Team Vision for System-Level Design Phase
Our Plan For This PhaseDuring this phase, we hoped to gain an even better understanding of the problem through benchmarking and further discussion with our customer. We hoped to generate concept ideas and use feasibility testing to begin narrowing down our possibilities. We also plan to make updates to our documentation from the Problem Definition phase.
What We Actually AccomplishedWe developed multiple concepts for each of our required functions, as well as for our design as a whole. We began basic feasibility studies for specific aspects of our design, such as the seat, lift, and grab bars. Lastly, we continued our benchmarking and updated customer/engineering requirements.
Below is out Functional Decomposition chart. We strove to keep the functions general so that they didn't limit our concept ideas.
In order to better understand how our design needs to fit within ADA specifications, we did further research on ADA requirements.
To ensure that our design is able to be used by our target customer, we did some further on reach parameters by those in wheelchairs.
We also explored several different existing US patents to see if we could find devices that use functions that we desire to recreate in our preliminary designs.
Patent 5027446 is very similar to what we would like to replicate in terms of vertical lift function. It does lack side support and transfer aids.
Patent 5027446 is a stand-aid seat. While the lift functions differently from what we would like to see in our end-product, we like the way the seat is integrated into the frame and the side supports that the frame provides (though not adjustable).
We brainstormed concept ideas for each function. We listed these ideas on a whiteboard and images of our work are displayed below.
Feasibility: Prototyping, Analysis, Simulation
- Will our design compatible with multiple toilets?
- Preliminary Grab Bar Feasibility
For the grab bar feasibility, we first conducted a simple cantilever beam analysis in order to obtain the allowable stress on the bar from our max load. The analysis is documented below:
Here is the excel representation of Beam Analysis
Morphological Chart and Concept Selection
Link to full Morphological Chart here: Morphological Chart
The entire Pugh chart can be viewed here.
Designs and Flowcharts
Design Review Materialshttps://www.engineersedge.com/beam_bending/beam_bending1.htm
Plans for next phase
- Material testing and selection
- Research what materials will meet our design needs
- Understand machining capabilities offered at RIT
- Understand purchasing
- Order test materials