Design and Development - Major Assignment (Design & Build Project)The major assignment is to design and build a mousetrap powered delivery device that can transport a payload to the top of a free standing pipe (see the illustration below) and drop it inside, whilst starting the device from a distance of 1.5m from the pipe. This is a group project to be completed with groups of 4 students (to be selected by students); please be sure that all students print their name on the coversheet with accompanying signature.
The device will be powered by an unmodified, single, off-the-shelf, snap-style mousetrap (supplied but lecturer) and the payload will consist of a small weight provided by the group (and will be weighed during the competition runs). The device must start on the ground, behind a line that is 1.5m from the centre of the pipe. The pole has a maximum height of 600mm and a small aluminium base.
Marks will be assigned to performance, based on a points system. Performance points are awarded according to the following equation, which is a function of the payload weight (grams) and the volume of your device in cubic centrimetres (calculated by the maximum width, length and height of your device):
Points = (Payload)2/√(Device Volume)
The payload weight is measured in grams and this is the weight of item that is dropped into the free standing pipe (i.e. does not include the device).
Please note the following:
- A single mousetrap will be supplied to each group
- There is no allowable modifications to the mousetrap spring
- The mousetrap spring is the ONLY power source for your device (i.e. no electrical power sources, no counterweights, etc.)
- The entire device must start from the ground, behind the line 1.5m from the pole.
- The maximum device setup time is 30seconds and the maximum dismantle time is 30seconds
- Only a single action can start your device
- There is no allowable rigid fastening to the ground (i.e. gluing, bolting, clamping, etc.)
The assignment deliverables for the Mousetrap Powered Payload Delivery are as follows:
1. Design document: A complete set of reports for the device parts and assembly: A design report that details:
- Product design specification (PDS)
- Different concepts and their evaluation
- Manufacturing details and why they are selected (including techniques and processes applied, off-the-shelf components, etc.). Also describe how these manufacturing techniques may vary for large volume production.
- Cost analysis (including a complete cost breakdown of your device)
An analysis report that covers:
- Strategy calculations
- Structural load calculations prior to stress analysis
- Stress and stiffness calculations
- Failure analysis calculations where applicable
SolidWorks 3D models (parts and assemblies) and a complete set of manufacturing drawings - fully dimensioned such that another device could be manufactured
2. Performance: In-class test of your group's device in the final lecture during your presentation. Marks will be awarded for the overall performance of your device based on the provided equation:
Points = (Payload)2/√(Device Volume)
Please read the following notes on performance mark allocation:
i. A complete and working device will achieve a minimum performance mark of 50%
ii. A performance mark between 50-100% will be scaled based on the highest and lowest performance points achieved
iii. A complete device that works unsuccessfully will achieve a minimum performance mark of 25%
iv. An incomplete device will be awarded a performance mark between 0-25% based on level of completion.
3. Project quality: Project quality mark is based on the overall report quality, such as grammar, referencing, presentation, etc.
4. Presentation: 5 minute (only) presentation during the final lecture of your group's Mousetrap Powered Elevator design.
Note: The written component of the entire design document should not exceed 40 pages, any content beyond this page limit will not be considered in the mark. This page limit excludes figures, SolidWorks illustrations, calculations and other non-text material.