With the increasing complexity of systems such as automobiles, trucks, airplanes, trains or power plants, access to maintenance procedures at the place of work is essential. Current maintenance procedures for these systems are costly and inefficient. Information can easily be out-of-date and not easily accessible at the place where it is needed. Maintenance manuals are often only available as hardcopy or on workstations far away from the airplane or automobile. In addition, the maintenance information is not tailored to the actual work order, requiring the mechanic to perform unnecessary steps before viewing the information that is actually needed to perform the repair.
Interactive Electronic Technical Manuals (IETMs) are key to more cost effective maintenance of complex systems. There are three related IETM challenges that need to be addressed:
1. Effective, distributed development and management of IETMs
2. Perform IETM inspections of systems by "annotating" the actual system with "stickies" that document any discrepancies discovered during the inspection.
3. Perform IETM maintenance where the procedures are read to the technician by a synthesized voice while the maintenance tasks are performed interactively
The following sections outline these challenges.
Currently, Original Equipment Manufacturers (OEMs) of subsystem components provide IETM documentation for their products to the system manufacturer for conversion, if needed, and inclusion into their system's overall IETM documents. An example is the documentation provided by an engine supplier to an aircraft manufacturer. This method of IETM development and management is usually very expensive because the OEM may use different or less effective authoring tools and processes and additional overhead costs of the system manufacture are typically added to those already charged by the OEM.
A new way is to distribute the IETM development and maintenance process across the OEMs, third party IETM authoring organizations, and system manufacturer, and transfer the IETM products directly to a central database (CDB) of the system's end user (e.g., the organization flying and maintaining the aircraft). After integration and quality control of the resulting IETM components by the engineering staff of the organization, the IETMs are then placed in an operational DB (ODB) for update of the IETMs in use by field technicians. The distributed development and management of IETMs involves these activities.
Conversion of paper-based maintenance information into IETMs by third party organizations and then transferred directly to the CDB
Authoring of IETMs by component manufacturers (OEMs) and then transferred directly to the CDB
Integration and quality control of the subsystem component IETMs at the CDB by the system user's engineering staff, and then transfer of the operational IETMs to an ODB
Update of field maintenance IETMs from the ODB
The goal of inspections is to find discrepancies between the specification and the actual status or behavior of a system. Example of discrepancies in an aircraft can be corrosion at the surface or low oil in the engine. Currently, inspections are performed using an IETM check list and a two-dimensional image of the aircraft being inspected. Many times the location of discrepancies is identified by marking the surface with a grease pen or noting distances from physical aircraft references on a two-dimensional image. , e.g., structural frame and rivets.
The IETMs need to interact with a three-dimensional model of the aircraft and a way of pointing to a descrepancy that marks the location and description of the discrepancy on a virtual "space sticky" attached exactly to the location where the descrepancy was discovered.
The goal of repairs is to fix discrepancies in an system identified during an inspection. Some mobile systems provide IETM maintenance procedures viewed on a pen-based computer "tablet" or in a Head Worn Display (HWD) attached to a wearable computer.
In certain maintenance situations, e.g., working in cramped spaces, the displays are not easily viewed.
During these situations, the IETMs need to have a mode where they can be "read" by the mobile computer and the instructions heard through ear phones by the maintenance technician carrying out the maintenance tasks.