Problem Statement: The purpose of the design is to be an easy operation, or automated, cat box that gathers is capable of moving up to 3lbs of waste into a set trash area.
Assumptions: The design for the litter box should eliminate the need for using a hand-held scooper and needing to put cat waste away after each scoop.
My decision matrix was used to compare my three strategies in what I believe to be their most important categories: Cost, Durability, Size, Safety, Ease of Use, and Product Life span. I compared the values using a weight and point scoring system for each component and developing a score to find which strategy to choose
My Concept 2 was my best primarily from it's ease of use and overall excellent scores in Safety and Cost and Ease of Use. This catbox should be easy operational and have enough power to be able to successfully push all cat waste to one trash location.
Concept 1 was a close runner up to the because of itsease of use and size. I really like how automatic the catbox is, but I feel there are too many moving components that can cause early failure.
Concept 3 scored the lowest. Although it is very safe and easy to use, this product his high in cost by how intellectually advanced it is. Also the size would be much larger compared to the other boxes due to the fact it needs a dome high enough for a cat to get inside.
The functional requirement I will be focusing on for my modules is the ability to move the mesh wall back and forth within the litter box.
For this module, I created one way the cat scooper can move back and forth through the box to scoop. The concept is to be able to be pushed back and forth within the inside chamber area. There is one degree of freedom
| Functional Requirements | Design Parameters | Analysis | Resources | Risk | Countermeasures |
|---|---|---|---|---|---|
| Must have some form of power | Amount of power must be enough to push/pull scooper gate back and forth | P=fd, P=W/t, W=.5I(w)^2, t=60s | Physics | The risk of not having enough power is that waste may be left in the box if there is not enough output to fulfill the entire operation | Have an excess amount of power supplied, 1-2Watts is more than enough for operation |
| Gate must not flip around | Make the mesh gate must operate solely up and down when pushing | W=mg | Physics | The risk is having the gate just brush over the cat waste and not actually grab it | A countermeasure can be to increase the overall weight so it won't flip over |
For this module I tried a conveyer-belt design that as the belt rotates around it will bring the cat scooper mesh wall back and forth inside the litter box. There is one degree of freedom.
| Functional Requirements | Design Parameters | Analysis | Resources | Risk | Countermeasures |
|---|---|---|---|---|---|
| Power Supply to operate belt | Must be able to work when engaged | P=W/t, P=IV | Basic E | Must not be dangerous for cat | Cordless, Runs on batteries, Able to supply 11mW of power given .323J if operating under 30s. Enough power to complete .323J of work for a full rotation | Must be able to have strong rotation of bowl so all waste can be collected | Torque needs enough twisting force for full operation | T=rFsintheta | Statics | All waste may not be collected if rotation cannot be performed | Supply more energy/force for more torque capabilities, so box needs a minimum force of .5-1N |
| Sturdy/Strong | Must be able to push all cat waste out of box on it's own | W=fd, F=ma | Physics | The mesh scooping panel can get stuck on cat waste | Input a strong motor and supportive features to ensure the mesh wall stays upright while pushing up to 1kg of waste. |
| Mesh panel | Must be able to only push cat waste from box and not empty out the cat litter contents without breaking | mesh stress=F/A | solids | mesh can break | thicker/stronger mesh to ensure it is strong enough to push through cat box |
This module I believe to be the best module in the ways that a lead screw would be utilized in order to move the inside walls back and forth in the box. It would be very easy to add power and automation into this design. There is 2 degrees of freedom.
| Functional Requirements | Design Parameters | Analysis | Resources | Risk | Countermeasures |
|---|---|---|---|---|---|
| Power | Must be able to work when engaged | P=W/t, W=.5Iw^2, I=.5mr^2 | Physics and rotation | The risk of this design is not having enough force/power to fully go back and forth with the mesh panel in the box | Coutermeasure is to always provide more energy/power than required roughly 2W |
| Lead Screw | Screw is used as a basis for where the power gets supplied to move the mesh gate back and forth | T=rFsintheta | Statics | All waste may not be collected if full cycle cannot be performed | Supply more energy/force for more torque capabilities, so box needs a minimum force of .5-1N |
| Strength/Durability | The dome must be able to be strong enough to rotate and lift waste far enough so that it actually gets disposed of | W=Fd, W=t*theta | Physics | Waste may be too heavy and dome may not be able to do its full rotation | Provide excess energy to combat heavier waste, so if 2joules of energy needed, make it capable to provide 5joules of energy |
Gantt Chart
Activities:
11/11 Design Matrix 4pm-5pm
11/11 Gantt Chart: 5pm-7pm
11/11 Modules: 7-9pm
11/11 CAD: 7-9pm
11/11 FRDPARRC Tables: 11pm-1am
Lessons Learned:
I learned that these projects are starting to take more and more time and I need to work on my time management skills, I find myself always doing my assignments last minute and it is really hurting me. I also gained a little more experience with CAD modelling which I am not great at.
Comments to Advisees:
I like your project, However, there is still too much blank space in the excel sheets you have on your website, you can limit the range to make it easier to look at and for scrolling down the page. You have broken images on your website as well.
I like the layout of your website it is super easy to look at and navigate. Your concept images are well drawn and the equations were well thought out. I tell see you put alot of effort into thinking of new concepts for your design.Good job!