Multirobot systems have shown great potential in dealing with complicated tasks that are impossible for a single robot to achieve. One essential problem encountered cooperatively working of the multirobot is unknown initial transformation relationships from hand eye, base base, and flange tool. In this article, multicoordinates calibration dual-robot system formulated matrix equation AXB = YCZ. A novel approach simultaneously solving unknowns YCZ proposed, which composed closed form method...

Industrial robots are characterized by good flexibility and a large working space, offer new approach for the machining of complex parts with small allowances (extra material allowed subsequent machining). Parts this type (such as aircraft skin parts, wind turbine blades, etc.) easily deformed due to their scale low stiffness. Therefore, these cannot be directly machined according designed model. A feasible method is plan robotic path using point clouds after clamping from onsite measurement...

In view of the problem that a lot heat is generated inside motorized spindle when it working, which causes thermal errors and affects processing quality, this paper optimizes Support Vector Regression through particle swarm algorithm to establish displacement model predict elongation change, To thermally compensate spindle. The sensors are arranged collect temperature rise data at different speeds according field distribution spindle's steady-state simulation analysis results. Taking as...

The high-speed motorized spindle is the core component of and high-precision machining, its compact structure leads to internal heat accumulation thermal deformation. Therefore, it great significance control temperature rise spindle. In order effectively spindle, a new spiral cooling system used analyze transfer mechanism coefficients are optimized based on gradient descent method combined with experimental data. coefficient taken as boundary condition finite element model, field prediction...

Focusing on the massive open online course (MOOC) platform, purpose of this study is to realize personalized adaptive learning according needs and abilities each learner. To end, author created a behaviour analysis model, designed MOOC platform based model. Through behaviours model digs deep into pattern behaviours, lays basis for intervention in process. The comparison ex-periments show that our prediction method more accurate than other predic-tion algorithms. This research sheds new light...

Aircraft skin parts are a typical kind of large size and thin wall which easily deformed in both clamping assembly. The edge needs to be machined before assembly control the clearances between adjacent skins after A frontier way is using robot system carry out large-range three-dimensional scanning, intelligentized calculation machining allowance automatic robotic milling. necessary premise for accurately calculating part. In this article, novel approach based on onsite measurement points...

Onsite surface inspection with a touch probe or laser scanner is promising technique for efficiently evaluating profile error. The existing work of 5-axis path generation bears serious drawback, however, as there drastic orientation change the axis. Such sudden may exceed stringent physical limit on speed and acceleration rotary motions machine tool. In this paper, we propose novel method onsite inspection. accessibility cones are defined used to generate alternative interference-free...

Abstract Cooling holes (number 100 ∼ 200, diameter 0.3 1.2 mm) are important heat dissipation structures of a turbine blade in aero-engine. Due to the small sizes and similar contours cooling holes, it is difficult extract match their features by traditional stereo reconstruction methods. This paper proposes novel hole inspection method for blades utilizing 3D technique vision, which combines vision principle with invariance cross-ratio. The feature points extracted matched calculating two...

Selecting the optimal machining parameters for impeller surface is a challenging task in automatic manufacturing industry, due to its free-form and deep-crooked flow channel. Existing experimental methods require lots of experiments off-line tests, which may lead high cost low efficiency. This paper proposes novel method optimization an based on on-machine measuring technique. The absolute average error standard deviation measured points are used define grey relational grade reconstructing...

The thermal error caused during the high-speed operation of a motorized spindle has significant impact on machine tool precision. In this paper, we firstly built, constructed an experimental platform for variable voltage preloaded spindle, used natural deceleration method to ascertain spindle's displacement and temperature information when bearing preload is 1400 N, 1450 1550 N 1700 combined with thermoelasticity theoretical analysis, affected by heat generation motor was separated, new...

Radial composite deviation is an important index to evaluate the precision of gear transmission, and its detection method also trend in industrial development. The ability predict radial while obtaining geometric gears a key challenge advancing intelligent online inspection within manufacturing workshops. This study presents virtual measurement for determining using point cloud data. involves optical three-dimensional scanner capture tooth surface data, profile deviation, applying reverse...

Abstract On-site inspection with a laser displacement sensor installed on the spindle of three-axis machine tool has found wide range applications in industrial processes. The calibration beam direction and integration on-site scanned points are crucial for measurement free-form surfaces. This paper presents method to calibrate unit vector integrate based standard ball. By scanning fixed ball, group nonlinear equations is constructed. solved by Levenberg–Marquardt algorithm get center...

This study proposes a quick and effective algorithm for screening severe N − 2 contingency, thus avoiding exhausting analysis of all conceivable contingencies. First, the index overload contribution rate (OCR) is developed on basis distribution factor, which discovered to be long‐tailed distributed by statistics. Then, fully exploiting feature, so‐called technique combination partitioned data sets (TCPDS) designed described. The core contingency apply TCPDS OCR. Moreover, an system...

Abstract Underground gas storage (UGS) is a method to ensure safe and stable supply of natural in China. The digital twin technologies, also known as Industry 4.0 play more important role intelligent development UGS. Based on the assisting production decision technology which contains data layer, model logic interaction constructed. layer covers from SCADA, equipment detection, GIS, etc. Using laser point cloud scanning, oblique photography, 3d design software, 3D achieves one-to-one...

Adaptively reconstruction of the skin surface covering skeletons aircrafts, ships, high-speed trains, buildings with steel frames, etc., based on on-site measured point clouds is an important issue in both industry and construction. However, skeleton has characteristics long narrow shape variable structure, resulting a sparse distribution cloud its different areas, which brings great challenges to surface. In this article, method for accurately reconstructing structures arbitrary distributed...

Finite Element Method (FEM) is pervasively used in most of 3D elastostatic numerical simulations, which Computer Aided Design (CAD) models need to be converted into mesh first and then enriched with semantic data (e.g. material parameters, boundary conditions). The interaction between CAD FEM stated above very intensive. Boundary (BEM) has been gradually instead recent years because its advantage meshing. BEM can reduce the dimensionality problem by one so that complexity generation...

If sampling frequency is not high enough, the efiect of adaptive memory polynomial predistortion linearizer very good for TWTA linearization. In order to keep valid, usually output power level must be reduced, which corresponds a reduced e-ciency TWTA. this paper, we present digital by combining LUT (Look-Up-Table) and memory-efiect compensation technique, may provide linear performance with less reduction relatively low frequency. The results simulations experiments show that linearity...