This article describes a 3D extension of Bresenham's algorithm and its implementation in the linear trajectory interpolation of CNC paths. The resulting algorithm has been successfully applied to a CNC milling machine that uses stepper motors as actuators, resulting in minimal contour errors for a given step motor resolution. A numerical control system that uses the algorithm implementation has been built as part of a wider effort which is to test the feasibility of building or retrofitting machine tools with CNC capabilities at an affordable price tag for a developing country. >

3-D CNC trajectory interpolation using Bresenham's algorithm

Tujuan dari penelitian ini adalah membuat CNC yang memiliki dua fungsi dalam satu sistem serta dioperasikan dalam satu interface. Dengan memanfaatkan USB serial untuk komunikasi antara komputer dan mikrokontroler. Program untuk mengoperasikan CNC dirancang dengan menggunakan perangkat lunak LabVIEW, program akan mengkonversi gambar menjadi G-Code dan mengirim G-Code ke dalam sistem CNC untuk melakukan proses plotter atau laser engraving. CNC Plotter dapat membuat sebuah pola gambar pada kertas dengan bolpoin secara otomatis. Sementara itu, CNC Laser Engraving dapat membuat sebuah gravir pada kayu dengan memanfaatkan panas laser berdaya 500 mw, panas laser akan mengikis permukaan kayu secara otomatis. Dalam merancang multi CNC dua buah motor stepper digunakan sebagai akuator penggerak sumbu, dan motor servo sebagai penggerak bolpoin. Berdasarkan hasil pengujian, program pada LabVIEW dapat mengoperasikan sistem multi CNC dalam satu interface. CNC laser engraving dapat melakukan proses grafir pada kayu, serta dapat mengatur ketebalan grafir sesuai dengan kebutuhan. Selain itu, CNC Plotter dapat mencetak sebuah gambar bidang berbentuk kotak dengan ukuran terkecil 2 mm x 2 mm, dan lingkaran dengan diameter terkecil 2 mm dengan tingkat keberhasilan 100%. Maksimal dimensi gambar yang dapat dikerjakan Multi CNC ini 300 mm x 300 mm.

Perancangan Sistem Multi Computer Numerical Control (CNC) untuk Plotter dan Laser Engraving

This study presents the development of a LASER power controller using pulse-width modulation (PWM) technique for the 3-axis computer numerically-controlled (CNC) LASER Machine. This includes the use of a graphical-user interface (GUI) and a GizDuino board to produce PWM outputs. The GUI was developed in Microsoft Visual Studio. The PWM code was programmed in the Arduino development environment. In this study, PWM is effective in controlling the LASER power of the Synrad firestar f201. Actual tests were conducted to verify its performance in an acrylic plastic material. PWM is also proven to be cost-efficient since it does not require additional modules for analog converters and signal conditioning process. Other features, like motor errors, LASER and chiller temperature, were also incorporated and created in the controls for the safety of the user and the machine hardware.

A pulse-width modulation (PWM) LASER power controller for the 3-axis computer numerically-controlled (CNC) LASER machine: Support program for the productivity and competitiveness of the metals and engineering industries

The objective of this thesis is to automate the manual 2D-patterned cutting of lace
with high a accuracy and quality of the cutting edges. Four main problems for
automating the cutting method were addressed; feature recognition technique for
cutting path extraction, material handling system, laser beam manipulation and
trajectory planning generation. An integrated mechatronic approach for designing the
automated laser cutting system was outlined.
The features of the 2D-patterned lace fabrics are not exactly identical and easily
distorted nonlinearly due to handling operations. An active template matching
technique was developed and implemented to recognise the distorted features of the
2D-patterned shape cuttings. To accommodate the geometrical pattern variations,
the cutting paths of the 2D-patterned shapes were extracted using either the chain-coding
technique or the binary morphological techniques. [Continues.]

Automated two-dimensional patterned shape cutting of elastic web materials

Precise and fast position measurement has been a challenging problem in computerized
numerical controller (CNC) machines where parts need to be processed at a high speed.
This paper inspects data acquisition and processing on a high-speed tube cutting Siemens
840D CNC machine with Windows NT.40 operating system and analyzes the constraints
of the old procedure on the production speed. The more efficient technical tactics are
proposed and implemented. The laser is added to the system to perform the same data
acquisition while the function of the capacitive sensor is kept. A dual data acquisition
system is thus created and the old one functions as a backup. In the retrofit, the affordable
and practical data communication method is used, the sensor physical movement is
avoided, the algorithm is optimized with requirement of less data, and computation of the
algorithm is moved from numerical controller unit (NCU) to personal computer unit
(PCU). For every tube part, the laser approach reduces the data acquisition and
processing time to 4 seconds, compared to 12 seconds with a capacitive sensor.

/pdf/conception-and-implementation-of-a-dual-data-acquisition-2oyj2jfww7.pdf

Conception and Implementation of a Dual Data Acquisition System on an Eight-Axis High-Speed Tube Cutting CNC Machine

This article describes the design and construction of a low power laser cutting machine with three degrees of freedom for applications such as wood, textile fabrics and the like. An available 10 Watt laser gun is used to provide the cutting mechanism. The results show that such a machine is feasible at a reasonable cost for applications where speed and repeatability are more important than high precision and power. >

L.E. Chiang

Papers

CNC control of a laser cutting machine