Method of determining a local height of a build surface

Abstract

The invention relates to a fused filament fabrication device (1) comprising a print head (2) comprising a melt chamber (22) and a nozzle (4). The print head (2) is movably arranged relative to a build surface (10) in at least two perpendicular directions. A feeder (3) is arranged to feed filament material to the print head (2). A sensor is arranged to directly or indirectly measure a pressure in the melt chamber (22), the sensor producing pressure data. A flow sensor is arranged to measure a flow of filament into the print head (2) to obtain flow data. The device (1) also comprises a controller (7) arranged for a) controlling movement of the nozzle (4) over the build surface (10), b) controlling deposition of molten filament material on the build surface (10) during the movement of the nozzle (4), c) receiving the pressure data and the flow data, and d) determining a local height of the build surface (10) fora plurality of locations on the build surface (10), using the pressure data and the flow data.

Dependencies are inferred from the claim text.