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With the increasing requirements for intelligence in the field of aviation manufacturing, manual assembly can hardly adapt to the trend of future production. The purpose of this study is to realize the semi-automatic assembly of the movable airfoil by proposing a human-robot collaborative assembly strategy based on adaptive admittance control.

A logical judgment system for operating intentions is introduced in terms of different situations of the movements; hence, a human cognition-based adaptive admittance control method is developed to curb the damage of inertia; then virtual limit walls are raised on the periphery of the control model to ensure safety; finally, simulated and experimental comparisons with other admittance control methods are conducted to validate the proposed method.

The proposed method can save at least 28.8% of the time in the stopping phase which effectively compensates for inertia during the assembly process and has high robustness concerning data disturbances.

Due to the human-robot collaboration to achieve compliant assembly of movable airfoils can preserve human subjectivity while overcoming the physical limits of humans, which is of great significance to the investigation of intelligent aircraft assembly, the proposed method that reflects the user's naturalness and intuitiveness can not only enhance the stability and the flexibility of the manipulation, but also contribute to applications of industrial robots in the field of human-robot collaboration.

The purpose of this research is to explore the utility of autonomous transport across two independent airframe maintenance operations at a single location.

This study leveraged discrete event simulation that encompassed real-world conditions on a United States Air Force flight line. Though the Theory of Constraints (TOC) lens, a high-demand, human-controlled delivery asset is analyzed and the impact of introducing an autonomous rover delivery vehicle is assessed. The authors’ simulations explored varying numbers and networks of rovers as alternative sources of delivery and evaluated these resources’ impact against current flight line operations.

This research indicates that the addition of five autonomous rovers can significantly reduce daily expediter delivery tasks, which results in additional expertise necessary to manage and execute flight line operations. The authors assert that this relief would translate into enhancements in aircraft mission capable rates, which could increase overall transport capacity and cascade into faster cargo delivery times, systemwide. By extension, the authors suggest overall inventory management could be improved through reduction in transportation shipping time variance, which enhances the Department of Defense’s overall supply chain resilience posture.

When compared against existing practices, this novel research provides insight into actual flight line movement and the potential benefits of an alternative autonomous delivery system. Additionally, the research measures the potential savings in the workforce and vehicle use that exceeds the cost of the rovers and their employment.

Aircraft structures are mainly connected by riveting joints, whose quality and mechanical performance are directly determined by vertical accuracy of riveting holes. This paper proposed a combined vertical accuracy compensation method for drilling and riveting of aircraft panels with great variable curvatures.

The vertical accuracy compensation method combines online and offline compensation categories in a robot riveting and drilling system. The former category based on laser ranging is aimed to correct the vertical error between actual and theoretical riveting positions, and the latter based on model curvature is used to correct the vertical error caused by the approximate plane fitting in variable-curvature panels.

The vertical accuracy compensation method is applied in an automatic robot drilling and riveting system. The result reveals that the vertical accuracy error of drilling and riveting is within 0.4°, which meets the requirements of the vertical accuracy in aircraft assembly.

The proposed method is suitable for improving the vertical accuracy of drilling and riveting on panels or skins of aerospace products with great variable curvatures without introducing extra measuring sensors.

The purpose of this paper is to examine an issue of critical importance to America’s national security. The Civil Reserve Air Fleet (CRAF) is a public/private partnership between US air carriers and the Department of Defense (DOD) for the provision of contingency airlift services to the military in times of national need. Formed in 1951, the CRAF has only been activated twice, but it has continued to be a source of emergency air transportation should the nation require resources beyond those available from the US Air Force. Sweeping changes occurring in global trade, commercial aviation, national defense policy and foreign relations suggest that changes will be needed to maintain the CRAF as a strategic defense transportation resource.

This paper examines the long-standing national policy of relying on commercial interests to provide contingency transportation to the DOD in wartime. The CRAF will be singled out for closer examination in light of environmental changes occurring in the airline industry, international trade and global threats to the nation. The purpose of this analysis is to then assess the partnership’s ability to remain relevant in an uncertain future.

First, commercial cargo aircraft are downsizing thereby becoming less useful to the DOD. Second, there is no new wide-body military airlifter on the horizon. Third, threats from hostile nations are becoming more indirect and subtle, requiring planners to think “outside the box” when assessing the need for strategic airlift over the next 20-50 years.

The CRAF has not fundamentally changed since its inception in 1951. The time has come to reexamine the partnership to ensure that it remains America’s emergency lifeline.