Lihong Duan

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.

The Efficacy and Safety of the Combination of Total Glucosides of Peony and Leflunomide for the Treatment of Rheumatoid Arthritis: A Systemic Review and Meta-Analysis

Objective. To evaluate the efficacy and safety of the total glucosides of peony (TGP) and leflunomide (LEF) for the treatment of rheumatoid arthritis (RA). Methods. Randomized controlled trials (RCTs) on the efficacy and safety of the combination of TGP and LEF versus LEF alone for the treatment of RA were retrieved by searching PubMed, EMBASE, Cochrane Library, the China National Knowledge Infrastructure database, and Wanfang database. Results. Eight RCTs including 643 RA patients were included in the present meta-analysis. The quality of included studies was poor. The levels of ESR (P < 0.0001), CRP (P < 0.0001), and RF (P < 0.0001) in RA patients who received the combination of TGP and LEF were significantly lower than RA patients who received LEF therapy alone. The pooled results suggest that the combination of TGP and LEF caused less abnormal liver function than LEF alone (P = 0.02). No significant difference in the gastrointestinal discomfort was identified between the combination of TGP and LEF and LEF alone groups (P = 0.18). Conclusion. The combination of TGP and LEF in treatment of RA presented the characteristics of notably decreasing the levels of laboratory indexes and higher safety in terms of liver function. However, this conclusion should be further investigated based on a larger sample size.

Inertial Sensor-Based Motion Analysis of Lower Limbs for Rehabilitation Treatments

The hemiplegic rehabilitation state diagnosing performed by therapists can be biased due to their subjective experience, which may deteriorate the rehabilitation effect. In order to improve this situation, a quantitative evaluation is proposed. Though many motion analysis systems are available, they are too complicated for practical application by therapists. In this paper, a method for detecting the motion of human lower limbs including all degrees of freedom (DOFs) via the inertial sensors is proposed, which permits analyzing the patients motion ability. This method is applicable to arbitrary walking directions and tracks of persons under study, and its results are unbiased, as compared to therapist qualitative estimations. Using the simplified mathematical model of a human body, the rotation angles for each lower limb joint are calculated from the input signals acquired by the inertial sensors. Finally, the rotation angle versus joint displacement curves are constructed, and the estimated values of joint motion angle and motion ability are obtained. The experimental verification of the proposed motion detection and analysis method was performed, which proved that it can efficiently detect the differences between motion behaviors of disabled and healthy persons and provide a reliable quantitative evaluation of the rehabilitation state.The hemiplegic rehabilitation state diagnosing performed by therapists can be biased due to their subjective experience, which may deteriorate the rehabilitation effect. In order to improve this situation, a quantitative evaluation is proposed. Though many motion analysis systems are available, they are too complicated for practical application by therapists. In this paper, a method for detecting the motion of human lower limbs including all degrees of freedom (DOFs) via the inertial sensors is proposed, which permits analyzing the patients motion ability. This method is applicable to arbitrary walking directions and tracks of persons under study, and its results are unbiased, as compared to therapist qualitative estimations. Using the simplified mathematical model of a human body, the rotation angles for each lower limb joint are calculated from the input signals acquired by the inertial sensors. Finally, the rotation angle versus joint displacement curves are constructed, and the estimated values of joint motion angle and motion ability are obtained. The experimental verification of the proposed motion detection and analysis method was performed, which proved that it can efficiently detect the differences between motion behaviors of disabled and healthy persons and provide a reliable quantitative evaluation of the rehabilitation state.

Development of a novel ankle rehabilitation robot with three freedoms for ankle rehabilitation training

Ankle rehabilitation training takes an important role in the hemiplegic rehabilitation training. Traditional training requires the physical therapist treating the patient as one to one. The training process is repeating and needs a long period. The performances of training rely heavily on the skill of therapists. The training effectiveness depends on the skills of the therapist. To improve the training effectiveness, there are many ankle rehabilitation robots are proposed. However all of them are only focusing on providing a passive training to the patient. In this paper, an ankle rehabilitation robot with three degrees is proposed. This robot can not only realizes the passive training but also has much more sensors to detect the movements of the ankle, especially realizes the patient active training. In this paper, the detail design of the mechanism is introduced. The mechanical structure includes pedal parts, thigh fixing parts, cross slider parts, driving unit and sensing unit. Comparing with current ankle rehabilitation researches, this robot uses linear motion in horizontal and vertical plane instead of rotary motion to realize dorsiflexion/plantar flexion and abduction/adduction. Finally, we present ankle motion space analysis and ankle robot workspace analysis of ankle robot to verify the feasibility of the robot.

Development of a novel paediatric surgical assist robot for tissue manipulation in a narrow workspace

Paediatric congenital esophageal atresia surgery typically requires delicate and dexterous operations in a narrow and confined workspace. This study aims to develop a novel robot assisted surgical system to address these challenges.,The proposed surgical robot consists of two symmetrical slave arms with nine degree of freedoms each. Each slave arm uses a rigid-dexterous configuration and consists of a coarse positioning manipulator and a distal fine operation manipulator. A small Selective Compliance Assembly Robot Arm (SCARA) mechanism was designed to form the main component of the coarse positioning unit, ensuring to endure large forces along the vertical direction and meet the operational demands. The fine positioning manipulator applied the novel design using flexible shafts and universal joints to achieve delicate operations while possessing a high rigidity. The corresponding kinematics has been derived and then was validated by a co-simulation that was performed based on the combined use of Adams and MATLAB with considering the real robot mass information. Experimental evaluations for the tip positioning accuracy and the ring transfer tasks have been performed.,The simulation was performed to verify the correctness of the derived inverse kinematics and demonstrated the robot’s flexibility. The experimental results illustrated that the end-effector can achieve a positioning accuracy within 1.5 mm in a confined 30 × 30 × 30 mm workspace. The ring transfer task demonstrated that the surgical robot is capable of providing a solution for dexterous tissue intervention in a narrow workspace for paediatric surgery.,A novel and compact surgical assist robot is developed to support delicate operations by using the dexterous slave arm. The slave arm consists of a SCARA mechanism to avoid experiencing overload in the vertical direction and a tool manipulator driven by flexible shafts and universal joints to provide high dexterity for operating in a narrow workspace.

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.

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.

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.