In this paper, the operational support system using 3 DOF joystick is proposed for transfer system on a plane. The 3 DOF joystick enables operator to operate the transfer machine with forth and back, right and left, and rotation motion. And, it has motors for presenting the reaction force on each axis. The motors are controlled by the proposed reaction force control system. The reaction force control system consists of PD control with proportional and devivative gains varying with the distance between the transfer object and the obstacle. The effectiveness of the proposed operational support system is verified by the simulator of the transfer machine on a plane.
The video surveillance system is used in a manufacturing industry etc. Conventional video surveillance system can detect abnormal motion from only image. However, it is difficult to detect abnormal situation from only images automatically. Therefore, we propose a warning alarm system using image and some sensors. We adopted higher order local autocorrelation (HLAC) features from image data and some censor data.
In this paper, a power assisted attitude control system composed by parallel wire is proposed. This system achieves to control attitudes of an object reducing operator's load and realizing direct manipulation. In our previous researches, a power assisted control system for an overhead crane was proposed. Operators could move a heavy object freely by slight force horizontally, vertically and 1-DOF attitude. However, it's had a restriction in the shape. Our new proposed equipment consists of the over-head crane and 2 linear cylinders. The power assisted 2-DOF attitude control algorithm to control the lengths of the cylinders and the hoisting motion of the crane synchronously is proposed, and the effectiveness is demonstrated by the simulation. Finally, an advantage of the proposed controller is demonstrated by the experiment.
In order to robotize bead grinding tasks, we have developed an active tool holder which adjusts the tool position independently of robot motion. A simple stillness control using force sensor is applied to the active tool holder. The control system is effective for flattening the small unevenness of the weld bead. However, it is difficult to remove large bumps of the weld bead by the control system. To solve the problem, we propose a method to reduce the feed rate of a tool at the large bump.
This paper deals with a method to design the control architecture for cooperative behavior of multiple autonomous mobile robots using an extended Petri net based approach. Centralized planning with hierarchical net models has been adopted to be easily implemented in Petri net formalism. A multi-robot task net model can be defined as the union of several single-robot net models enriched with synchronization constraints between actions of different robots. The synchronization constraints are used to add temporal constraints in the execution of the actions in a multi-robot task, such as sequential execution and simultaneous execution of two actions by two robots. Given a multi-robot task net model, the single-robot net models can be automatically derived by replacing synchronization constraints with communication actions and can be executed in an autonomous decentralized manner, where all the conflicts in the actions of different robots are resolved without the need of a central coordinator.
The purpose of this study is to develop the high speed checkweigher with electromagnetic force balance system. We approximate the checkweigher by a spring-mass-damper systems as the physical model, and the equations of motion are derived. The validity of the proposed model can be confirmed by comparison of the simulation results with the realistic responses. The proposed model offers practical and useful information to examine control scheme.
Robot are expect to be new tools for the operations and observations in the extreme environments where human has difficulties for accessing directly, deep ocean, space, nuclear plants and so on. One of the important matters to realize mobile robots for extreme environments are to establish systems in the movement and their structures which are strong enough to disturbance. A solution for realization an adaptive control system is to learn and imitate biological systems. For example, in the spinal cord of animals, neural oscillator systems called Central Pattern Generator (CPG) are proven to exist and investigated that CPG control rhythmical signals such as swimming pattern, walking locomotion, heart beats, etc. In this paper, an adaptive control system based on the entrainment feature of neural oscillators was developed and applied to motion control of a snake-like robot.
Robot that uses body-propulsion like the snake can moves in the weak grounds and bad environments. We focused the movement method imitated sidewinding that the snake living in desert, used to move across loose or slippery grounds. The track of the movement of the unit in the cross section that is parallel to movement direction when sidewinding, becomes like elliptic cylinder. The motion of sidewinding can be described as rolling of cylinder. Using this theory, we suggested the method of analyze the track of the snake robot movement, and measured the movement distance in experimentation. As a result, theoretical values agreed well with actual measurements. This theoretical calculation can increase its accuracy by considering the effect of slipping and inertia.
In this paper, we have described a miniaturization of a flying microrobot. This robot has two flapping wings including magnets and can be driven by alternating magnetic fields. In order to downsize the robot, the effect of the magnet size and wing area on thrust has been examined. In addition, the relation between the spring constant of the torsion spring and thrust has been experimentally investigated.
A real-time simulation assisted gait modification approach for a pole climbing robot snake was developed to minimize gait and implementation errors. A preliminary parameterized gait was improved by adjustments based on the expected distance, in order to ensure contact with the pole was properly maintained. A real-time simulation with high physical accuracy was used to provide the distance information.
We measured differential pressures on the wing of an ornithopter with different stiffness of veins in flapping motion. The pressure measurement was carried out by using a MEMS differential pressure sensor attached on the wing surface. The ornithopter was modeled after a hawkmoth. The wing length was 110 mm, and total mass was 7.3-7.7 g. We fabricated three types of wings which had veins of different cross-section. In the experiment, the ornithopter was propelled by an electric motor and flapped at 10-11 Hz. The result suggested that when a wing is flexible, the different pressure on the wing is small, but the passive deformation of the wing is large during takeoff, then the ornithopter can fly by being subjected to thrust during upstroke and lift during downstroke.
The authors have been investigated how to use protists as living micromachines by controlling their behavior using their taxis. Daphnia magna has strong positive phototaxis to the blue light. Therefore, we can control Daphnia's behavior very well by lighting blue light to the aiming angle. In our previous study, we succeeded to make an automatic object manipulation system by using motion controlled Daphnia. We have to prepare special tools for microorganisms to use microorganism that microorganism itself can never do. Daphnia has fairly large body (body length: 3mm) and exoskeleton that enables to glue special tools on Daphnia. Therefore, we could succeed in the previous study to destroy a balloon by a needle installed Daphnia and to make medical injection by using special injector. These tasks, however, were done at just under the water surface and the positions of the height were fixed because we used a wing float to stabilize Daphnia's swimming. Therefore, in this study, we tried to make Daphnia do special works into the water freely. We attached a polypropylene needle on the Daphnia's back as roles of float and special tool. The Daphnia's swimming speed was increased by attaching the needle. We also made a motion control pool in the vertical plane. We could automatically control Daphnia along star-shaped target route on the vertical plane.
In this paper, we proposed large motion control pools of paramecium by applying electrical field. To prevent the pH change in the experimental area, the culture media in the electrodes area of the pool is exchangeable by the micro tube pump. The experimental area and the electrodes area are separated by the membrane filter to keep electrical conductivity and to prevent the going in and out of the culture media. By this design, we can set the electrodes distance as 11mm. We made two types of the pool. One is fixed eight electrodes (four pairs of the counter electrodes) type that is the same as our former studies. The other is the electrodes rotatable type to improve the resolution of the electrical field application angle. This type pool has four electrodes (two pairs of the counter electrodes). A servo motor is used to rotate the electrodes. By using these pools and improved motion control algorism, the controllability of the paramecium was much improved. In the case of the electrodes rotation pool, the average control deviation was 0.149mm.
In this paper, we investigated to drive a seesaw by position controlled downward flow of the Euglena's bioconvection. The position of the downward flow was controlled by applying Euglena's phototaxis to the scanning blue laser beam. Formally, we succeeded to drive a seesaw by electrically position controlled downward flow of the Tetrahymena's bioconvection. In this paper, we aimed to reproduce the laser control version of this seesaw driving by using Euglena. We have already confirmed that if the experiment is done in the horizontal planar pool, we could make any shapes of Euglena group and we could also assemble simple mechanical parts by pushing the part by Euglena group. In this study, we first investigated the basic conditions to control the bioconvective downward flow by irradiating the scanning blue laser. The results, however, showed that to generate and to control a steady bioconvective downward flow was very difficult due to the Euglena's poor swimming performance. We reduced the friction of the seesaw and introduce the arc shaped scanning to guide the Euglena located at around the pool side into the bioconvective flow. By using this scheme, we could drive the seesaw up to one reciprocating motion.
We have been developing motor-tendon-joint series connection type biomimetic soft actuators to make robots act jumping, running and dancing like animals. We proposed and have been developing the silicone rubber tendon structure for the robot to model the muscular-skeletal system of the animal, and act like tendons of animals. In the previous paper, we succeeded to decrease vibration by introducing the blend control method of a feedback control and a feedforward control. In this study, aiming to reduce the vibration, we reconstructed the actuator to add the vibration reduction motor. The jumping experimental results showed that this actuator can reuse the elastic strain energy of the silicone rubber stored by the landing shock as a jumping kinetic energy. The jumping height becomes larger as a order of 1: continuous jumping (largest), 2: jumping from bending and stretching reaction, 3: jumping from full bending posture (smallest). The jumping height of the actuator with the vibration reduction motor, however, is lower than the simple one motor actuator. We also made a self-standing type test bench.
This paper analyses the group behavior of soldier crab. In particular, we adopt method of animal-robot interaction and analyses based on fluctuation index. In the experiment, the mobile object interacts with sixteen soldier crabs. From experiment analyses, it was found that collective behavior of crabs has scale free. And this behavior is not affected by the mobile object.
We have developed oscillation wing propulsion type fish robots which were modeled tuna. In this paper, we first reconstructed a Scotch-York type driving mechanism of the caudal fin. In the new driving mechanism, a 2.6kW outrunner type sensor-less brushless motor was replaced to a 5kW motor and the overall reduction ratio was reduced from 45.38 to 24.75. This new driving mechanism was tested by hanging under a surf board as a test bench. The results showed that this driving mechanism worked very well. The results, however, also showed that too much increased thrust force of the caudal fin made the large amount of the nose lifting of the surf board. It means that we could no longer examine by this test bench. So we decided to make the robot body first. We decided to make a robot body by dividing into three parts, head, body part and tail. The head can move by the synchronized motion of the tail by the different small ratio. This movable head enables the robot body made the few rigid parts mimicking the motion of the real tuna. The dorsal fin and the anal fin were set the fulcrum of the tail oscillation like tuna to reduce the transverse movement of the fulcrum. The body was made of ABS resin using 3D printer. The overall length is 1850mm. The experimental results will be reported at the conference.
Instead of human, to investigate the aquatic environment, we are continuing research and development on small aquatic robots with SMA actuator. We mount the system that mimics the physical structure of the fish for high efficiency of robot. In this research, to improve the problem of conventional fin, I made new fin structure that arranges two elastic plates with fixed SMA on only one side vertically and evaluate it. Degradation of SMA has improved to some extent, however, compared with the conventional structure, in addition to the reduction in speed, it decreases in roll stability. So we require more improvement of fin.
Many aqua robots are in practical use to investigate various aquatic animals. Caudal-fin-driven robotic fish that imitate live fish do not alarm other underwater creatures. Moreover, because such robotic fish do not use a screw propeller, they are unlikely to be entangled with water plants. In this study, two caudal-fin-driven robotic fish have been constructed with a DC brushless motor to speed up. The propulsive performance of the one-joint robotic fish and the two-joint robotic fish was investigated using several caudal fins. Two-joint robotic fish had a good performance of propulsive force 330 mN and swimming velocity 400 mm/s at the phase difference 60 degree. This robot was able to swim like live fish.
Though maxillofacial palpation is one of the essential diagnosis skills for dentists, students of dental school have no experiences of undergoing maxillofacial palpation against ambulant patients before their graduation due to the concerns about risks to the patients. Hence, a virtual training environment of maxillofacial palpation has been desired from the coauthor dentists. Then this study aims to develop a virtual patient model of a maxillofacial palpation system that is composed of a virtual patient model and a haptic interface. A virtual patient model was firstly built by using CT data of head mannequin and linear finite element method. This paper introduces the virtual patient model and discusses about the future development of this system.
This paper describes the development of an endoscopic device veering-out the latex tube with jamming of granular materials. Colorectal cancers can be cured completely if they are discovered early with a large intestine endoscope. While the endoscope can be used to screen and heal this cancer, its operation is difficult. Peculiarly difficult operation is to pull up a sigmoid colon. In this study, to solve the difficulty associated with the use of this endoscope, we consider that an endoscope is passed through a sigmoid colon by simply pressing without the need to pull up the sigmoid colon. Therefore we propose an endoscopic device veering-out the latex tube with jamming of granular materials. First this device can automatically set flexible tube in a sigmoid colon by veering-out the tube and metamorphose hardness of the tube by jamming of granular materials. Secondly endoscope is easy passed through in the hard tube by only pushing. In this paper, we executed stiffness experiment to select jamming granular. Moreover we perform driving test of veering-out the latex tube to establish whether the method can automatically set flexible tube in a sigmoid colon.
In this study, we develop a power assist suit adapted to bi-articular muscles model. Before now we have already developed the leg mechanism of power assist suit adapted to bi-articular muscles model using parallel links. The leg mechanism of power assist suit adapted to bi-articular muscles model has high torque and safety from a series of experimental results. Therefore, we improve Power Assist Suit based on conventional leg mechanism confirmed the good efficiency. Furthermore the new model is able to hold 10kgf weight as a result of mechanical improvement. In addition, we consider distinction method by Neural network with electromyography control.
During stomach radiography, the abdomen of a patient is pressured to take X-ray photographs of the stomach clearly. Pressing the abdomen makes barium in the stomach spread, so the clear image of the fold and lesion can be obtained. However, it is difficult to compress effectively, and the examination time become longer. The purpose of this research is the realization of the effective compression of abdomen in stomach radiography. The moving mechanism which consists of three layer rubber tube can move the pressure mechanism by using air pressure. This mechanism realizes fine tuning to the compression position of abdomen. These device and mechanism reduce the examination time and the burden to the patient. From thee evaluation experiments of the moving mechanism, it is showed that the moving mechanism propels the pressure bag well when 118N load is given to the pressure bag.
We have developed a bed-type non-invasive ultrasound theragnostic system (NIUTS) that tracks and follows the movement of an affected area (kidney stone/tumor, in this study) by irradiating it with high-intensity focused ultrasound (HIFU). In this paper, we propose a mechanism to control the position and orientation of the ultrasound probes aiming at enhancing the servoing performance of the affected area. Proper positions and orientations are required to acquire the proper ultrasound diagnostic images.
We have been studying the technologizing and digitizing skills of the medical professionals in the medical theragnostics. The concept of the technologizing and digitizing skills is to extract functions in medical professional skills, reconstruct and implement these extracted functions in the mechanisms/controllers/image processing algorithms of the medical support system. In the present paper, we propose a redundant motion control mechanism in accordance with theragnostic functions for a non-invasive ultrasound theragnostic system (NIUTS).
This study consists of the development of soft finger with a function of attaching and holding internal organs by using fluid power. It is necessary to attach and hold many kinds of organ softy. Inspired in an octopus, stable adhesive force is produced through application of negative pressure in the sealed space by the object. The suckers have roundly shape for attaching softly and urethane funnels for attaching various kinds of organs. It is verified through experiments that soft finger is effective in the laparoscopic surgery.
In medical field, medical equipment which was used by a surgery such as drug containers and surgical instruments are recorded to the chit respectively or counted repeatedly by the manual labor of medical staff. The purpose of these operations to the medical equipments includes preventing surgical instrument from remaining in the body, and requesting insurance in medicine instruments such as medicine or medical supplies. However, many kinds of surgical instruments and medical supplies are used in one surgery, and resemble each in shape. In addition, medicine instruments need to be assorted according to if insurance can be requested. Thus, the following problem exists: causes human error such as error in writing or forgetting to write, and burdens health professions. To deal with these problems, the equipment processing system not to go through the hand of the person is ideal, and to realize this, to distinguish and manage equipment automatically is necessary.
Microchannel fabricated using MEMS technology have developed and contributed to the area of chemistry, biology and medical procedure. We think that three-dimensional (3D) microchannel with circular cross-section can contribute to development of these areas. In this research, our purpose is fabrication of the 3D microchannel with circular cross-section for simulation of capillary vessels. To fabricate the 3D microchannel with circular cross-section, we employ 3D exposure method using femtosecond laser and mask hybrid exposure (FMEx). FMEx makes it possible to fabricate a millimeter-sized large structure with submicrometer resolution in three dimensions and achieves easy injection of solution because it is possible to fabricate typical microchannel used for the inlet or outlet port of the model at a short time. In this paper, we fabricated 3D microchannel whose diameters are approximately 5.6 μm for replication of capillary vessels.
In recent years, Kinesitherapy is beginning to be recommended to care for depressive patients since a cerebral blood flow is improved. And bicycle exercises which is easy control of exercise intensity, are focused. Depressive patients are very sensitive to a comparison with another person, they must not compete. In this paper, we propose new bicycles controlled constant speed in order to avoid competition and develop two prototype models.
We developed a micro-whistle-type sensor driven by pneumatic pressure for the measurement of the applying force at the tip of a forceps in endoscopic surgery. The displacement applied to the sensor can be detected by the change of the resonant frequency of the whistle, which is controllable by the length of a resonant tube. It was fabricated using surface micromachining, resulting in the advantages: small size enough to be integrated into a forceps and capability of mass production. The standard deviation of the resonant frequency was 1.8 Hz and the magnitude of the sound was 83 dB. We obtained the proportional relationship between the length of the tube and the resonant frequency. Although these properties are comparable to our previous whistle-type sensor fabricated by a NC machine tool, it is proven that the MEMS based fabrication can produce a number of equal quality sensors.
The purpose of this research is research and development aiming at the problem solving of a used injection detecting device. The medical worker's burden decreased by introducing the device. However, on the other hand, there are some problems that a medical worker does not have a method of getting to know when detection finished or a medical worker have a hard time returning to device only for checking when the distance of the medical worker disconnected from equipment is too far. By solving these problems, a medical worker can reduce the time to use for a check, and allot the vacant time for other works. As a result, the medical institution can realize better medical service, and an improvement of efficiency. Therefore, the remote management application software in this research is developed aiming to solving the problem of a used injection detecting device.
This paper reports strength change of a voluntary contraction when the voluntary motion is synchronized with a stretch reflex induced by involuntary stretch of a muscle. A device developed in this study introduces the stretch reflex on flexor muscles of MP joints by instantaneous extension of the MP joints of four fingers. The device also measure flexion torque of the MP joints and a bioelectric potential (BEP) signal around a forearm. First, it is confirmed by experiments that the reflective force of the stretch reflex becomes bigger when an angular velocity for the instantaneous extension of the MP joints increases. Second, it is found that the contraction force of voluntary flexion is intensified by the stretch reflex synchronization. These results will back up a mechanism of the repetitive facilitation exercise (RFE) that is patient's repetitive exercises of an intended movement accompanied with a facilitation given by a therapist.
We have developed a hand exoskeleton mechanism composed by three layered spring blades and presented in our earlier publications. The advantages of the proposed mechanism compared to other devices are compact, light weight and high adaptability to the environment thanks to the compliant structure. In this paper, we present the improved mechanism for further simplicity. The improved mechanism design, prototype implementation and evaluation are described.
The purpose of Big-hand is to realize supporting for standing-up motion by air pressure actuators. Big-hand holds a human body and an active deformable balloon lifts a human body. By using air pressure actuators, this device can be smaller and lighter than conventional transferring support devices and more easy to use. Elderly population in Japan is increasing rapidly in recent years. However, the number of carers is a chronic shortage and a burden of carers is considerable. Especially, transferring support demands carers of much labor. So this device is expected to reduce time and labor of nursing and to improve nursing environment.
People can live a comfortable life thanks to the human balancing control capability. This capability is classified into two types, static and dynamical. About the static capability, some evaluations and training methods have been established. On the other hand, an effective training and evaluation method has not been found for the dynamical capability. Therefore, we built equipment that has some dynamical training patterns. One of the training patterns of our device is similar to that of the "Rola-Bola", and other balance boards used for street performance or athletic training. In this study, we compared the training effect of the "Rola-Bola" with our device to assess superiority of evaluation and training. As a result, it was revealed that a ride became relatively difficult when someone used the device after a ride on the "Rola-Bola".
Several exoskeleton robots are developed for a rehabilitation. These robots assist the user to execute the transitive motion rehabilitation by a power assist. Therefore, we propose a new robotics system which execute a automatic movement rehabilitation by target motion instruction. This proposal robot is a wearable and flexible body like clothes, and actuated using the wire-driven mechanism. This robotics system decides the desired posture based on the operator's posture, and calculates the each corrected joint torque. Since this robot executes the force display using wire driven, the tensional force is calculated by a quadratic programming. We quantitatively evaluated the mechanical contribution of the proposal method using computer simulations. From the simulation results, we expect the effectiveness of an occupational therapy and a physical therapy, and this robot can assist the operator to induct the advanced skillful motions.
The falling of the elderly person is a serious social problem. The decline of the balance ability is one of the big factors of the fall. The development of the balance ability training system is of aim of this study. In order to improve the effect of training, we suggest a balance training system specialized in somatic sensation by intercepting human subject's sight. This paper presents an investigation about superiority of the sight interception training. Specifically, eye-open training and sight interception training are compared by the foot pressure center trace before and after the training. As a result, the sight interception training was significantly shown to be effective. This result will be applied to the development of the balance ability training system.
The final aim of our study is to construct the quantitative evaluation system of sensorimotor integration function of a hand during grip motion. Quantitative evaluation is demanded on rehabilitation facilities for early recovery. Sensorimotor integration function of a hand is necessary when a patient grips objects. We had designed the quantitative evaluation system of sensorimotor integration function during grip motion by using a flexible object. The evaluation system has two characteristics of "deformation-voltage" and "deformation-force". In this paper, we design and verify a new grip device to solve two problems in the conventional device. Firstly, the difficulty of grip in the conventional device was high, because the conventional device had complicated characteristic. Secondly, the spring characteristic of grip device cannot be changed easily. The result of verification shows that two technical problems in the new device are solved.
For reducing a risk of pressure sore caused by long period sitting on a wheelchair, a patient is required to depressurize buttocks by changing the posture suitably. Thus, we have been developed an automatic depressurization motion assistance system for a seated patient on a wheelchair. In our previous work, we developed a sitting surface coordination system which can lift or incline and assists a depressurization motion of a patient. However, in some cases, it is difficult to change his posture suitably for patients who do not have enough physical strength in their upper body using our proposed device. Therefore, in this paper, we propose a novel posture coordination assistance system for a wheelchair user. Our system consists of the adjustable sitting surface and novel proposed adjustable backrest. These two devices coordinate the sitting posture of the patient automatically. The performance of our system is verified by experiments using our prototype.
The final aim of this research is to develop a quantitative evaluation system of shoulder joint function using the three-dimensional force display robot. In this paper, we carried out two experiments to develop quantitative evaluation methods of shoulder joint function. In the first experiment, we analyzed therapist's motions during the shoulder joint function tests. As a result, we proposed estimation algorithm of the rotational angle and the velocity of upper limb from the subject's force during the tests. And we verified the effectiveness of the algorithm. In the second experiment, we measured subject's forces during the tests. As a result, we confirmed that glenohumeral joint laxity is correlated with the ratios of the right to the left subject's force in the initial position during abduction, external rotation, and horizontal abduction motion. Moreover we developed the cooperativeness evaluation methods on the basis of the skillful therapist's testing motions.
In the authors' earlier publication, a hand exoskelton device using layered spring blades has been presented. The advantages of the presented mechanism compared to other devices are compact, lightweight and high adaptability to the environment thanks to the compliant structure. In this paper, as a further extension of the presented mechanism, we propose a motor-less hand exoskelton device with a motion translation capability from the wrist exion and extension to the grasping.
In recent years, the population that requires assistance with walking has increased owing to a decrease in leg muscular power with age. To prevent muscle weakness and expand their sphere of activities, we develop the orthosis for walking assistance using a pneumatic artificial muscle to assist leg muscular power. In order to judge the availability of the orthosis, we measure the effect on assistance quantitatively. EMG and step length are measured with assistance on healthy subject. We observed that the EMG of the sartorius muscle, which helps swing the leg forward, decreased. And step length is increased as a result of assistance. I think these results mean that a person with little muscular strength can walk like a healthy person.
Optical motion capture systems, which are used in broad fields of research, are costly; they need large installation space and calibrations. We find difficulty in applying it in typical homes and care centers. Therefore we propose to use low cost contact force measurement systems to develop rehabilitation and healthcare monitoring tools. Here, we propose a novel algorithm for motion recognition using the feature vector from force data solely obtained during a daily exercise program. We recognized 7 types of movement of 2 candidates. The results show that the recognition rate of each motion has high score. The results also confirm that there is a clustering of each movement in personal exercise data, and a similarity of the clustering even for different candidates thus that motion recognition is possible using contact force data.
Surface-Electromyograms (sEMG) are directly correlated to the contraction of muscle and they are used as a index of occurrence of muscle tension in sports or rehabilitation. However sEMG is affected with individual features or experiment condition, so it is difficult to compare sEMG directly. The purpose of this research is to propose a method to estimate the active joint torque with related muscle's sEMG. The joint torque can be used as an index of training effect, to control prosthetics or power-assist systems. We measured sEMG of 4 muscles of subjects while moving the elbow joint with variable load. We propose polynomial non-linear model the relationship between sEMG and joint torque and predict the joint torque with the model.
The objective of this study is to develop a cellular delivery method of biomolecules based on electrokinetic forces. We used a glass needle containing YFP plasmid DNA for studying cells after cellular delivery. Observation of expansion of a HeLa cell during cellular delivery revealed that the direction of electrokinetic flow was dominated by electrophoresis. Penetration of a cell was also detected by measuring an ion current through the needle. Incubation of cells in minimum essential medium was necessary for maintaining long-term cellular activity. Expression of YFP was observed in cells without penetration because of diffusion of the DNA in a solution.
A patterning technique of cells is required for studying cell communication between multiple cells. The objective of this research is to develop a versatile cell manipulation station enabling pattern of single cells with high precision and in super parallel format. In this paper we developed a cell feeder to collect cells on microprobes and decrease manipulation force depending on the suction pressure. Electrodes of the cell feeder were etched from ITO substrates by MEMS fabrication processes. Application of alternate voltage of 5, 10, 15, 20_<Vpp> collected cells by dielectrophoresis. Cells were collected between the electrodes at 5 MHz by positive dielectrophoresis. For efficient cell capture, we combined an array of microprobes and a cell feeder and manipulated cells.
We developed a highly-functional untethered on-chip robot for cell handling and micro-knife made by Si to cut zona pellucida of oocyte. The on-chip robot has a gripping mechanism which can grasp a cell or micro-object with sufficient power. The position and handling force of the robot are controlled independently by the magnetic force. The permanent magnets and electrical magnet are assembled together, and they are put under the microfluidic chip. The micro-knife had made by grayscale lithography technique. We demonstrated a cutting of zona pellucida and pushing out a part of cytoplasm of bovine oocyte.
The purpose of this study was the fabrication of Bioactuator using transgenic somatic muscle and the evaluation of the light response characteristics of the Bioactuator. Transgenic somatic (body-wall) muscle of the larva of Drosophila Melanogaster fruit fly was used as a Bioactuator. In this report, we first made photosensitive somatic muscle, which express channelrhodopshin-2 (ChR2) with gene manipulation. Then, we made a comparative review of some methods of utilizing the ChR2 expressing somatic muscle as a Bioactuator to generate contractile force in the one-dimensional direction. Finally, we confirmed the step response of the Bioactuator to optical stimulation in order to evaluate its basic characteristics.
In this report, a method to measure cytoplasmic viscosity using a nano machine was proposed. We fabricated magnetically driven nano machine by spattering nickel on the suface of carbon nano coil. The nano machine was introduced into the epidermal cell of commelina communis using microinjection. We calculated cytoplasmic viscosity by measuring the magnetic flux density of the nano machine when losing steps. As the magnetic field gets weaker, the nano machine eventually loses its steps. The relationship between the viscosity and the magnetic flux density applied to the nano machine when losing steps is given by η=kB^2, where k is the coefficient for each nano machine. Based on this theory we measured the cytoplasmic viscosity of commelina communis and obtained the viscosity of 1.1±0.2 mPa・s.
In this paper, a method is proposed to fabricate arbitral shape hydro-gel microstructure by hydrophilic and hydrophobic surface. The micro-structure is extended from 2D to 3D structure by micro-manipulation technique. By the proposed method, we aim to fabricate arbitral 2D/3D cell structure by embedding biological cells in to the hydro-gel.