The machining of large workpieces (larger than 1 m3 in volume) and with high added value, require long prior set-up processes in the machine, sometimes longer than the machining time itself.
These workpiece set-up processes in the machine can be structured in two important phases:
First of all the measurement and best fit calculations that are usually carried out outside the machine.
The goal of this phase is to guarantee that the raw workpiece, coming from smelting, forging or mechanical welding processes, contains in all its volume the finished product to be achieved; that is, to guarantee that there is sufficient surplus in the raw material. Therefore, it is necessary to measure the raw workpiece and to compare this volume with the theoretical measurements of the finished product.
These comparisons must be used to calculate the correct best fit of the workpiece in the machine in order to guarantee said surplus material in each and every one of the surfaces to be machined; where the result is the definition of positions of certain key references of the raw workpiece in the machine´s coordinates system.
Secondly, and once the workpiece is positioned in the machine, the part alignment operations according to the prior calculations.
A consequence of these operations is a further increase in the duration of the entire process, of even greater importance as these unproductive times occupy machine capacity. In this phase it is necessary to position the workpiece according to the prior references and to correct its position by measuring these references, until the final alignment is guaranteed according to the previously established calculations.
The problem of duration is mainly due to the slow and tedious processes used for these necessary operations aimed at guaranteeing the quality of the subsequent machining. As for the technologies available, these include either traditional measurement and calculation processes or the use of expensive, complex and over dimensioned technologies for this specific purpose, such as laser trackers or scanners.
Aware of this issue which concerns machining workshops, foundries and the metal fabrication of voluminous workpieces, SORALUCE has developed with its technology centre an innovative technology which will enable the execution of these processes in a much faster and safer manner. A technology that is already patented and called VSET, which will set new quality standards in the set-up phases.
VSET is a platform based on 3D photogrammetric vision which consists of various hardware and software systems which we have developed ourselves. The photogrammetric vision system makes it possible to achieve an alignment precision of up to 0.1 mm/m in a fast, reliable and simple manner. In short, tolerances that are more than sufficient for these processes.
The modular configuration of the product corresponds respectively with the previously described phases of the raw part measurement and best fitting.
The measurement module mainly consists of set of optical markers and calibrated bars, a self-calibrating digital photogrammetry camera and a laptop, all presented in trolleys and safety cases that are easily used in these industrial environments. The laptop contains measurement software that is capable of configuring the scatter plot of the part´s geometry based on the photos that are obtained of the workpiece.
On the other hand, the best fit module is a software development related to the measurement module, which based on optimisation algorithms almost immediately carries out the 3D best fit calculations of the finished workpiece, comparing it with the scatter plot that defines the raw workpiece.
The result of this measurement and best fit is a references report that will make it possible to carry out the alignment in the machine in a simple manner by means of set-up procedures that are usually already integrated in the machine.
VSET is a system is an accessory external to the machine by SORALUCE. SORALUCE is developing and will soon launch an upcoming development intended for its specific machines. This new software module will enable the automatic integration of best fit results in the machine’s control, and by means of calculation algorithms will make it possible to carry out an automated and guided alignment process, facilitating and further reducing the times for this task.
The VSET system is already a system that has been previously tested with great success in industrial environments where truly spectacular quantitative and qualitative results have been obtained in the following critical factors summarised below:
- Reductions in measurement, best fit and alignment processing times of up to 70%.
- Increases in machine availability and productivity thanks to transferring set-up times in measurements, adjustments and corrections to an environment outside the machine.
- Given its ease-of-use, it offers access to these processes to professional profiles that are not specialised in measurements.
- Standardisation of alignment procedures in the machine.
- Guaranteed quality based on the digital record of the entire process and potential traceability.
In short, VSET is another solution by SORALUCE that truly adapts to the problem of fine tuning workpieces with high added value and volume, placing this great company at the summit of industrial innovation.