Interactive fixture and tool space design considering tool movement, machine, and inspection for five-axis grinding

2009 ◽  
Vol 224 (4) ◽  
pp. 543-552
Author(s):  
Y Wang ◽  
Z-J Wang ◽  
O Yilmaz ◽  
N Gindy
Keyword(s):  
Degrees Of Freedom ◽  
Simulation Software ◽  
Grinding Wheel ◽  
Space Design ◽  
Physical Experiments ◽  
Cutting Out ◽  
Machine Centre ◽  
Grinding Machine ◽  
Grinding Operations ◽  
Five Axis

This paper proposes a novel method of collision-free fixture and tool space design for five-axis grinding, considering tool movement, machine degrees of freedom, the machine envelope, inspection, and related features. The fixture space is designed in three steps. First, the fixture space is generated as the remaining space after cutting out the tooling space (i.e. the sweeping space of the grinding wheel along the profile of the machined features). In this way, the fixture space is naturally collision-free with respect to tool movement. Second, the fixture space is further modified based on the constraints imposed by the grinding machine centre, which include over-travel distance, the positions of coolant nozzle and wheel dresser, and so on. Third, the fixture space is modified again according to measurements conducted by coordinate measuring machines and in-cycle machine probes. Interactions of fixture space with tool space, machine, and inspection are considered. The fixture space design for holding aerofoil blades on a five-axis machining centre Makino A55 for grinding operations is used as a case study, and the results of this study have been verified by computer-aided manufacture (CAM) simulation software Vericut and physical experiments using dummy wheels.

Tool Path Planning and NC Generation of Tilted Plane Machining Features for Five-Axis Machining

2011 ◽  
Vol 697-698 ◽  
pp. 309-313 ◽  
Author(s):  
Chen Hua She ◽  
Yueh Hsun Tsai
Keyword(s):  
Machine Tool ◽  
Degrees Of Freedom ◽  
Tool Path ◽  
Simulation Software ◽  
Free Form ◽  
Parent Child Relationship ◽  
Machining Feature ◽  
Machining Errors ◽  
Tilted Plane ◽  
Five Axis

Designs of free-form surface products are becoming increasingly complex. In traditional three-axis machine tool machining, errors that are caused by repetitive positioning and the costs of fixture jig design and manufacturing are critical. Since multi-axis machining provides two more rotational degrees of freedom than a three-axis machine tool, the former can solve these problems, and has therefore become the trend of precision cutting. As multi-axis machined parts often have holes and grooves on the tilted plane, this work proposes a method for machining tilted working plane features and for NC generation on a five-axis machine. The developed module can provide common geometric features, allowing the user to alter the machining feature and sequence on the tilted plane quickly using the parent-child relationship in a tree diagram, and plan the tool path. The postprocessor module developed in this paper can transform the tool path into an NC program required for machining. Finally, solid cutting simulation software is utilized to confirm the feasibility and correctness of the tool path and NC data of the tilted plane machining feature.

Principal Curvatures and Cutter Location Calculation of Six-Axis CNC Abrasive Belt Grinding Machine

2010 ◽  
Vol 139-141 ◽  
pp. 1328-1332
Author(s):  
Guang Ling Wu ◽  
Qiu Ju Zhang
Keyword(s):  
Simulation Analysis ◽  
Grinding Wheel ◽  
Machining Accuracy ◽  
Automatic Programming ◽  
Principal Curvatures ◽  
Validity And Reliability ◽  
Belt Grinding ◽  
Modified Method ◽  
Grinding Machine ◽  
Five Axis

A six-axis CNC belt grinding machine automatic programming technology was studied in this paper, and which used D-H rule to solve out five-axis motion variables (the DOF of A, B, X, Y, Z), then discussed the problem of maximum contact degree between the grinding wheel and contact surface, and solved out the C-axis motion variable (the sixth DOF) by the direction of principal curvature in each cutter location point, after that gave a modified method of C-axis motion variable to smooth the machining. In order to ensure the machining accuracy while improving the machining efficiency, the paper summarized the self-adaptive spacing and step distance calculation method. The results which verified by a simulation analysis were validity and reliability, and provide a new thinking and beneficial reference for the research of other similar NC programming technology.

Evaluating the influence of grinding mode on part’s accuracy and grinding wheel’s wear in grinding profile for ball bearing's inner ring groove

2018 ◽  
Vol 56 (4) ◽  
pp. 531
Author(s):  
Nguyen Anh Tuan ◽  
Vu Toan Thang ◽  
Nguyen Viet Tiep
Keyword(s):  
Theoretical Analysis ◽  
Current Issue ◽  
Grinding Wheel ◽  
Machining Accuracy ◽  
Ring Groove ◽  
Production Practice ◽  
Wear Of Grinding Wheel ◽  
Output Factors ◽  
Grinding Operations ◽  
Technological Mode

Determining the influence of technological mode factors on machining accuracy is always an current issue in the production practice especially for grinding operations. This paper presents some research results to determine the effect of grinding parameters on grinding wheel’s wear and part’s accuracy in grinding profile for ball bearing's inner ring groove. From theoretical analysis and experimental results, the article assesses the influence of grinding mode factors on output factors. Based on that, the economic limitation wear of grinding wheel at three different grinding modes is determined.

scholarly journals Task space adaptation via the learning of gait controllers of magnetic soft millirobots

2021 ◽  
pp. 027836492110218
Author(s):  
Sinan O. Demir ◽  
Utku Culha ◽  
Alp C. Karacakol ◽  
Abdon Pena-Francesch ◽  
Sebastian Trimpe ◽  
...  
Keyword(s):  
Human Body ◽  
Degrees Of Freedom ◽  
Bayesian Optimization ◽  
Small Scale ◽  
Soft Robots ◽  
Modeling And Control ◽  
Walking Gait ◽  
Physical Experiments ◽  
Efficient Learning ◽  
Task Environments

Untethered small-scale soft robots have promising applications in minimally invasive surgery, targeted drug delivery, and bioengineering applications as they can directly and non-invasively access confined and hard-to-reach spaces in the human body. For such potential biomedical applications, the adaptivity of the robot control is essential to ensure the continuity of the operations, as task environment conditions show dynamic variations that can alter the robot’s motion and task performance. The applicability of the conventional modeling and control methods is further limited for soft robots at the small-scale owing to their kinematics with virtually infinite degrees of freedom, inherent stochastic variability during fabrication, and changing dynamics during real-world interactions. To address the controller adaptation challenge to dynamically changing task environments, we propose using a probabilistic learning approach for a millimeter-scale magnetic walking soft robot using Bayesian optimization (BO) and Gaussian processes (GPs). Our approach provides a data-efficient learning scheme by finding the gait controller parameters while optimizing the stride length of the walking soft millirobot using a small number of physical experiments. To demonstrate the controller adaptation, we test the walking gait of the robot in task environments with different surface adhesion and roughness, and medium viscosity, which aims to represent the possible conditions for future robotic tasks inside the human body. We further utilize the transfer of the learned GP parameters among different task spaces and robots and compare their efficacy on the improvement of data-efficient controller learning.

Calculation of Effective Ground Depth of Cut by Means of Grinding Process Model

2011 ◽  
Vol 496 ◽  
pp. 7-12 ◽  
Author(s):  
Takazo Yamada ◽  
Michael N. Morgan ◽  
Hwa Soo Lee ◽  
Kohichi Miura
Keyword(s):  
Process Model ◽  
Ground Surface ◽  
Depth Of Cut ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Wheel Wear ◽  
Elastic Deformations ◽  
Proposed Model ◽  
Effective Depth ◽  
Grinding Machine

In order to obtain the effective depth of cut on the ground surface, a new grinding process model taking into account thermal expansions of the grinding wheel and the workpiece, elastic deformations of the grinding machine, the grinding wheel and the workpiece and the wheel wear was proposed. Using proposed model, the effective depth of cut was calculated using measured results of the applied depth of cut and the normal grinding force.

Study on Grinding Technology of Electrical Discharge Grinding of Curve Edge Polycrystalline Diamond

2006 ◽  
Vol 304-305 ◽  
pp. 206-209 ◽  
Author(s):  
Gang Liu ◽  
Ming Chen ◽  
Z.G. Hu ◽  
X.F. Zhu ◽  
H. Xu ◽  
...  
Keyword(s):  
Surface Quality ◽  
Electrical Discharge ◽  
High Efficiency ◽  
Practical Significance ◽  
Cnc System ◽  
Milling Cutter ◽  
Curve Edge ◽  
Grinding Machine ◽  
Five Axis ◽  
Pcd Tools

PCD tools, especially curve edge PCD compound tools are used widely in machining nonferrous and non-metal materials with high efficiency and precision because of their excellent cutting properties. But high quality grinding of PCD tools is the uppermost obstacle in application because there are great difficulties to profile and sharpen edge in grinding, especially for milling cutter and drill with curve edge. This paper studied technology of wire EDG curve edge PCD compound tools by wire electrical discharge grinding machine with five-axis CNC system. The grinding quality was evaluated by scanning electron microscope (SEM) and roughometer. Three steps processing technique (roughing, finishing and fine finishing) and optimal process parameters of wire EDG PCD tools were recommended after considering synthetically the surface quality, precision and machining efficiency. The results met the requirement of high surface quality, precision and efficiency. This paper also applied successfully the optimal technology to grind a PCD milling cutter with outer and inner blade by electrical discharge grinding machine with five-axis CNC system. By the optimal parameters, the process yielded high precision of ±4.3µm and low roughness of 0.30µm. Experiment results have great practical significance to the high precise and efficient wire EDG of PCD tools.

Methodology for Evaluation of Treated Steels and Alloys in Abrasive Processing

2021 ◽  
Vol 410 ◽  
pp. 262-268
Author(s):  
Vyacheslav M. Shumyacher ◽  
Sergey A. Kryukov ◽  
Natal'ya V. Baidakova
Keyword(s):  
Physical And Mechanical Properties ◽  
Metals And Alloys ◽  
Grinding Wheel ◽  
Measuring Instruments ◽  
Abrasive Machining ◽  
Machining Performance ◽  
Abrasive Grains ◽  
Abrasive Tools ◽  
Composition Structure ◽  
Grinding Operations

One of the critical physical and mechanical properties of metals and alloys is the suitability for abrasive machining. Machining by abrasive tools is the final operation that sets the desired macro-geometry parameters of processed blanks and microgeometry parameters of processed surfaces such as roughness and length of a bearing surface. Abrasive machining determines the most important physical and mechanical parameters of a blank surface layer, i.e. stresses, phase composition, structure. Machinability by abrasive tools depends on the machining performance affected both by the blank material properties and various processing factors. In our previous studies, we proved that during abrasive machining the metal microvolume affected by abrasive grains accumulates energy. This energy is used for metal dispersion and is converted into heat. According to the theoretical studies described herein, one may note the absence of a reliable and scientifically valid method as well as measuring instruments to determine the machinability of metals and alloys by abrasive tools. For this reason, we suggested a method simulating the effect the multiple abrasive grains produce in a grinding wheel, and enabling us to identify machinability of metals and alloys, select the most efficient abrasive materials for machining of the same, and form the basis for development of effective grinding operations.

scholarly journals Grinding of AISI 4340 steel with interrupted cutting by aluminum oxide grinding wheel

2015 ◽  
Vol 68 (2) ◽  
pp. 229-238
Author(s):  
Hamilton Jose de Mello ◽  
Diego Rafael de Mello ◽  
Eduardo Carlos Bianchi ◽  
Paulo Roberto de Aguiar ◽  
Doriana M. D'Addona
Keyword(s):  
Aluminum Oxide ◽  
Rotation Speed ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Wheel Wear ◽  
Machined Surface ◽  
Aisi 4340 Steel ◽  
4340 Steel ◽  
Grinding Machine ◽  
Aisi 4340

AbstractThere has been a great advance in the grinding process by the development of dressing, lubri-refrigeration and other methods. Nevertheless, all of these advances were gained only for continuous cutting; in other words, the ground workpiece profile remains unchanged. Hence, it becomes necessary to study grinding process using intermittent cutting (grooved workpiece – discontinuous cutting), as little or no knowledge and studies have been developed for this purpose, since there is nothing found in formal literature, except for grooved grinding wheels. During the grinding process, heat generated in the cutting zone is extremely high. Therefore, plenty of cutting fluids are essential to cool not only the workpiece but also the grinding wheel, improving the grinding process. In this paper, grinding trials were performed using a conventional aluminum oxide grinding wheel, testing samples made of AISI 4340 steel quenched and tempered with 2, 6, and 12 grooves. The cylindrical plunge grinding was performed by rotating the workpiece on the grinding wheel. This plunge movement was made at three different speeds. From the obtained results, it can be observed that roughness tended to increase for testing sample with the same number of grooves, as rotation speed increased. Roundness error also tended to increase as the speed rotation process got higher for testing the sample with the same number of grooves. Grinding wheel wear enhanced as rotation speed and number of grooves increased. Power consumed by the grinding machine was inversely proportional to the number of grooves. Subsuperficial microhardness had no significant change. Micrographs reveal an optimal machining operation as there was no significant damage on the machined surface.

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