[Implementation of control system and software design for limbs rehabilitation training based on PCI-1240].

This article presents the design of a motion control system for seated lower-limb rehabilitation training. The system is composed of lower limb exoskeleton, motor drive circuit, program of motion control, and so forth. The power of lower limbs joints is provided by six motors. The PCI-1240 motion control card is used as the core. This study achieved repetitive rotation training and gait trajectory training of lower limbs joints, of which the velocity, angle and time can be accurately controlled and adjusted. The experimental results showed that the motion control system can meet the requirement of repetitive rehabilitation training for patients with lower limb dysfunction. This article provides a new method to the research of motion control system in rehabilitation training, which can promote industrial automation technique to be used for health care, and conducive to the further study of the rehabilitation robot.

[Design of Balance Function Telerehabilitation System Based on C/S].

This article shows a new design of telerehabilitation system for balance function assessment and training in our laboratory. The system is based on C/S network architecture, and realizes the telecommunication through socket network communication technology. It implements the teletransmission of training data and assessment report of sit-down and stand-up, online communication between doctors and patients, and doctors'management of patient information. This system realizes remote evaluation and telerehabilitation of patients, and brings great convenience for the patients.

[Dynamic modeling and simulating of squatting-standing action of human body].

It is very difficult for stroke patients to complete the action of squatting-standing because their equilibrium function ability has been seriously declined. It was necessary, therefore, to do a deep research on the action of human squatting-standing and to set up an accurate model and simulation. In our modeling research, the movements of upper limbs and head was neglected, and a seven-segment model was developed to establish the coordinate system of human squatting-standing action. It calculated the knee joint moment and hip joint moment during squatting and standing by utilizing Lagrange method, and then simulated this mathematical model by utilizing Matlab. Geometric model of human squatting-standing was developed and simulated in ADAMS which proved that the established Lagrange model was reasonable. It would also provide significant theoretical references for further study and development of squatting-standing rehabilitation training equipment.

[Research on measuring the velocity and displacement of the coxa and knee based on video image processing].

Based on repeated experiments as well as continuous researching and improving, an efficient scheme to measure velocity and displacement of the coxa and knee movements based on video image processing technique is presented in this paper. The scheme performed precise and real-time quantitative measurements of 2D velocity or displacement of the coxa and knee using a video camera mounted on one side of the healing and training beds. The beds were based on simplified pinhole projection model. In addition, we used a special-designed auxiliary calibration target, composed by 24 circle points uniformly located on two concentric circles and two straight rods which can rotate freely along the concentric center within the vertical plane, to do the measurements. Experiments carried out in our laboratory showed that the proposed scheme could basically satisfy the requirements about precision and processing speed of such kind of system, and would be very suitable to be applied to smart evaluation/training and healing system for muscles/balance function disability as an advanced and intuitional helping method.

[Research on video measuring method of knee joint angle based on cross ratio invariability].

With an un-calibrated camera a new method is proposed in this paper to measure dynamically the bending angle of knee-joint based on cross ratio invariability. Firstly, by video image processing technique, we detected 25 circular objectives distributed in the aided measurement tool and determined their geometric centers in the video frame respectively. Then we further computed the extending direction of thigh and shank by detecting position of two rectangular targets tied on them. Finally, using of the principle of cross ratio invariability in Projection Geometry, we could realize real-time dynamic measurement of the bending angle of knee-joint based on the method. Experiments have proved that the measurement precision of the introduced approach could satisfy basic requirements of clinical applications.

[Design and realization of training methods based on sit-to-stand balance ability training apparatus].

In this research, a new set of training methods was created and put into practice to train the body's sit-to-stand balancing ability, and controlling ability of body's gravity centre of patients with cerebrovascular diseases. It contains a series of motion trainings, including sitting position training, standing position training, sit-to-stand training and game training, etc. There is also a series of trainings of feedback included in this set of methods, such as internal feedback, external feedback, bandwidth feedback, conclusive feedback, visual feedback, acoustical feedback and so on. The trainings resulted in better controlling ability of body's centre of gravity in the sit-to-stand process of patients after a period of training. It indicated that these targeted-designed trainings, especially the feedback trainings, could effectively help the under-trained patients to have a better knowledge of their current situation, and in turn to have a better knowledge of which aspects they should take more training to achieve a better therapeutic effect.

Design and evaluation of a multimodal balance training system.

OBJECTIVE: Current balance training systems are designed exclusively for one particular type of training and assessment. Additionally, they comprise monotonous training programs. Therefore, patients in different stages of rehabilitation must use different balance training models from different manufacturers, resulting in high treatment cost. Furthermore, large spaces are required to accommodate the balance training machines, and doctors and physiotherapists have to learn to operate multiple machines. We aimed to design a multimodal balance training and assessment system that can accommodate the assessment and training of static, dynamic, reactive and proactive balance to satisfy individual needs. METHODS: The difficulty associated with combining static, dynamic, reactive and proactive balance training in a single system was to use radial and circumferential driving mechanisms together with a clutch mechanism, whereby circumferential and radial drivers were installed in the base of the system to drive a compound foot plate system with interchangeable springs, in order to adjust stiffness using the clutch. Based on the kinematic equation, the influence of system parameters on the change of the body's center of gravity were evaluated. The parameters included the radial offset of the driving mechanism (r), circumferential angle of rotation (θ), height of the base of the balance training system (h), horizontal distance between the body's standing center of gravity and the center of the foot plate (R), thickness of the padding mat (ΔH) and inclination angle (α). RESULTS: The difficulties associated with combining static, dynamic, reactive and proactive balance training models in a single system were solved using radial and circumferential driving mechanisms together with a clutch mechanism. The foot plate can swing back and forth within ±20° around the X-axis, swing left and right within ±20° around the Y-axis, swing diagonally within ±20°, swing 360° around the Z-axis, and adjust the height along the Z-axis. Furthermore, the inclination angle α, circumferential angle of rotation θ, and speed (dα/dt and dθ/dt) of the system can be controlled in real time. CONCLUSION: The developed balance training system is suitable for patients in different stages of rehabilitation. By providing multiple functionalities, this system can ensure high use rates, reduce costs and save space.

Rhizosphere soil microorganism populations and community structures of different watermelon cultivars with differing resistance to Fusarium oxysporum f. sp. niveum.

Fusarium wilt is an increasingly serious disease of watermelon that reduces crop productivity. Changes in microorganism populations and bacterial and fungal community structures in rhizosphere soil of watermelon cultivars resistant or susceptible to Fusarium oxysporum f. sp. niveum were investigated using a plate culture method and PCR-DGGE analysis. Plate culture showed that populations of culturable bacteria and actinomycetes were more abundant in the rhizosphere of the resistant watermelon cultivar than the susceptible cultivar, but the fungi population had the opposite pattern. Populations of Penicillium , Fusarium , and Aspergillus were significantly lower in the resistant cultivar than the susceptible cultivar at the fruiting and uprooting stages (p < 0.05). Pattern matching analysis generated the dendrogram of the DGGE results indicating the relatedness of the different resistant watermelon cultivars and their corresponding rhizosphere microbial communities. Further sequencing analysis of specific bands from DGGE profiles indicated that different groups of bacteria and fungi occurred in the rhizosphere of different watermelon cultivars. Our results demonstrated that plant genotype had a significant impact on soil microbial community structure, and the differences in the rhizosphere microbial community may contribute to the differences in resistance to F. oxysporum f. sp. niveum.