Weekly Progress Reports (see sidebar), the Gantt chart, and this Project Management page should be printed out before meetings with the sponsor and instructor.
All team members should be able to explain all items on the progress report.
Place a "*" at the beginning of the title of the active week Progress Report (see * in sidebar).
Project Objectives
Concisely list and prioritize the project objectives and constraints
High Priority Objectives
There is a mesh-like stiffness structure on the inside of the door that is meant to increase the door's moment of inertia and decrease the possibility of buckling due to the pressure difference between outside and inside environments. Our task is to determine the best stiffness design in order to use the least possible amount of material while obtaining the best pressure isolation.
Second Priority Objectives
As described by Collins’ Mechanical Design Engineer Mr. Johann Schrell, the market for business jets is composed exclusively of wealthy individuals, and their second priority to weight efficiency is the aesthetics of the product. The third priority of the target audience for these jets is how much the product costs.
Other desirable features include reducing the price to assemble or manufacture the product.
Other Constraints and Issues
Pressure Load: 13,283.84 lbf.
Pressure Gradient Across Door: 10.7 psi.
Equivalent Altitude for Interior Pressure: 4000 - 4500 ft.
Operation/Mechanism to open & close door similar to that of a Garage Door:
Door handle mechanisms have rods across the door: frame stiffness structure must have “pass through” holes in the design for the latch mechanism.
a Sliding mechanism allows the door to retract inside of baggage space in an upward motion.
4 pins served as part of door-locking mechanism.
Fittings: All force translates to the normal forces located at fittings.
At fittings: Normal forces are concentrated here.
16 locations, at both ends of a 4x4 extrusion mesh configuration.
Skin of Door: 0.036” thick.
Most prone to Buckling failure. Design accordingly.
Currently have 3-4 in. tall extrusions for mesh.
Consider Bending Conditions.
3x3 ft2, 121.5in2 (Surface Area of Baggage Door).
Current Door Skin Material: Aluminum 7050 (subject to change).
Other loads will not be considered since the only load that is important is the ultimate pressure difference between outside and inside.
WOW Design Solution
Ask what would their dream design solution would be like. You may not achieve this, but it is good to know what it would be like.
Ideally, the team aims to test all three possible door manufacturing methods Collins currently offers which are Aluminum multi-piece, Composite single-piece, and “Exotic Metal” 3D printed. Afterwards, The plan is to apply the most effective stiffness design to the most cost-efficient manufacturing design. For instance, if it were determined that Aluminum was the best material to use, considering both the resource waste and the expenses of piece-by-piece labor assembling process, then we could incorporate the fact that we’d use welding and screwing pieces together, in the design for our stiffness structure.
Risk Reduction Strategy
List areas of risk and strategy that will be used to eliminate risk really in the design process.
The main risk we are trying to reduce with this project is the possibility that the door structure cannot handle the pressure difference between the outside and inside environments and as a result buckle. Our team will develop several initial stiffness structure designs and a matrix system will be developed to determine the best five. From there each member will develop tests for each design to determine the optimal one with which we will run further tests and analyses.
We were advised to run all tests assuming the stiffness structure/door structure is a single solid piece. The reason is that it makes calculations slightly easier. If enough time and resources are within our reach, the team plans to investigate the effect of having things screwed/welded on.
Intermediate Milestones
Identifying meaningful intermediate milestones is a critical for effective project management. Together with your sponsor identify such milestones, and specify specific performance requirements you aim to meet at each milestone.
Collins Aerospace does not have a tight deadline at the end of which they need to deliver the optimal baggage door design, and thus they have made it very clear that the intermediate milestones are completely up to the team. We have already identified that there is an immediate need to start brainstorming mesh designs, so that we can find between ten and twenty that we think could work (X-shaped, O-shaped, tree-shaped, or others) that we will then cut down to the top 5, so we can run stress tests on them and start prototyping by the start of Spring Quarter in the first week of April.
Other milestones are: the beginning of prototyping with miniature models, full-scale prototyping, and final presentation.