Simplifying Complex Motions

An all-in-one machine and motion controller is helping a machine builder set new levels of performance and economy in the stone cutting sector.

The new Quantum bridge saw from Farnese Australia provides X, Y and rotational motion for the fast and efficient shaping of stone kitchen and bathroom surfaces, and sets a new price/performance standard compared to existing machines in this market sector.

"The biggest challenge with application development was to simplify the operation of the machine," says Jason DeSouza, applications manager for Baldor Australia. "Farnese specified that the operator interface should not require any G-Code, or CAD/CAM software or special computer hardware."

Baldor controllers used in the application are programmed in a proprietary language called MINT that incorporates complex interpolated motion into a simple command set. This gives the programmer flexibility to generate motion profiles quickly and easily without the need for additional software.

"Machine cutting paths are based on a range of pre-defined geometric shapes and dimensional information entered by the user," says DeSouza. "These are used to calculate and pre-load motion commands which are executed in real time within the controller. Therefore, the machine does not experience any time delays associated with standard computer operating systems."

A unique user interface developed by Farnese makes selection of the right shape-cutting process very easy, avoiding much of the risk of operator error. A range of pre-programmed shape-cutting sequences are provided to cover common requirements, eliminating the need for skilled operator programming by the kitchen and bathroom surface suppliers that typically purchase these machines. The sequences include ready-to-use templates for the major sink manufacturers, for example. The interface also supports more complex applications, allowing programming using G-code as well as manual control.

The programming environment offers high-level keywords for the complex movements that Farnese requires, such as angular and circular cuts. Workbench also provides tools that allow Farnese to provide remote support for its machines, allowing diagnostics to be run and utilities for drive tuning.

Farnese Australia has been manufacturing stone-cutting and polishing machines for 10 years. With its latest product, the Quantum bridge saw, the company switched to an Ethernet-based NextMove e100 controller from Baldor. This provides all of the resources required for the real-time interpolated control of four servomotor axes, all of the I/O on the machine, plus an ActiveX interface to the unique Windows user interface that Farnese has developed over many years to simplify stonemasonry.

Quantum provides a large cutting area of 3.7 x 2m. Four servomotors control the motion of the rotary saw tool, which moves over the worktable on a gantry. Two synchronized axes drive the gantry along the worktable because of the weight and rigidity of the tool that is required for precision sawing over a large operating area. The other two axes provide transverse movement along the gantry, and rotational motion of the tool head. The latter axis eliminates the need to reposition the workpiece or tool for changes of cutting direction, and can make angular and circular cuts to radii as small as 10 mm. The four axes employ single-phase Baldor MicroFlex e100 drives driving BSM servomotors. These axes, plus all of the sensors and actuators required on the machine, are controlled by the motion and machine controller.

"The most significant technical aspect of the machine is the minimal hardware required," says DeSouza. "This is mainly attributed to the Ethernet Powerlink network used by the NextMove E100 controller and Microflex E100 servo drives."

The four servo axes on the machine are coordinated in real time through a single Ethernet cable. This reduces control wiring significantly while maintaining a very high level of performance and accuracy. Each servo drive is equipped with local digital I/O for end-of-travel and orient switches. This frees up the main controller to interface with general-purpose I/O required for the machine without hardware expansion modules.