Jian Qin

Development of a three freedoms ankle rehabilitation robot for ankle training

In recent years, rehabilitation robot has been a trend to replace traditional therapist rehabilitation on hemiplegic rehabilitation. Researchers have proposed many ankle rehabilitation robots on ankle rehabilitation training. However, most of them are only focusing on single freedom training or providing a passive training to the patient. In this paper, a novel ankle robot with 3 freedoms which combines the active training with passive training together is presented. To build the ankle physiological model, an experiment to detect the ankle physiological data is established. And based on the data, an ankle rehabilitation robot with three degrees is proposed. In order to detect the dynamic movements of the ankle, the robot embeds force sensors and motor encoders. Then, the detail design of the mechanism is introduced. There are pedal parts, thigh fixing parts, base, driving unit and sensing unit in mechanism. Each part of the ankle robot is introduced in detail. Comparing with the other ankle rehabilitation robots, this robot uses three blushless motors to direct three rotation motions directly, and the whole structure is simple and reliable.

Mechanism design and control strategies of an ankle robot for rehabilitation training

It has become a trend that ankle rehabilitation robots replace traditional therapist in rehabilitation field. Many ankle rehabilitation robots have been proposed for rehabilitation training by researchers. However, most of current researches are only focusing on providing the passive training. They not only ignore the active force training for patient, but also neglect the relationship between passive training and neurological rehabilitation. In this paper, an ankle robot combining active training and passive training, subjective awareness and objective training is proposed. The ankle physiological model and mechanism of ankle rehabilitation robot are described. The control strategies of advanced training modes, passive training and active training, subjective awareness and objective training are introduced. Finally, experiments are established to testify the mechanical performance of ankle robot. Furthermore, experiment of passive training and active training is held among healthy people and the result show a good stability of the control system.

Development of lower limb motion detection based on LPMS

Up to now, with the increasing of the elderly population, more and more patients are suffering from hemiplegia. It leads to a great need for hemiplegic rehabilitation. In traditional rehabilitation, each patient must be treated by therapist, one by one. However, since the individual differences of therapists, no effectiveness rehabilitation is guaranteed. And the rehabilitation status of patient is still diagnosed by therapists with their subjective experience. This would cause the inhomogeneity on rehabilitation evaluation and sometimes negative influence on the rehabilitation effect. To solve these problems, many research groups proposed rehabilitation evaluation systems to assess the status of the hemiplegic patients quantitatively. Rehabilitation motion detection is the basis of the evaluation system, and it requires the participation of therapist. However, many motion detection methods do not meet the detection requirements, such as mechanical tracking and optical sensor, etc. In this article we present a method to detect lower limb motion of hemiplegic patients based on inertial sensor technology. LPMS, a high performance, easy wearable, portable and large measurement range sensor, is selected as the motion sensor. We obtain the gesture quaternion of lower limb through LPMS, and then use the algorithm to convert quaternion to matrix and Euler angle. Combining with the simplified lower limb motion model, we compute the rotation angle of joint by processing the rotation quaternion in Matlab. Finally, the curve of rotation angle of knee is established. The method detecting the motion of lower limb can be integrated into the rehabilitation robot control system, realizing intelligent detection and evaluation. Thus, the rehabilitation robots could be expected adjusting training parameters based on patient status automatically, expected to have significant impacts in medical rehabilitation robot field.

Cytocompatibility of nano-hydroxyapatite/polyetheretherketone composite materials with Sprague Dawley rat osteoblasts

The growth and alkaline phosphatase (ALP) activities of Sprague Dawley(SD) rat osteoblasts cultured in the nano-hydroxyapatite/polyetheretherketone (n-HA/PEEK) composite extracts and on the surfaces of these composites were investigated in this study. The osteoblasts of 24-h-old SD rats were cultured by modified enzymatic digestion in vitro. The ALP activities of the SD osteoblasts cultured in n-HA/PEEK composite extracts were measured and the mineralisation was studied by alizarin red staining. The morphological characteristics of the SD osteoblasts incubated on the n-HA/PEEK composite surfaces were observed by scanning electron microscopy and the ALP activity was also detected. The results showed that the n-HA/PEEK composites have good cytocompatibility with the SD osteoblasts and there were no obvious differences between PEEK and n-HA/PEEK composites in ALP activities and mineralisation of the SD osteoblasts cultured in their extracts. N-HA/PEEK composites could promote the growth of the SD osteoblasts on the surfaces of them and the improvement was related to the content and uniform distribution of n-HA in the n-HA/PEEK composites. The 5 vol.% n-HA/PEEK composites was promising to be used for bone substitute materials.

Studies on antibacterial activities against S. aureus of chitosan metal chelates prepared in magnetic field.

In order to study the antibacterial activity of chitosan metal chelates prepared in magnetic effect, the antibacterial activities of these chelates on Staphylococcus aureus were investigated by the agar diffusion paper method. The minimum inhibition concentrations of chitosan-metal chelates were measured. With different degrees of substitution, the inhibition efficiency of the chitosan-metal chelates is different. The inhibition of chitosan on S. aureus increased with the chitosan concentration. Among the chitosan-metal chelates, the inhibition efficiency of CS-Cr is the best. The inhibition efficiency of chitosan-metal chelates prepared in the magnetic field of 400 kA/m on S. aureus is higher than the inhibition efficiency of chitosan-metal chelates prepared without the magnetic field enhanced. The minimum inhibitory concentrations are, respectively, as CS-Cu: 12.5 mg/mL, CS-Pb: 6.25 mg/mL, CS-Cr: 3.125 mg/mL. It is well known from the results that chitosan-metal chelates maybe applied in antibacterial process.

Development of a novel finger and wrist rehabilitation robot for finger and wrist training

Up to now, with the developments of society, aging problems are more serious. With the requirements of rehabilitation, a large of hemiplegia rehabilitation devices are launched out. But most of the hand training robots just limit to the fingers flexible training. They ignored the importance of functional training of hand, and ignore wrist cooperative training in the rehabilitation process. In this paper, a novel finger and wrist rehabilitation robot will be introduced for hemiplegia rehabilitation, a creative hand rehabilitation way is presented. Two rehabilitation units are included -wrist rehabilitation unit and hand rehabilitation unit. Novel torque sensor units with a simple structure are designed to detect torque. The detail of the sensor is introduced in the paper. The proposed finger and wrist rehabilitation robot leads to further research on the rehabilitation robot.

Effect of preparation process on tensile strength of nano-hydroxyapatite/polyetheretherketone composite materials

Tensile strength of nano-hydroxyapatite/polyetheretherketone(n-HA/PEEK) composites with 5vol.% HA prepared by various process were researched in this study. The untreated n-HA/PEEK composite specimens with HA content of 5 vol.% were prepared via a compounding and injection molding process at first. Partial specimens were annealed in the oven at 250°C for 1h. Then silane coupling agent (SCA) was employed to modify the HA nanoparticles and SCA-HA/PEEK composites were prepared with injection molding process. The n-HA/PEEK composites were prepared by using repeated melting, crystallization and granulation at last. The tensile strength of all the HA/PEEK composites were measured by an Instron IX Material Testing System and the fracture surface of nanocomposites were examined by scanning electron microscopy (SEM). The results showed that heat treatment, SCA modification, repeated processing could improve the tensile strength. The optimal tensile strength of the composite materials were prepared by repeated processing.

Development of a human-like motor nerve model to simulate the diseases effects on muscle tension for neurologic examination training

Neurologic examination takes an important role in the physical examination. By now, several methods have been carried out for medical training which bring the benefits for trainee to master the skills and accumulate experiences. However, because of the limits of these methods, the training effectiveness is limited. With the developments of technology, more and more simulators have been launched to improve medical training effectiveness. However, most of these simulators only focus on mimicking the symptoms, not simulating the pathology of diseases. In this paper, we propose an improved motor nerve model which is used in the elbow robot named WKE-2(Waseda Kyotokagaku Elbow Robot No.2). This robot is designed to simulate the disorders of motor nerves to give the trainee a full training on the elbow examination. The motor nerve model mimics the real motor nerve structure. And the functions of each part are designed from analysis of the real functions of each organ. In this robot, the effects of motor nerve system, and various symptoms related to the examination of elbow force, biceps tendon reflex, involuntary action are simulated. Making use of this robot, a systematic training on the skills as well as the understanding of knowledge is provided. Finally, several experiments are performed to verify our proposed system. The experimental results lead to the consideration that the approach is worth following in further research.

Mechanism design of an ankle robot MKA-III for rehabilitation training

With the development of aging society, the number of hemiplegia patients grows rapidly and over 75% of survivors suffering hemiplegia need rehabilitation training. To assist therapists, series of rehabilitation training robots were carried out. However, most of current researches are only focusing on function training. They ignore the importance of neurological rehabilitation in early phrase of hemiplegia. Early rehabilitation takes a fundamental position in neurological rehabilitation and whole-body rehabilitation. To fulfill all of those requirements, MKA series have been developed. During the experiment, there is some problems including unreliable transmission and dehumanization design. For these reasons, in this paper, we propose the MKA-III. Based on physiological structure and rehabilitation theory, the mechanism was design. In this paper, the detail design of the mechanism is introduced. The mechanical structure includes four parts, adduction/abduction parts, dorsiflexion/plantar flexion parts, inversion/eversion parts and sensing unit. Each part of ankle rehabilitation robot was introduced in detail. In addition, for the motor control and information acquisition, the hard system is introduced.

Gait motion analysis based on WB-4 sensor with quaternion algorithm

Up to now, with the increasing of the elderly population, more and more patients are suffering from hemiplegia. The needs for hemiplegic rehabilitation is increasing quickly. As traditional rehabilitation, each patient must be treated by therapist, one by one. However, because of the different levels of therapists, the rehabilitation cannot be performed as the as the same. Normally, the rehabilitation status diagnosing is still be performed by therapists with the subjective experience. It caused the inhomogeneity on rehabilitation evaluation. It also sometimes causes negative influence on the rehabilitation effect. To solve these problems, many researches focusing on assessing the status of the hemiplegic patients quantitatively are proposed rehabilitation evaluation systems. Rehabilitation motion detection is the basis of the evaluation system, and it requires the participation of therapist. In this paper, a method is presented to detect lower limb motion of hemiplegic patients based on inertial sensor technology. The gesture quaternion of lower limb can be obtained through LPMS. With the matrix and Euler angle changing algorithm, combining with the simplified lower limb motion model, the rotation angle of joint can be computed. Finally, the curve of rotation angle of knee is established.