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.
Decision Matrix
My decision matrix was used to compare my three strategies in what I believe to be their most important categories: Cost, Durability, Size, Strength, 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 Electric Catbox was my best strategy primarily from it's ease of use and overall good scores in Product lifespan and strength. This catbox should be easy operational and have enough power to be able to successfully push all cat waste to one trash location.
The Manual catbox was a close runner up to the electric catbox because of its durability and safety, however, it is justifynot very desirable when it comes to ease of use. The best trait of a catbox is one where you don't have to be primarily involved in the scooping at all
My last strategy was the handheld claw ment to scoop cat waste. This design is not very durable because fatigue from the constant pulling close and reopening will take its toll very quickly causing a low product lifespan and it is extremely inifficient for use. I believe this strategy would make scooping catboxes a challenge by navigating the longer pole stick and trying to pick up the cat waste with the claw.
For this design, a catscooper is set stationary out of the catbox way until promted. Once the box is activated the scooper arm will be lowered into the circular bowl, where the bowl will then turn allowing sand to pass through and waste to be stuck in the scooper. The scooper will thenraise back into the main box and let the waste fall in the trash area.
| Functional Requirements | Design Parameters | Analysis | Resources | Risk | Countermeasures |
|---|---|---|---|---|---|
| Power supply to operate box | Amount of power must be enough to spin the base, and pull/lower the scooper portion | 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 |
| Device must not operate while cat is in box for safety reasons | a Timer, or sensor can be used to operate outside of bathroom hours | Auto timer set, kinematics equations can be used to determine time interval | Physics | The risk is setting an inappropraite time and having operation begin with cat in box | A countermeasure can be a sensor to halt operation or start it |
| 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 |
The idea for this concept is to just use straightforward force and power to push cat waste to a trash area and then return.
| Functional Requirements | Design Parameters | Analysis | Resources | Risk | Countermeasures |
|---|---|---|---|---|---|
| Power Supply | 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 |
| Timer | Must be able to clean box at appropriate time intervals or manually | Auto run every 2hours and have adjustable timer | Frequency of how often cats use the bathroom | The device may start when cat is using the box | Input a movement sensor to detect when cat is present |
| 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 |
The purpose of this concept is a rotating dome that separates the cat litter from the waste as it rotates, and then secures the cat litter while finally letting the waste drop out into the bottom feeder. Then the catbox rotates back so the sand is available for the cat.
| 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 rotate the circular dome down and then back, potentially trap cat inside | Coutermeasure is to always have the dome rotate so there is an open hole for escape, Provide more energy/power than required roughly 2W |
| 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 |
| Must be able to rotate freely enough | Torque must be strong enough to turn the dome | T=rFsintheta | Statics | If there is not enough Torque power the dome will not rotate | Supply more Force/Energy into the catbox for more torque. |
Gantt Chart
Activities:
10/21 Design Matrix 4pm-5pm
10/21 Gantt Chart: 5pm-7pm
10/21 Design strategies: 7-9pm
10/21 FRDPARRC Charts: 11pm-1am
Lessons Learned:
I learned how to think more creative because I had a really hard time thinking of 3 extremely similar concepts. I also learned how to make a Decision matrix.
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!