http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Mingyong Zhao (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Yong Zhang,Peiqing Ye,Hui Zhang,Mingyong Zhao 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.10
Linear toolpath, which is always in forms of a large amount G01 codes, is most popular in practical Computer Numerical Control (CNC) systems. The linear toolpath discontinuity will bring the unavoidable fluctuations on velocity and acceleration, leading to unsatisfied machining efficiency and quality. To improve the G01 machining, corners are normally smoothened by various smooth curves and in this paper, a novel two-step method including path-smoothing and feedrate scheduling is proposed. In path-smoothing, a B-spline curve is adopted to blend sharp corners locally and the smooth curvature along transition toolpath is obtained. With constrained chord error, the analytical curvature extreme is proved to occur at the B-spline midpoint and optimal curvature extreme is searched to enhance machining efficiency. In feedrate scheduling, based on the extreme points, a look-ahead methodology is utilized to determine the reachable feedrate at these critical points and a jerk-continuous scheduling scheme is developed afterwards. To verify the proposed method, tracking and machining experiments are conducted to demonstrate the efficiency, contour performance as well as machining quality compared to point-to-point and curvature-continuous methods.
-
Yong Zhang,Hui Zhang,Jiadong Shi,Jiali Jiang,Mingyong Zhao 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.1
Compared to conventional linear and circular segments, the parametric curve has advantages in approximating and machining, guaranteeing higher machining precision and better machining quality. Therefore, in Computer Numerical Control (CNC) systems, parametric toolpath has become more and more popular for its high-performance in practical machining and the performance of the parametric interpolator has become a standard to illustrate the advanced CNC systems. In this paper, adaptive-feedrate planning and the iterative interpolator have been developed to generate sampling points with respect to error and higher order kinematic constraints. Firstly, a jerk-limited feedrate profile and look-ahead algorithm are utilized to provide reachable feedrate at critical points. Afterwards, normal jerk (i.e. the jerk in a normal direction) are limited to improve machining precision and quality. In theory, it is proved that the normal jerk limitations have relationship with curvature derivative and a novel iterative interpolator is proposed to ensure the normal jerk limitation by considering the corresponding constraints at curvature derivative extreme points. Finally, simulation and experiments are conducted to demonstrate the efficiency and contour performance of the proposed method compared to conventional method and time-optimal method.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
