Parts with varied curvature features play increasingly critical roles in engineering, and are often machined under high-speed continuous-path running mode to ensure the machining efficiency. However, the continuous-pa...Parts with varied curvature features play increasingly critical roles in engineering, and are often machined under high-speed continuous-path running mode to ensure the machining efficiency. However, the continuous-path running trajectory error is significant during high-feed-speed machining, which seriously restricts the machining precision for such parts with varied curvature features. In order to reduce the continuous-path running trajectory error without sacrificing the machining efficiency, a pre-compensation method for the trajectory error is proposed. Based on the formation mechanism of the continuous-path running trajectory error analyzed, this error is estimated in advance by approximating the desired toolpath with spline curves. Then, an iterative error pre-compensation method is presented. By machining with the regenerated toolpath after pre-compensation instead of the uncompensated toolpath, the continuous-path running trajectory error can be effectively decreased without the reduction of the feed speed. To demonstrate the feasibility of the proposed pre-compensation method, a heart curve toolpath that possesses varied curvature features is employed. Experimental results indicate that compared with the uncompensated processing trajectory, the maximum and average machining errors for the pre-compensated processing trajectory are reduced by 67.19% and 82.30%, respectively. An easy to implement solution for high efficiency and high precision machining of the parts with varied curvature features is provided.展开更多
The supreme obstacle for sustainable development of natural resources is the scarcity bottleneck. So how to promote the sustainable utilizing and increase the using efficiency of natural resources is worth studying. T...The supreme obstacle for sustainable development of natural resources is the scarcity bottleneck. So how to promote the sustainable utilizing and increase the using efficiency of natural resources is worth studying. This pa-per suggests that we should improve the model and means of evaluating method and value management based on the theory of natural resource compensation. This paper discusses the User Cost Method based on the microeconomic aspect which can change the evaluating method for natural resources. From the perspective of value management model, we should use the User Cost Method to realize the linkage and integration of micro and macro compensation for natural resources. Based on the evaluating and accounting idea of User Cost Method, this paper presents a theo-retical framework to harmonize and link micro and macro compensation for natural resources. At present, we should seek the new approach and method to manage natural resources, so can we realize the capitalization management focusing on the value management for natural resources.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.51575087,51205041)Science Fund for Creative Research Groups(Grant No.51321004)+1 种基金Basic Research Foundation of Key Laboratory of Liaoning Educational Committee,China(Grant No.LZ2014003)Research Project of Ministry of Education of China(Grant No.113018A)
文摘Parts with varied curvature features play increasingly critical roles in engineering, and are often machined under high-speed continuous-path running mode to ensure the machining efficiency. However, the continuous-path running trajectory error is significant during high-feed-speed machining, which seriously restricts the machining precision for such parts with varied curvature features. In order to reduce the continuous-path running trajectory error without sacrificing the machining efficiency, a pre-compensation method for the trajectory error is proposed. Based on the formation mechanism of the continuous-path running trajectory error analyzed, this error is estimated in advance by approximating the desired toolpath with spline curves. Then, an iterative error pre-compensation method is presented. By machining with the regenerated toolpath after pre-compensation instead of the uncompensated toolpath, the continuous-path running trajectory error can be effectively decreased without the reduction of the feed speed. To demonstrate the feasibility of the proposed pre-compensation method, a heart curve toolpath that possesses varied curvature features is employed. Experimental results indicate that compared with the uncompensated processing trajectory, the maximum and average machining errors for the pre-compensated processing trajectory are reduced by 67.19% and 82.30%, respectively. An easy to implement solution for high efficiency and high precision machining of the parts with varied curvature features is provided.
文摘The supreme obstacle for sustainable development of natural resources is the scarcity bottleneck. So how to promote the sustainable utilizing and increase the using efficiency of natural resources is worth studying. This pa-per suggests that we should improve the model and means of evaluating method and value management based on the theory of natural resource compensation. This paper discusses the User Cost Method based on the microeconomic aspect which can change the evaluating method for natural resources. From the perspective of value management model, we should use the User Cost Method to realize the linkage and integration of micro and macro compensation for natural resources. Based on the evaluating and accounting idea of User Cost Method, this paper presents a theo-retical framework to harmonize and link micro and macro compensation for natural resources. At present, we should seek the new approach and method to manage natural resources, so can we realize the capitalization management focusing on the value management for natural resources.
