Tolerance Management in a Semi-Automated and Collaborative Human-Robot Aircraft Riveting Process 2019-01-1373

Large aircraft sizes with high precision requirements combined with complex joining tasks are typical challenges for aircraft production. To increase competitiveness and effectiveness, the automation of such production processes seems a viable solution for companies in the aircraft sector. When implementing automation, in order to handle small batch sizes and high variation while adhering to tight tolerances, the production equipment must meet high quality standards and flexibility requirements.

To achieve the objectives above, tolerance management is essential: deviations are acceptable within limits, as long as they do not result in quality losses and expensive rework. For these reasons, all the interactions between the product, production process and production equipment used must be analyzed in detail. The importance of this analysis is evident in assembly where new technologies are used, such as (semi-)automation using Human-Robot-Collaboration. Despite its innovative value, this approach must be robust, within tolerances and have minimal deviations from the outset. However, current planning and optimization of deviations and tolerances lack properly developed methods and approaches.

This paper proposes a method for securing and achieving proper tolerance in assembly processes: characteristic trees and tolerance chains are simple methods to make tolerance management more effective and attractive. The method combination promotes understanding of interactions and communication between all those involved in the development of products and the associated processes.

The methods developed are validated using a semi-automated riveting process, with Human-Robot-Collaboration, to complete a joining process in the assembly of the aft section. In this scenario the pressure bulkhead is mounted to the section barrel by means of hundreds of rivets. The intention is to implement a semi-automated production process to improve ergonomics, increase process traceability and efficiency, and minimize rework while meeting tolerance requirements.