in this paper we present a new method for tool-path generation and adaptive interpolation for a three-axis cnc milling machine. this method satisfied the force and / or the error conditions by using a variable-direction variable-feedrate strategy based on maximum feedrate map. the proposed adaptive interpolator modifies the cutting path and the moving direction according to the actual instantan...

The goal of this research is to improve the productivity of Numerically Controlled (NC) machine tools by optimization of feedrate settings. In this paper we compare the maximum cutting forces and cutting times using traditional methods with those achieved using the optimization methods developed in our research. Results indicate that significant productivity gains can be realized using the feed...

Interpolation techniques for CNC manufacturing systems are either of the ReferencePulse or ReferenceWord type. Reference-Pulse interpolations emit a sequence of pulses as reference signals to the control loops, whereas ReferenceWord interpolators provide binary words as references to Sampled-Data control/oops. In the present paper, a number of Reference-Pulse interpolation methods are described...

To achieve a desired fixed or variable speed (feedrate) along a given curved path, CNC machines employ independent motors to drive each of their axes in a time-coordinated manner. There are physical limits to the torque and power that the motors can supply, and the machine performance is compromised if the demands of overcoming machine inertia, cutting forces, and friction exceed these limits. ...

A dynamic cutting force and vibration model of the microendmilling process that accounts for the dynamics of the microendmill, influences of the stable built-up-edge, and the effects of minimum chip thickness, elastic recovery, and the elastic-plastic nature in ploughing/rubbing has been developed. Experimental validation has been performed, and the model is shown to predict the cutting force a...

This paper proposes an off-line feedrate scheduling method of CNC machines constrained by chord tolerance, acceleration and jerk limitations. The off-line process for curve scanning and feedrate scheduling is realized as a pre-processor, which releases the computational burden in real-time task. The proposed method first scans a non-uniform rational B-spline (NURBS) curve and finds out the cruc...

This paper presents a method for optimizing the machining parameters in rough turning processes to control the vibrations and deformations and minimize the production time per component under practical constraints. The optimization model is formulated, in which piecewise constraints are introduced based on the varying length-to-diameter (L/D ) ratio of the workpiece. The optimization problem is...

There are currently no analytical methods available which determine the exact arc length for NURBS curves and for this reason, a smooth feedrate profilewith desired trajectory cannot be achieved. Numerical methods used to calculate the arc length are time-consuming processeswhichmake generating a feedrate profile with desired accelerations difficult in real-time. This paper introduces a look-ah...

In this paper, the problem of time optimal feedrate generation under confined feedrate, axis accelerations, and axis tracking errors is considered. The main contribution is to reduce the tracking error constraint to constraints about the axis velocities and accelerations, when the tracking error satisfies a second order linear ordinary differential equation. Based on this simplification on the ...

Feedrate interpolation, which consists in generating the set points sent to the axis controllers from the initial path, constitutes a major line of the trajectory planning process. In multi-axis high speed machining the feedrate is usually evaluated by a kinematic method as the maximum feedrate respecting the joint velocity, acceleration an jerk limits. However this approach requires a difficul...