MTD-based Kinematics

Each machine tool can be described by its mathematical model, which is referred to as the Kinematic Model of the Machine. This model contains information used by the Autodesk Manufacturing Post Processor Utility to transform coordinates received from the CLDATA file (Model Coordinates) into coordinates of a machine tool (Machine Coordinates). This transformation is called the Inverse Kinematic Problem.

Solving this problem is one of the main tasks of the postprocessor and is more complex when handling multi-axis trajectories. To represent machine kinematics, Autodesk Manufacturing Post Processor Utility uses the Machine Tool Data Format, also called MTD-Format. Machine kinematics represented in this format are called MTD-Model. MTD-based machine kinematics representation is much more effective than the representation of kinematics by 3-axis, 4-axis and 5-axis classes, and also enables you to create programs for any configuration including 6-axis machines with 3 rotary axes.

The geometry of the machine can be defined either by a *.dmt triangle file defined in a CAD system or by parametric primitives (box and cone).

When creating your own MTD model, it is preferable to start from an existing MTD model and edit it.

Clicking Machine Tool tab > File panel > Import displays all the existing MTD files:

Warning: The sample MTD files supplied mathematically model the basic characteristics of a range of machine tools. Use them to understand how these machine tools move during the cutting of a part. These files do not accurately model the dimensions of the machine and exclude optional equipment that may be installed within the working volume. Consequently, collision checking with these files may fail to detect some collisions that can occur in practise. If you intend to rely on the collision checking functionality it is essential that you adjust the MTD file to match the exact dimensions and configuration of the machine you will be using.

For more information on how to improve collision checking, see Edit the .mtd file to improve collision checking.