Methods and apparatus for shaping workpieces

Apparatus for shaping a workpiece, comprising:

• one or more databases configured to store:
• measurement data of a region of the workpiece to be shaped;
• data representing a required surface form of the said region of the workpiece surface;
• a processor means for:
• determining an amount and distribution of material to be removed, on the basis of the obtained measurement data and the data representing the required surface form;
• analysing the data representing the required surface form of the workpiece to determine form characteristics of the region to be shaped;
• determining a size and form of a shaping tool which can treat all parts of the region to be shaped on the basis of the determined form characteristics;
• and
• determining a tool path for moving the shaping tool over the region to be shaped in order to remove the material from the surface, wherein the tool path defines a tool offset at all points along the tool path, the tool offset being the amount of a deformation of the shaping tool against the workpiece surface, wherein the tool offset at all points along the tool path does not exceed a maximum tool offset and wherein the maximum tool offset is such that the shaping of the workpiece remains within a ductile regime at all points along the tool path;
• the apparatus further comprising:
• a means for providing a shaping tool having the determined size and form;
• a shaping machine including a fixture for mounting the shaping tool, the shaping machine further comprising a control means for controlling the fixture to move the shaping tool over the said region of the workpiece surface using the determined tool path in order to remove the material from the workpiece surface;
• wherein either:
• the shaping tool has an abrasive working surface or the apparatus is configured to provide, during shaping of the workpiece, an abrasive slurry between the shaping tool and the workpiece.

A system for shaping a workpiece, comprising:

• a plurality of shaping tools;
• a shaping machine for moving a shaping tool along a tool path over a workpiece;
• a measuring means to generate data representing an actual shape of the workpiece;
• one or more databases configured to store:
• data representing the actual shape of the workpiece;
• data representing a required shape of the workpiece;
• identity, form and wear data relating to each of the said plurality of shaping tools;
• a processor means for:
• determining a required form of a shaping tool on the basis of the data representing the required shape of the workpiece;
• selecting from said plurality of shaping tools a shaping tool which has the required form for shaping the workpiece;
• determining an amount and distribution of material to be removed from the workpiece on the basis of the data representing the actual shape and the data representing the required shape of the workpiece;
• determining a tool path for moving the selected shaping tool over the workpiece in a shaping operation to remove the said material from the workpiece;
• wherein the selected shaping tool and data representing the determined tool path are provided to the shaping machine;
• and
• the shaping machine is operable to shape the workpiece by moving the selected shaping tool over the workpiece surface along the determined tool path.