The BTL format has become the standard exchange format in wood since its unification in 2006. It has been designed for the transmission of data from wood programs to production machines. In addition, it is used for data exchange between different program systems (CAD, optimization software, CAM systems).

In contrast to the “pure 3D format” exchange, the BTL contains a lot of additional information about the project, the individual components as well as the individual machining. The transfer of parent structures such as the use of the wall structure element or assembly is possible. Compared to CAD or BIM exchange formats, the BTL is very simple and contains exactly the information that is important for timber construction.

In order to facilitate the entry into the data exchange with the BTL and also to implement enhanced requirements for the future, the BTLx format has been developed.

The BTLx is based on the XML language. By using this schematic provided by design2machine, the development effort can be considerably reduced, in particular by using constraining control tools.

The system also uses the ability to check the syntax and structure of a BTLx file and the parameter value ranges. Thus, it can be automatically verified that a BTLx file meets the exact definition of the parameters.

Another advantage is the flexibility of XML, so that the evolution of the interface can be simplified.

Changes from the classic BTL format.

The BTLx format is an equivalence of the pure classical BTL format, so there are substantial similarities between the formats. However, concrete changes and improvements have been made.

• Components are now referenced using “GUID” and are therefore uniquely identifiable across project boundaries.
• The number of geometrically identical types of machining has been reduced and unified so that the implementation effort is reduced.
• The machining parameters have been given meaningful names.
• Problematic definitions related to certain parameter values have been corrected. Properties have been replaced by explicitly defined attributes.
• The machining mark has been simplified, the output text has been given to a separate machining.
• The definition of contour machining has been restructured and clarified.BTLx Innovations

In addition to the structural changes, some new features that are not listed in BTL have been developed for BTLx.

• In order to save and send files as compact as possible, a compressed version of the format with the file extension BTLz has been defined.
• Each BTLx file can contain a modification history. This can make it possible to understand when and from which programs the BTLx file was created or modified.
• The machining operations can be summarized in machining groups (e.g. in composite machining).
• In addition, external contours can now also be defined at the end of the bar to represent non-rectangular sections of components (e.g. round timber, I-beams, planks, …).

Prospects for BTLx

The format should be completed and expanded as before in a regular cycle. In addition to technical details and general improvements, more complex requirements (such as free-form surfaces or prefabricated geometries) will be implemented. The new BTLx format offers, through its flexible structure, optimal conditions for such future expansion.

Further information

For more information such as technical documentation, examples and the BTL viewer software visit : www.design2machine.com