Selecting a task in additive manufacturing

Apparatus comprising:

• a plurality of different types of components to perform different functions in an additive manufacturing process;
• and
• processing apparatus to:
• control the plurality of components to generate a three-dimensional object in a layer-by-layer manner by processing portions of successive layers of build material including forming a layer of powder and selectively solidifying the portions to cause the portions to coalesce, the portions of each layer of build material being processed within a predetermined layer processing time duration;
• and
• control the apparatus to perform at least one ancillary task in relation to at least one component of the plurality of components in accordance with a schedule, the ancillary task being performed within the predetermined layer processing time duration during the processing of a single layer or a plurality of layers.

A non-transitory machine readable storage medium containing instructions which, when executed by a processor, cause the processor to:

• control a plurality of different types of components that each performs a different processing function of an additive manufacturing apparatus to process portions of successive layers of build material including forming a layer of powder and selectively solidifying the portions to cause the portions to coalesce, the additive manufacturing apparatus for generating a three-dimensional object in a layer-by-layer process, wherein each layer of build material is processed within a predefined layer processing time duration;
• and
• control the apparatus to perform at least one maintenance operation in relation to at least one component of the plurality of components, in accordance with a maintenance operation plan;
• wherein the maintenance operation plan is such that the at least maintenance operation is completed within the predefined layer processing time duration for a single layer of build material or for multiple layers of build material.