Papers by Keyword: Five-Axis

Abstract: The precision of cutter grinding decides the level of cutting machining technology, and the precision of cutter is effectively improved through grinding by CNC technology. This paper first analyzed the key parameters of cutter grinding, and realized the functions of CNC five-axis grinding turning tool through design of the structure of CNC five-axis machine tool and building of the control system, to simplify the structure of machine tool, use open CNC control system, and reduce the cost of whole machine, convenient for promotion and use.

Abstract: Machining simulation is an important procedure to ensure machining safety and efficiency, especially for five-axis machining. The modelling for Fidia HS664RT five-axis machining center is firt established, and then the tool path for five-axis machining of centrifugal impeller is generated based on NX. The machining simulation is then implimented based on Vericut, and finally the actual machining is realized on Fidia HS664RT five-axis machining center. The machining results indicate the validity of the proposed machining simulation method.

Abstract: This paper presents process optimization for the five-axis milling based on the mechanics model explained in Part I. The process is optimized by varying the feed as the tool-workpiece engagements. The linear and angular feedrates are optimized by sequential quadratic programming. Sharp feedrate changes may result in undesired feed-marks on the finished surface. The adopted step is to update the the original CL file with optimized and filtered feedrate commands. The five-axis milling process is simulated in a virtual enviroment, and the resulting feedrate outputs are stored at each position along the tool path. The new feedrate profiles are shown to considerably reduce the machining time while avoiding process faults.

Abstract: In this article, a new method with Non-Uniform Rational B-Spline (NURBS) technology is presented and realized in a location and federate controlling system. In the method, the tool paths and the cutter locations (CL) were represented into NURBS curves based on the same knot vector. The above CL data was firstly calculated and then transformed to five motion commands of five axes of machine through the real-time post-procession algorithm. The acceleration/deceleration controlling method is also presented to avoid the impact of machine. The proposed 5-axis spline interpolation method is realized and the experimental result of machining shows that the method is valid.

Abstract: Five-axis CNC machine tools are constituted by three-axis machine tools and two rotational degrees of freedom. Using the two rotary axes, five-axis CNC machine tools can improve the accessibility and become an important means of machining complex surface parts. In order to get high tapered complicated curved surface parts, a dual turntable five-axis machine with A-C tables was introduced and the mathematical models of the CNC processing of the workpiece were established. Through machining experiment of the several major processed forms, it shows that the dual turntable five-axis machine system has high machining quality and could be used to machine the difficult-to-cut materials, spatial complicated curved surface parts and special requirements.

Abstract: Analysis impeller axis CNC machining process and processing content, applications Master CAM X6 software to generate a five-axis roughing trajectory of the impeller, the impeller expansion tank and wheels finishing trajectory, blade finishing trajectory. Vericut simulation software tool set, add the tool library, add rough, add impeller machining CNC program, set collision and interference color display, program optimization parameters, simulation of collision-free, without undercutting the five-axis impeller.

Abstract: The main purpose of this paper is to study the mechanisms of a new computer model of five-axis CNC machine tool developing process, including the kinematics of the spindle for both vertically and horizontally and its build process by simulation. According to the better process, let designer or user understands the characteristics of these particular machine tools. Through the computer simulation and graphic animation, users can observe the relationships of each movement on these new model multi-axis CNC machine tools. During the process of kinematics simulation, the forward and inverse kinematics are discussed and verified by simulation of software ADAMS. A control interface using Matlab is proposed to realize the motion commands and coordinate the kinematics. The simulated prototype demonstrates the feasibility in design through kinematics analysis of the new five axis CNC model in replace of conventional real prototype machine design.

Abstract: Five-axis flank milling is an important machining technique, especially in machining of complex parts. Tool posture vector can change easily using two axes of rotation to achieve optimum cutting conditions. However, the tool posture vector may change beyond the interpolation plane. This will result in overcut or undercut. In this paper, an adaptive interpolation algorithm of tool posture vector is proposed. In the proposed algorithm, the commanded feedrate for linear axis is kept constant for most time and adaptively adjusted to confine the chord error within a specified tolerance range during the interpolation process. The tool posture vector changes in the interpolation plane with a constant rotation degree. Simulation results from example are provided to verify the feasibility and advantages of the proposed scheme.

Abstract: Five-axis high speed machining can improve the efficiency and accuracy obviously, but the machining errors and tool interference are likely to happen due to the complexity of tool motion. So the collision detection and verification of tool path are very important and necessary before machining the part. Using a combination of process simulation and collision detection based on image analysis, a rapid detection approach is developed in this research. The geometric model provides the cut geometry for the collision detection and records a dynamic geometric information for in-process workpiece. For the precise collision detection, a strategy of image analysis method is developed in order to make the approach efficient and maintian a high detection precision. An example of five-axis machining propeller is studied to demonstrate the proposed approach.

Abstract: A vector calculation method is proposed to compute the tool envelope surface in five-axis machining. By introducing the typical five-axis machine tool motion, the velocity of cutter is obtained with rigid body motion theory. Based on envelope theory and some geometric characteristic of the cutter, the envelope condition is be simplified to find the grazing point with vector calculation method. The results can be applied to NC machining simulation, toolpath verification and optimization.