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In order to solve the problem of energy crisis and take the road of sustainable development, the development of renewable energy and recycling of low-grade waste heat have attracted more and more attention. As a new type of volumetric energy conversion device, scroll expander is wi dely used in Organic Rankine Cycle (ORC) waste heat recovery, because of its advantages such as small size and so on. Scroll profile is one of the main factors affecting scroll expander performance. Compared with the traditional constant section scroll profile with same suction volume, volume ratio and shell size, the new type of variable section scroll profile could reduce scroll tooth height, better mechanical properties and improve efficiency, therefore making it more suitable for working under complex operating conditions. In order to reduce the head invasion rate, airflow friction factor, the power loss at the air inlet, and improve the pneumatic power conversion efficiency, a new head correction method is proposed. Although R123, R134 and R245 are the most commonly used working medium in scroll fluid machinery, the selection of working medium in scroll expander is still a key problem. The overall performance of the scroll expander can be improved by designing different inlet shapes and positions or double-symmetrical exhaust ports. The radial leakage caused by axial clearance of scroll expander can be improved by developing new scroll profile to reduce the length of radial leakage line and optimizing the design of scroll top sealing mechanism. The tangential leakage caused by radial clearance can be improved by enhancing the manufacturing precision and installation accuracy of scroll plate and designing the radial variable mechanism. At present, fewer research has been carried out on the leakage of scroll expander. Therefore reducing the leakage loss to improve the performance of scroll expander is of great significance in the future research.

In order to replace the climbing work of the first climbers of the transmission tower without safety ropes, a transmission tower climbing robot is designed in this paper. First of all, this paper designs the structure of the robot by imitating the silkworm crawling on the branches through the principle of bionics. On this basis, through the inverse kinetics solution method, under the premise of planning the gait of the robot first, the dynamic simulation analysis of the robot is carried out according to the gait, so as to obtain the torque required for each joint motion. At the same time, according to the simulation results, the experimental test of the robot is carried out. Experiments have shown that the robot can climb to the top of a 50 m high transmission tower in 70 min with a load of 10 kg. The research results show that the transmission tower robot can replace the manual climbing operation of the transmission tower, and the mechanization and intelligence of the high-altitude operation of the transmission tower is highly feasible.

Service robot research has developed very rapidly in the recent few years, the restaurant service robot has been the most important part of the research. In this paper, a dining service robot working on the overhead monorail is designed to deliver food instead of waiters. The content of this dissertation involves the design and development of the control system of it, including hardware and software. It is composed of the main controller, DC motor driving module, RFID read-write positioning module, and signal gathering module. A control platform was developed to monitor the robot's running state and delivery status in real-time. And then, a two-layer fuzzy control algorithm was proposed to improve the motion control precision of the robot. The experimental results show that the dining service robot using this control system has the advantages of high positioning accuracy, fast response, and strong robustness.

With the development of society, the energy crisis has become increasingly prominent, which greatly affects the sustainable development of the economy of various countries. Industrial energy consumption accounts for more than 70% of China’s total energy consumption, of which more than 50% is converted to industrial waste heat, and recyclable waste heat resources account for about 60% of the total waste heat resources, while China’s current utilization rate of industrial waste heat only reaches about 30%. The development of renewable energy and recovery of low-grade waste heat in industry is the key to solve the problem. As a type of volumetric expander with full flow expansion, the screw expander is extensively applied in the industrial waste heat recovery and geothermal energy generation industry because of its effective utilization of low enthalpy energy. Improving the performance of the screw expander as the core, the paper concludes and summarizes the research status of the leakage, rotor geometry, sealing and lubrication, processing and manufacturing, which can affect the performance of the screw expander. In addition, it also introduces the application status and potential utilization of screw expander.

As an important part of a micro-compressed air energy storage system, the scroll expander directly affects the efficiency of the whole energy storage system. The effects of resistance on the efficiency of scroll expander caused by inlet structure and size are discussed with theory analysis and experimental methods in this paper. Micro-compressed air energy storage system has aroused widespread attention because of its pollution-free, high flexibility, in the community, remote areas power supply. Comprehensive experimental work with the selections of different size and structure of the air inlet of the scroll expander was performed with the cutting angle of air inlet chamber of the scroll expander. The results of the experiments are discussed on how exergy efficiency and inlet flow of the scroll expander were affected resulting from the cutting angles dissected. The results show that a maximum value exists for exergy efficiency of the scroll expander. Therefore, the exergy efficiency of the scroll expander can be effectively improved by enlarging the air inlet port dimension and modifying the size of air chamber.

With the increase of power generation from renewable energy sources and due to their intermittent nature, the power grid is facing the great challenge in maintaining the power network stability and reliability. To address the challenge, one of the options is to detach the power generation from consumption via energy storage. The intention of this paper is to give an overview of the current technology developments in compressed air energy storage (CAES) and the future direction of the technology development in this area. Compared with other energy storage technologies, CAES is proven to be a clean and sustainable type of energy storage with the unique features of high capacity and long-duration of the storage. Its scale and cost are similar to pumped hydroelectric storage (PHS), thus CAES has attracted much attention in recent years while further development for PHS is restricted by the availability of suitable geological locations. The paper presents the state-of-the-art of current CAES technology development, analyses the major technological barriers/weaknesses and proposes suggestions for future technology development. This paper should provide a useful reference for CAES technology research and development strategy.

Traditional inspection robot for high voltage transmission line robot is hard to cross the drainage line and other non straight line segment obstacle because of the small operation space. A new bionic structure of the inspection robot is proposed in this paper, which is combined the motion characteristics of primates with the modern design method and the principle of bionics. The mechanism model based on the three arms with symmetrical distributed and its crossing various obstacles on power line simulating to primates suspension pendulum movement are presented. The robot operation of crossing obstacle process is simulated and analyze with ADAMS software, thus the rationality and stability of the bionic mechanism are verified. Finally, the principle model and virtual prototype of robot are manufactured and testing on the practical power line.

In China, many traditional industrial processes need to be maintained and upgraded to incorporate new technology development. The paper reports our work in improvement of the traditional dyeing process using advanced network control technology. Based on a dyeing industry, we designed the network system of dyeing equipment using industrial Ethernet & Multi-bus technology. The system takes three-level structure: factory management level, workshop control level and field equipment level. Field equipments comprise some PLC and frequency conversion control systems; workshop level adopts two Siemens PLC to centrally control field equipments; HMI, monitoring room PC and remote office PC monitors and manages workshop control level. The network system has multi-stage monitoring, access control and remote alarm functions, realized management - control integration.

Based on the problem that the control system of rotary screen printing machine can not on-line inspect and real-timely adjust off pattern in the process of printing, an automatic inspecting registration system is designed by images of pattern position marks on both sides of fabric in wax dying. The images of pattern position marks before printing are captured by a CCD image sensor, and the real distance about the current pattern and the error between the measured value and the standard value are calculated, which are used to estimate the registration precision and produce the control pulse for regulating the rolling speed. After printing, the effect of dynamic adaptation is given by another CCD image sensor and according to the feedback the secondary adjustment is made. In this way, the closed-loop registration system for rotary screen printing machine is realized that will raise the quality and the productivity of printing.

The mechanical structure and control system for a new crawler type of robots is presented in this paper. The type of the robot is designed for power transmission line inspections. The new crawler type of the robot is composed of three arms and a balance mechanism, which are all joined together through a base. The distributed and hierarchical control strategy for this new robot is proposed in combination with a rule based expert system for optimal decision making. The proposed control strategy has been organized into three levels hierarchically. Compared with other robot structures, this new type of robot has a simpler structure. It has been proved that this type of new robot has higher efficiency in obstacle crossing through the simulation and experiments operating with the prototype of the model machine. Its intelligent control strategy has demonstrated its competitive advantages. The crawler type inspection robot is a attempt for developing a new robot structure to be used for high voltage power transmission line inspection.

The paper presents a thermodynamic model for a scroll compressor used for Compressed Air Energy Storage. The model includes energy conservation equation, instantaneous volume equation and gas leakage equation. The numerical simulation results are achieved by means of the 4th order Runge-Kutta method under Matlab and are compared with the experimental values. Different performance parameters of the scroll compressor including the delivery, pneumatic power and energy conversion efficiency are analyzed. The comparison between the simulation and the experiment indicates that all the parameters show the same changing trend with some deviation, which may be caused by some ignored factors in the thermodynamic model like the heat loss, the throttling loss and the mechanical friction loss. Finally the paper provides the suitable running conditions for the experimental prototype.

The noise attenuate of resistance muffler has been studied with the pressure signals of resource noise and the noise exhausted out of muffler with different diesel rotational velocity collected, and the acoustics performance of the double noise has been researched with the signal spectrum analysis. Corresponding conclusions have been obtained as following: the resource noise has similar spectrum performances under different discel rational speed; the amplitude of resource noise increases with the diesel rotation rising; the resistance muffler used on the excavator has good noise attenuate at different speed of diesel rotational velocity, and the insert loss increases with the diesel rotational velocity rising.

The paper mainly expatiates on control theories, parameters, and transfer functions for electronic expansion valve system. It realizes optimal fuzzy PD controller with more conspicuous effect, and can be put to use in flux process control with high precision. The paper, in the meantime, illustrates the hardware connection, control theory, driving flow chart of stepper motor, and flow chart of the optimal fuzzy control process.