Abstract: A mechanical procedure is performed using a sequence of instructions generated from a relational data base. The data base includes at least one unit operation file containing data associated with the performance of a single unit operation, indications of prior operations that must be performed, and any support files that are required by each unit operation file. There is a generic instruction file containing a plurality of generic instructions. A sequence of unit operations to perform the mechanical procedure is first defined, using the information in the unit operation files. After this arranging of the unit operations, a series of task-specific instructions is generated for each of the unit operations by selecting and completing a series of generic instructions using information in each pertinent unit operation file.