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In high voltage substations, motors and sensors of a manipulator are susceptible to strong electromagnetic interference (EMI) and cannot work normally. The pneumatic motor can be a good method to overcome this problem. We present a novel five degree-of-freedom (DOF) manipulator design which is driven by pneumatic motors with no angle sensors. This design is simple but effective, and it can make the manipulator possess the potential to withstand the ultra-high voltage. It is also insensitive to EMI in high voltage substation due to its sensorless structure. The dynamic model of the wrist joint is established, and the state space equation, in which the pressure loss is contained, is proposed. The experiments are performed under different air pressures to validate the accuracy of the angle prediction model. A closed-loop control method, in which the angle prediction model is used as a feedback signal, is developed for this sensorless wrist joint. Finally, the rotation experiments were applied to test the validity of this control method, and the results showed that this method can improve the controllability of this type of wrist joint.INDEX TERMS Manipulators, pneumatic actuators, fluid dynamics, prediction methods.

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Microfluidic spun gelation mechacrylate (GelMA) microfiber has been widely utilized as a promising bioink for 3D bioprinting. However, its weak and easily tuned mechanical properties are still difficult to precisely evaluate, due to the lack of an effective stretching method. In this paper, we propose a force-control-based cyclic loading method for rapidly evaluating the elastic modulus: the E of the microfibers with different GelMA concentrations. A two-tube manipulation system is used to stretch microfiber with a non-destructive process. Based on the model reference adaptive control strategy, the stress response can be fitted into a sinusoidal wave when a small sinusoidal strain is automatically applied onto the microfiber. Afterwards, the maximum tensile stress and tensile stain is obtained to determine the E. Moreover, different stress amplitudes and frequencies are applied to form different stress-strain loops with almost same E. Compared with a frequently-used constant force loading method, the proposed method shows an obvious advantage in measurement accuracy, especially for low-concentration GelMA microfiber. Furthermore, the reasonableness of the measured E for different GelMA concentrations is confirmed by 3D cell culture experiments, and the results show the proposed method has great application potential to investigate the interaction between cell and fibrous bioink substrate.

According to actual control requirements, broadcast transmitter control system is designed with PLC as the core controller. The system hardware design is described and the software design is introduced in detail based on integrated development environment. Transmitter control system functions are realized. And the system can not only meet all the control requirements, but also has a powerful remote control ability and human-computer interaction with good reliability and real-time after the laboratory test and field test.

There are many river networks in Southeast plain cities of China, such as dense river network, many water projects, poor connectivity, strong pollution load into the river, and difficulty in regulation and control. The water environment problem of river network has become the bottleneck restricting the sustainable economic and social development of plain river network area. In order to improve the river water environment, it is very important to carry out reasonable intelligent regulation of regional river system. In view of the current situation that the water environment regulation is mainly based on manual operation and has not formed intelligent dispatching decision-making, this paper integrates the technology of water power and water quality joint control of urban river network, researches and develops the joint control and joint dispatching system of water environment improvement in plain river network area, and establishes a full coverage, full element three-dimensional monitoring and warning, dispatching and intelligent decision-making system, driven by monitoring data, with model as the core and remote control as the core with the goal of hydrodynamic, water level and water quality as the target, relying on the model cloud, the intelligent one click precise scheduling is realized.