MSc dissertation
proposal 2015/2016
Introduction:
Computer Numeric Control (CNC) machines can be
controlled directly [Yaman13]. However, the most common situation is that a host
computer produces motion commands for the machine, and the machine interprets
the motion commands by interpolating the given via points [Farouki14]. G-coding
(RS-274) is the oldest commanding language, and still the most commonly found
in CNC machines, but is in essence limited to the specification of lines and
arcs. More general curves, e.g. parametric curves as B-Splines
and NURBS, only recently started to be adopted in high-end CNC machines [Hu09].
There is however a large amount of work to be done to allow the technology to
be well integrated into most of the CNC machines.
Objectives:
The main objective of this work is the revision of
older interpolation methodologies, as the Digital Data Analyser (DDA), and the
proposal of novel interpolation methodologies which can be effective for
example NURBS. Interpolation can be designed to work both for single or
multiple axis CNC machines, in which case inverse kinematics needs to be
involved.
Detailed
description:
Interpolation is found in many domains of technology.
For example rendering in graphics cards has seen impressive results in the last
two decades. Interpolation research and development, within the printers and
CNC machining domains, evolve at a slower pace. In particular a number of
numerical interpolation modalities found in standard simulation tools, e.g. Matlab/Simulink, are yet to be thought for CNC. In this
work is proposed the study of Non-Uniform Ration B-Splines
(NURBS) in the vein of their rendering, i.e. their sampling (discretization) and interpolation.
The
work is therefore organized in the following main steps:
-
Do a historical research on DDA
-
Study and simulation of DDA
-
Study on parametric curves and inverse kinematics
-
Simulation of the rendering of NURBS
References:
[Yaman13] "Direct command generation for CNC
machinery based on data compression techniques", U. Yaman,
M. Dolen, Robotics and Computer-Integrated
Manufacturing 29 (2013) 344–356
[Hu09] "An Adaptive Real-time NURBS Interpolator
for CNC Machine Tools", H. Hu and X.T. Zhang,
2009 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, 2009
[Farouki14] "Inverse kinematics for optimal tool
orientation control in 5-axis CNC machining", Rida
T. Farouki, Chang Yong Han,ShiqiaoLi, Computer Aided Geometric Design 31 (2014)
13–26
Requirements
(grades, required courses, etc):
-
Expected
results:
At the end of the work, the students will have
enriched their experience in robot kinematics, control and interpolation.
Place
for conducting the work-proposal:
ISR / IST
More MSc
dissertation proposals on Computer and Robot Vision in:
http://omni.isr.ist.utl.pt/~jag