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The system which could be described as "trinity, seven subsystems" has realized automatic remote control of the machine working process with orientation, localization and formalization. At local place, it realized automatic position and pose online detection, automatic orientation tunneling, automatic section cutting and forming and adaptive control of cutting arm swaying speed. It was the first time that realized absolute measuring of roadheader frame position and pose error under coal mine working condition in our country which could avoid error accumulation in relative measuring and guarantee the high precision of orientation tunneling. In underground remote, it realized remote monitoring, wireless remote control and video surveillance, thus realized remote control with multiple angles, visualization and one-button control under the condition of dustiness and vibration. At any network access point on ground using mining ring network, it realized real-time monitoring and displaying of roadheader running state parameters, and realized the functions of remote fault diagnosis and alarming. The whole system has been tested many times underground. The application results show that it is stable and reliable. With the development of automation, intellectualization, and informatization and other high technology, this system will be more and more suitable for fully mechanized excavation face.

Surface roughness is an important parameter to evaluate the quality of high-speed machining (HSM). This paper establishes a mechanical model based on the molecular-mechanical theory of friction to study factors that influence the surface roughness in HSM. The relationship between flow stress and the remnant height on the machined surface is obtained. The HSM process of AISI-1045 steel is simulated by using finite element method (FEM) based on DEFORM-2D and the flow stress is obtained. The surface roughness of workpiece machined by HSM is calculated based on the value of flow stress and the mechanical model. The result shows that the surface roughness of workpiece in HSM is acceptable, and the mechanical model supplies a method to study the surface roughness in HSM.

The gear honing process is a widely used process for gear finishing after heat-treated. The honing ring is profiled by diamond dressing gear, which have the profile of the workpiece to be machined and bonded a single layer of diamond particles. The paper has inroduced the traditional manufacturing methods of diamond dressing gears, positive electroplating and negative electroplating. Then put forward a new manufacturing method, Electroless nickel coating. Composition and condition of electroless composite plating solution, process steps are given. Several diamond dressing gears are made by this new method. Honing experiment testified that it is an applied method and has many advantages.

The gear honing process is a widely used process for gear finishing after heat-treated, and may be divided into the variants “internal-tooth honing” and “external-tooth honing”. External- tooth honing is seldom used in gear finishing due to lower overlapping ratio and relatively low precision. But its process cost is much lower than internal-tooth honing and gear grinding. The paper puts forward a new method to improve the precision of external-tooth honing, i.e. honing ring is profiled by diamond dressing gears, which have the profile of the workpiece to be machined. Meshing and Tooth contact analysis of honing ring profiling has been considered. Meshing equation of profiling process and equation of honing ring tooth flank after profiling are obtained. Experiment testified that it is an applied method and has many advantages.