Boeing Wing Rib Workstation

The goal of this project is to develop a workstation that will facilitate all assembly of secondary components for a "generic" lower wing rib. Further considerations are laid out below and center around a movable workstation/tool system. The station will have modular options to eliminate redundant rib tools, and dynamic traits that will ease handling and assembly operations.

Background
Boeing is currently in the process of constructing a new airplane, the 777X. With a new design come new challenges. One in particular is the manufacturing and handling of the parts. The ribs in particular cannot be handled in the same way they have been with regards to preparing them for installation. Boeing has given us the task of constructing a tool/workstation that will make the assembly of components on the rib easy and efficient.

Deliverables

 * Concept sketches/CAD models and developed ideas of suitable frames to house the different size ribs.
 * Scale model prototype of a the complete workstation
 * Suggestion of necessary workstation features and appropriate positioning of those feautures.
 * Features include tool balancers and lighting

Ergonomics
Because the main purpose of this project is to facilitate easy handling and manipulation of large objects, ergonomics are a primary concern and focus. These considerations primarily center around the minor assembly that is to be performed on the wing component held by our tool. First and foremost we need to keep all assembly operations centered within the ergonomic strike or power zone. This region is identified by the vertical extent between the hip and top of the shoulder and approximately one to one and a half forearm lengths horizontally from the hip to shoulder line. The ideal vertical location is abeam to and one forearm length away from the elbow. This allows the technician or mechanic to support their tool or part with the least about of physical strain, using their body weight as the main force.

To quantify this area, anthropometric data tables were used to construct a diagram that shows how to calculate a universal strike zone for any rib size. The diagram uses the 95th percentile shoulder height for males and the 5th percentile elbow height for females to create the absolute bounds for our strike zone range. This means an ideal fit for 90 percent of possible user statures. The result of this analysis showed that the vertical movement that our machine must accommodate to fit this range would be close to the full vertical extent of the largest given rib. The overlap between male and female strike zones may ultimately be removed from this distance. Based on these findings we may have to reevaluate our strike zone goal since our calculations require almost 5 feet of vertical adjustability. Designs that use a variety of rib positioning to accommodate this full range may be a better alternative.



Repetitive injury from tool use is an issue that we will plan to address using a variety of tool counter balance or support devices. Finally safety considerations related to the placement of emergency stop buttons and protection of pinch or catch points related to any mechanical function of our eventual final design will need to be carefully considered.

Overview
The hoop is the most critical part of our design. It sustains the frame which will hold the ribs in place. It is the component that allows for rotation, thereby meeting the ergonomic and manufacturing standards necessary to work on the ribs in an effective manner. In a sense we have built the frame and all other components from the hoop out. While Boeing will have the capabilities to create such a product in a solid state, we have had to rely on a company that has bent metal bars into the proper shape. However, these bars are off somewhat and must also be welded at the ends. If the hoops are not identical and concentric to one and other, then our design will not function as intended. To fix this we will be using a fixture plate to trim and align them on a rotary table (as can be seen). This will then enable us to satisfy the design requirements.