Abstract:Our project aims to design an ankle-foot exerciser which provides alternate plantar and dorsiflexion movement to the foot. It makes use of passive motion enabling the patients to flex and stretch their ankle muscles by strong force to support the weaker ones by moving in a controlled manner. The key principle applied are irradiation which involves in neuronal excitation over the weaker ones, by varying the graded resistance to enhance contraction. This is to stimulate the affected nerve that is without dorsiflexion motion. By pedaling, the movement of joints is enhanced, as a result the joint muscle gets required energy to work in case of foot drop. There is a weakening on one side and overloading occur on the other side achieving plantar flexion position . On the other hand upper leg muscles become rigid weakening the lower part. This in turn assists dorsiflexion motion which leads to stimulate and allow rigid muscle to stretch. Then the EMG signals are viewed in lab view software to know the improvement of this process.INTRODUCTIONFoot drop is a severe complication arising from various physiological malfunctions concerning the musculoskeletal system. For a better recovery, an AUTO ANKLE FOOT EXERCISER can be preferred about which is dealt in this paper. This technique aids in reforming the gait activity of the weak muscles to enhance normal muscle movement of the patients. Using a labview software, the acquired EMG recordings are interpreted. According to statistics, the percentage of sufferers of foot drop is about 80% in India. It happens to be the age group between 20 and 50 years. As per Walter Reed Medical Centre, nearly 20,000 ankle sprains are reported per day in the States. Out of the adults in the States, about 83% suffer an extremely severe foot pain as reported by the American Podiatric Medical Association. OVERVIEW Foot drop treatment involves various types which are preferred as per the impending condition of the severity. Peroneal nerve stimulation is suggested in case of the cause being hemiplegia. In case of direct trauma-prone foot drop, surgical repair of dorsiflexor muscles is recommended which enables rectification of gait activity by a short burst of electrical stimulation controlled by a switch at the heel of target limb. In the case where the nerve insults being the cause, restoring nerve activity by removal of the cause is suggested. A pharmacologic therapy using laparoscopic synovectomy can be done in case of chronic paresthesias. Erythropoietin can be used to relieve pain in the damaged nerve. Other alternate ailments like transdermal capsaicin,amitriptyline, nortriptyline can also be preferred. Ankle Foot Orthosis is a remedy when surgery is not an option of cure and is used to proffer dorsiflexion of the toe on a swing phase and medial or lateral stability of ankle on a stance phase. A surgical intervention is prevalent when foot drop is present at lumbar disc herniation as it may lead to loss of blood supply at nerve root due to reduced flow of blood. In such situation, the nerve is more prone to compression than peripheral nerves. Foot drop as result of pelvic replacement can be treated sciatic nerve decompression.BACKGROUNDThe technique used in an Automatic Foot Exerciser to reform the lost nerve activity uses an automatic pedal that functions at some specific angles and supports in renovating the nerve activity automatically and straightens the gait activity of the affected at a faster rate than the above-mentioned treatments. An Arduino Controlled Motor suffice the working of the exerciser. Whenever the patients do their workouts, there is room for recording the EMG from deep peroneal nerve at the same time that offers proper recognition of the progress of the treatment. This system improves the accuracy of cure, offers less labor and cost efficient. The auto mode pedal works at a fixed angle with a delay being programmed to the Arduino module.STRUCTURE OF FOOTThe foot is the terminal part of the leg that helps in various mechanical movements of the body. It is composed of more than hundreds of tendons, ligaments, and muscles along with the bones giving proper shape to it. It is stiff and stronger as it is responsible for bearing the body weight. Calcaneus forms the large part of the foot that slides upwards meeting tarsal bone and downwards to meet the rest of the bones. There are also arches of the foot namely the medial arch, the lateral arch and the fundamental longitudinal arch that form three curves making the walk easier. They are strengthened by means of tendons and ligaments. The bones involved are the tarsal, metatarsal bones and phalanges. The articulations of the muscles at the ankle offer flexibility and maintenance of a balance of body weight. DEEP PERONEAL NERVEDeep peroneal nerve arises from the bifurcation of the sciatic nerve at popliteal fossa as common fibular nerve which terminates as superficial and deep fibular branches where the latter develops as peroneal nerve. The deep fibular nerve terminates further at the dorsum of the foot into two branches as lateral and medial. The former supplies motor neurons to intrinsic muscles of the foot while the latter accents nerves to the skin between the first and second toes.MOVEMENTS OF THE ANKLE DORSIFLEXIONDorsiflexion is the bending of the foot in the upward direction involving toenails.PLANTARFLEXIONPlantarflexion is the ankle joint movement in the downward direction or the movement of toes curling down the sole.FOOT DROPFoot drop is a discomfort caused due to inability to lift the front part of the foot which in turn leads to trailing of forefoot and toes on the floor downwards during a walk causing an abnormal gait activity. The gait of the foot involves:• Foot catch on the floor on walking.• Patients lift leg high to avoid foot catching by tiptoeing the other way to equalize the sides.• While walking, the patient swirls the target leg to a side to avoid foot drag on the floor.In most cases, only one foot is affected but it may also cause issues with both sides at equal or different angles. Based on the severity, grades from 0 to 5 are categorized according to strength and movement of the muscles that lift the foot.CAUSES OF FOOT DROP Foot drop is due problems prone to a common peroneal nerve which is a tiny nerve that comes down off the sciatic nerve in the thigh. So any damage to this nerve or injury to lower back can serve as the causes for foot drop. It can also be prominent in muscle injuries or tumors.SYMPTOMS OF FOOT DROP• Movement of foot in a forward direction.• Affected Foot drags on the floor.• Foot pushes off and trails on the ground again.• An absence of dorsiflexion and plantarflexion of foot.• Leg bending at the knee on swing phase on climbing stairs.DIAGNOSIS OF FOOT DROP The diagnosis of foot drop can be done • By close monitoring of walking pattern• Identification of muscle weakness• Examination of functions of the nerves for damage or injury• X-Ray analysis for abnormality in soft tissue growth• Ultrasound to view cysts or tumors pressing the nerves• Computed Tomography to examine mass growths or functional modifications in the body.• Magnetic Resonance Imaging to identify lesions in soft tissues affecting the nerve pathways especially brain lesions.• EMG findings to monitor the electrical activity of the leg muscles.DATA ACQUISITIONThe neural activity of the muscles is recorded by means of Electromyography. This enables a close watch over the condition of the target muscles.the efferent neurons from the brain cause muscle contraction which gets recorded in the form of graphs or sounds or numerical values which can be later analyzed to assess the conditions. Data acquisition is done with the help of electrode which is inserted into the muscle through the skin. It picks up the electrical response which in turn gets viewed on a monitor whenever muscles contract. A nerve conduction study helps in arriving at the velocity of electrical impulses transmitted between any two neurons that in turn deduce the abnormalities concerning the muscles and their neural activity.ARDUINO: Arduino is an open source electronic platform or board that is coupled with a language and programming environment for creating logic on the chip. In this project Arduino Uno is used which is also an open source, both in its software and hardware specification so that hobbyists can assemble the simplest Arduino modules themselves by hand. In this model, it is allowed to communicate with lab view software installed in computer for further analysis of acquired signal.LAB VIEW SOFTWARE: Lab view (laboratory virtual instrument engineering workbench) is a graphical programming environment designed from national instrument to help engineers and code engineering systems. It makes use of data flow programming and graphical programming language. Lab view includes extensive support for interfacing to devices, data acquisition process etc. In this model, lab view is used to acquire the data from the Arduino board and analysis of signal is done.DATA ACQUISITION : Data acquisition is carried out by connecting all the hardware and software system involved in this project. The Power supply of two nine volt batteries is connected to EMG sensor and sensor’s signal pin is given to Arduino A0 pin and also sensor is connected to EMG electrodes. The Arduino board is connected to computer installed with lab view software for data analysis.MUSCLE SENSOR: Muscle sensor used in this model is advancer technology which measures electric potential of muscle cell which is called as Electromyography. The sensor converts the EMG signal into simple form of analog signal and is fed to microcontroller (Arduino). The cable is connected to sensor at one end and other end connected to EMG electrodes.DRIVER CIRCUIT: L293D is a quadruple high current half ‘H’ drivers which is designed to provide bidirectional drive current of upto 600ma at voltages from 4.5 to 36V. It acts as a current amplifiers since they take a low current control signal and provide a high current signal which is used to drive the two motors simultaneously, both in forward and reverse directions. Logic 01 and 10 will rotate it in clockwise and anti clock wise direction respectively.MODEL DESCRIPTION: This project model has three parts namely: Hardware part has Arduino controlled pedal with other circuits connected to it. Data acquisition is carried out by using EMG sensor connected to Arduino board and then to system with lab view software installed in it.Analysis is done using the results obtained from lab view software in excel sheets.WORKING: When the power supply is switched on, the voltage requried for operating the exerciser is obtained from 230V using two step down transformers. The power supply is first fed to driver circuit and then to Arduino board. The Arduino board is programmed with required program and delay (200ms) for exerciser to work in regular intervals. Then the patient with surface EMG electrode attached to region of peritoneal nerve is allowed to place their legs on the exerciser. Once the power is on, automatically the exerciser starts working. Then using EMG sensor, the EMG signal is obtained from analog pin(A0) of Arduino board which is fed to lab view software installed in the system. The signal obtained is finally analysed in excel sheet. This process is carried out to various patients and outputs are obtained and analysed.