 3 Figure3: Asimple illustration of the control strategies for Myoelectric prosthesis.
3 The advantages of changing intensity of muscular contractions has beenused to design a type of this prosthesis which known as on/off control or crispcontrol prosthesis. 3 AnActivation thresholds determine the actions of the Myoelectric prosthesis. 3 For example if the muscle slightly contractedthe hand Myoelectricprosthesis will close. If the muscle strongly contracted the hand Myoelectric prosthesis willopen. If no contraction occurred in the muscle the prosthesis will be slightly contract.
Figure 3 shows a better illustration for this example. More movements in different degrees could be evolved if different muscle group and more electrodes havebeen used. 3 X-Actions fromthoughts:Neuroscientists for a long time have interested in using brainsignals to control artificial devices. x123 One of the mostimportant technique which is used to do this call hybrid brain–machineinterfaces (HBMIs).
x123 “The word ‘hybrid’ reflects the factthat these applications rely on continuous interactions between living braintissue and artificial electronic or mechanical devices”.x123 TheHBMIs combine two types of application, the first type of HBMIs is a human-madedevices which generated electrical signals and transmit it to the brain tissue inorder to transmit some specific type of sensory information to mimic areal human nerveand sensory function. x123 An important example for thistype is an auditory prosthesis. x123 The second type of HBMIs is athe real-time and processing of the brain activities to control artificialdevices. An important example for this type would be the using of neuralsignals from the motor cortex to control the movements of a prosthetic arm orleg in real time.
x123 A general description and organization of atype 2 HBMI is shown in figure 2 .The applications that require alternateinteraction between the brain and artificial devices will have both type 1 and2 HBMIs. x123 Figure2:A general description and organization ofthe type 2 HBMI .x123 Unfortunately, the common non-invasive electrophysiological methods to measure the electrical activity of theneurons in cortex, such as scalp EEG recordings, lack the required resolutionwhich needed to control a robotic arm in real time.
x123 For thisreason, multichannel intracranial recorders of brain activity are surgicallyimplanted to provide a raw brain signals to use it in the HBMIs. x123It is important to design an appropriate instrumentation for recording andprocessing the raw brain signals in real time. x123 This could bedone using VLSI chips, VLSI is defined as : “very large-scale integration,the process of integrating hundreds of thousands of components on a singlesilicon chip.”x123 This neurochip must be small tobe implanted it in patients and it must work with replaceable batteries.x123 It must be also wireless.x123 A prototype of this neurochip is shown infigure 3. Figure3: A prototype of neurochip for processing brain signals.
x123 After the processing and analyzing of signal was done using theneurochip, the neurochip sends the data to robotic prosthetic processer, usingthis data and by using some specific mathematical algorithm, the roboticprosthetic processer compute the three-dimensional movement and start to move.x123 Figure4 shows a brief explanation of neurorobotic prosthetic working method. Figure4:A brief explanation of neurorobotic prosthetic working method.
x123X-Flex-Foot: Figure5: Flex-foot is used in running competition. x321In 1984 the first Flex-Foot was invented. x321 The purpose of this developed prosthesis is tomake better rehabilitation for an amputee and make them able to run and to let them compete in running competition.x321 A runningcompetition for amputees is shown in figure 5. x321 Thisprosthesis is made from carbon fibre which is light-weight and strong material. x558x321 The Flex-Foot was designed in away that makes it gives more deflection, which improves the mechanism ofrunning. x321 Like a spring, the Flex-Foot can store kinetic energy from theamputee steps’ as potential energy, which help the amputee to run and jump more easily.
x321This type of prosthesis has obviously evolved in the last years. x321 A brief development history of theFlex-foot is shown in figure 6. x321 Figure6: The development historyof the Flex-foot. x321 The Flex-Foot is better than normal prosthetic, because it provideshigher walking and running speeds and consume less energy.
x321 The producer offers 18 different types of this prosthesis, everytype is different from the other in the stiffness. x321 The right type is chosen according to theweight of the athlete. x321