Laptop chill pad
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- | [[Image:LaptopChillPad_Top_View.JPG|right|450px]] | + | [[Image:LaptopChillPad_Top_View.JPG|thumb|right|450px|Logitech - N200 Laptop Cooling Pad]] |
<br> <br> <br> <br> | <br> <br> <br> <br> | ||
==Executive Summary== | ==Executive Summary== | ||
We have completed a preliminary design study of the Logitech Cooling Pad N200. Initially, group discussions included problems with the existing model as well as possible and feasible improvements. With these in mind, we conducted a product dissection study. Our analysis of the design consisted of four approaches: design for manufacturing, design for assembly, failure modes and effects, and design for environment. | We have completed a preliminary design study of the Logitech Cooling Pad N200. Initially, group discussions included problems with the existing model as well as possible and feasible improvements. With these in mind, we conducted a product dissection study. Our analysis of the design consisted of four approaches: design for manufacturing, design for assembly, failure modes and effects, and design for environment. | ||
<br><br> | <br><br> | ||
- | After conducting the design analysis for manufacturing and assembly, we can conclude that | + | After conducting the design analysis for manufacturing and assembly, we can conclude that for the most part, the product has been designed for efficient manufacturing and assembly. Few possible design improvements linger, but determining their actual effectiveness will require further study on product use and specific manufacturing and assembly methods. |
+ | <br><br> | ||
+ | Our design for environment analysis showed that the production of our product would result in a minuscule CO2 tax, less than 2% of the retail value. Nearly 90% of our greenhouse gas emissions came from the laptop manufacturing and electricity production. Our product saves the user from replacing their laptop battery once throughout the product's lifespan which would cause the CO2 tax to be lowered. | ||
+ | <br><br> | ||
+ | Failure modes and effects analysis showed that the product is not likely to experience severe, commonly occurring and difficult to detect modes of failure. The biggest concerns are with the USB cord, specifically a break in the inner wires. Introducing a retractable element to the pad design would leaving no slack in the cord, lowering the occurrence of this failure. In general though, most failures can be fixed with simple design changes, allowing us to focus more on environmental and cost considerations. | ||
+ | <br><br> | ||
+ | After conducting the design analysis, we concluded that | ||
+ | the product was designed to optimize manufacturing and assembly. | ||
+ | We decided that our design would be more focused on the product performance | ||
+ | than on the manufacturing and assembly aspect. Our improvements are going | ||
+ | to focus mostly on the usage phase. Improving product performance would have | ||
+ | a significant effect on the battery life. | ||
- | + | <br> | |
==Stakeholders Information== | ==Stakeholders Information== | ||
Line 13: | Line 24: | ||
===Customer=== | ===Customer=== | ||
The primary consumers for chill pads are users who intensively use their laptops such as gamers and most college students. College students are much more likely to have laptop computers and laptops typically overheat when the user is playing games. Because the chill pad would be used mostly in dormitory settings, portability is not a main priority. Rather, durability and effectiveness are more important for the target consumer. | The primary consumers for chill pads are users who intensively use their laptops such as gamers and most college students. College students are much more likely to have laptop computers and laptops typically overheat when the user is playing games. Because the chill pad would be used mostly in dormitory settings, portability is not a main priority. Rather, durability and effectiveness are more important for the target consumer. | ||
+ | <br><br> | ||
Customer Needs: | Customer Needs: | ||
*Relatively cheap- under $50 | *Relatively cheap- under $50 | ||
Line 31: | Line 43: | ||
===Retailer=== | ===Retailer=== | ||
The primary retailers are those who directly sell the product to consumers, varying from electronic stores to online retailers. They can be identified as stores that primarily sell technology-related products. These stores would prefer a slick design as well as product performance to attract younger, more tech savvy consumers. | The primary retailers are those who directly sell the product to consumers, varying from electronic stores to online retailers. They can be identified as stores that primarily sell technology-related products. These stores would prefer a slick design as well as product performance to attract younger, more tech savvy consumers. | ||
+ | <br> <br> | ||
Retailer Needs: | Retailer Needs: | ||
*Good presentation | *Good presentation | ||
Line 41: | Line 54: | ||
===Manufacturer=== | ===Manufacturer=== | ||
Manufacturers are responsible for mass production of products. Therefore they would value low production costs.This means lower costs for raw materials, simple assembly, among others. | Manufacturers are responsible for mass production of products. Therefore they would value low production costs.This means lower costs for raw materials, simple assembly, among others. | ||
+ | <br> <br> | ||
Manufacturer Needs: | Manufacturer Needs: | ||
*Low production cost | *Low production cost | ||
Line 54: | Line 68: | ||
Shipping/transport stakeholders are primarily commercial delivery companies. They would benefit from lighter, easily packaged products, and small manageable packages. | Shipping/transport stakeholders are primarily commercial delivery companies. They would benefit from lighter, easily packaged products, and small manageable packages. | ||
+ | <br> <br> | ||
Shipper Needs: | Shipper Needs: | ||
*Durable product | *Durable product | ||
Line 60: | Line 75: | ||
<br> | <br> | ||
- | == | + | ==User Study== |
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | == | + | ===Usage=== |
+ | Different chill pads have variations in their use. However the basic steps are as follows:<br> | ||
+ | 1. Place chill pad on surface <br> | ||
+ | 2. Place laptop on chill pad<br> | ||
+ | 3. Plug chill pad into laptop<br> | ||
+ | |||
+ | <br> | ||
+ | The specific steps for the N200 Chill Pad were as follows: <br> | ||
+ | [[Image:LaptopChillPad_UserInstructions.jpg|thumb|center|600px|User Instructions for Logitech N200]] | ||
+ | <br> | ||
+ | These are the instructions for another chill pad that we tested. | ||
+ | [[Image:LaptopChillPad_UserInstruction3.jpg|thumb|center|800px|User Instructions for Coldplayer]] | ||
+ | <br> | ||
+ | |||
+ | ===Effects=== | ||
+ | An experiment was conducted that assessed the effects of the chill pad on the temperature of a laptop. The stages of the experiment are as follows: <br> | ||
+ | 1.Ran several programs on a computer(SolidWorks, a graphic-intensive game, and youtube video) with the chill pad on (apprx 12 mins) <br> | ||
+ | 2.Continued running same programs on computer with chill pad off (apprx 8 mins) <br> | ||
+ | 3.Continued running same programs on laptop with chill pad on (apprx 3 mins) <br> | ||
+ | <br> <br> | ||
+ | The temperatures of the internal components (core 1 and 2 of a dual core computer processor) were measured during these three phases, and the results are graphed below: <br> <br> | ||
+ | [[Image:LaptopChillPad Temperature analysis.png|thumb|center|300px|Effects of Chill Pad on Laptop Temperature]] | ||
+ | The laptop had many programs running simultaneously which in turn increased the temperature within the laptop. After reaching the steady state without the chill pad, the chill pad was then turned on. The chill pad had a significant role in cooling the laptop because after the chill pad was turned on, the temperature of the cores on the computer dropped 20 degrees. | ||
+ | <br> | ||
+ | [[Image:LaptopChillPad_Batterylifetable.JPG|thumb|center|500px|Battery Life Table: See Reference #1 Below]] | ||
+ | <br> | ||
+ | This table shows the results of high temperature on batteries. As can be seen, subjecting the laptop to high temperatures significantly and permanently decreases the battery life. During high activity, laptop interiors can reach temperatures up to 180 degrees Fahrenheit. | ||
+ | |||
+ | ==Design For Manufacturing and Assembly== | ||
===Design for Manufacturing=== | ===Design for Manufacturing=== | ||
- | The competitor’s product has been designed well with respect to manufacturability. The product has a low complexity as well as a part count that matches | + | The competitor’s product has been designed well with respect to manufacturability, especially in high volumes. The product has a low complexity as well as a part count that matches its level of complexity. All of the plastic parts are injection molded and have been designed well with respect to their manufacturing process. For instance, each part has uniform wall thickness and has ribs and other strengthening features with good dimensions. In addition, the manufacturer made new parts for parts with different geometry in order to keep the molds simple. Another good feature is that the coloring of parts can be incorporated into the molding process, thereby cutting down on the steps needed to manufacture the product. Once the parts are molded, they do not need secondary operations, except for painting on the Logitech logo on the front of the chillpad. |
+ | Another well designed aspect is the use of rubber spacers in between the top and bottom cover. One of its main uses is that it allows for lower requirements on tolerance of the molds, thus making the molds cheaper. | ||
+ | The most number of parts comes from the number of screws. Although this could be lowered by changing from screws to a molded in, snap-fit feature, using screws allows the part to be assembled easier, allows for the ability to open the product without breaking it, and keeps the mold simpler and cheaper. However, instead of having different screws, the screws can be standardized for all uses. | ||
+ | In summary, the competitor’s product has been designed well for manufacturing and there is little room for improvement in this area. | ||
+ | <br> <br> | ||
+ | '''Well-Designed''' | ||
+ | *Relatively low part number and simple parts | ||
+ | *Mostly all parts injection molded | ||
+ | **Plastic material, easy to work with | ||
+ | **allows color to be built in, instead of painting | ||
+ | **Parts designed well for molding: same wall thicknesses, ribs and strengthening features are good dimensions | ||
+ | *Areas of the part with different geometries were made into different parts, | ||
+ | **To keep mold simple | ||
+ | *Used rubber stoppers between parts to account for tolerances | ||
+ | **Lower tolerance allowed | ||
+ | |||
+ | '''Areas of Improvements''' | ||
+ | *Different screws, standardize them | ||
+ | <br> | ||
+ | |||
===Design for Assembly=== | ===Design for Assembly=== | ||
- | Although the design for assembly can be improved on, most aspects of the design have been optimized to enable an easy, cheap assembly process. As for major improvements, the fan containment shell could be joined with the bottom body piece as one piece. There could be certain problems regarding the manufacturing process, but it would improve the design for assembly. In addition, the fan and shell casing components could be a subassembly that could be manufactured separately. The Logitech logo piece is unnecessary and just adds to the complexity of the assembly. Lastly, joining the felt to the bottom piece provides an assembly complexity as it may require multiple assembly directions or manual assembly. As for minor improvements, screws could be replaced with snap-fit designs and the screws necessary could be standardized. As for the current design, the elastic spacers between two parts are a useful inclusion for variable manufacturing tolerances. Another noteworthy design decision was the fan subassembly. The fan component | + | Although the design for assembly can be improved on, most aspects of the design have been optimized to enable an easy, cheap assembly process. As for major improvements, the fan containment shell could be joined with the bottom body piece as one piece. There could be certain problems regarding the manufacturing process, but it would improve the design for assembly. In addition, the fan and shell casing components could be a subassembly that could be manufactured separately. The Logitech logo piece is unnecessary and just adds to the complexity of the assembly. Lastly, joining the felt to the bottom piece provides an assembly complexity as it may require multiple assembly directions or manual assembly. As for minor improvements, screws could be replaced with snap-fit designs and the screws necessary could be standardized. As for the current design, the elastic spacers between two parts are a useful inclusion for variable manufacturing tolerances. Another noteworthy design decision was the fan subassembly. The fan component contained a circular magnet, and it rested over a chip with four copper coils, a simple electrical motor with no rotating shafts or additional components to bog down the assembly and manufacturing processes. The general assembly process seems unambiguous and the assembly surfaces are kept to a decent minimum. |
- | ''' | + | '''Well-Designed''' |
*Assembly directionality is mostly unambiguous and simple | *Assembly directionality is mostly unambiguous and simple | ||
*Fan subassembly is designed to function without rotating shaft | *Fan subassembly is designed to function without rotating shaft | ||
*Elastic spacers are used to fit pieces with variable manufacturing tolerances | *Elastic spacers are used to fit pieces with variable manufacturing tolerances | ||
- | ''' | + | '''Areas of Improvement''' |
*Fan and casing could be subassembly | *Fan and casing could be subassembly | ||
*Rubber Logitech piece is unnecessary and just adds to manufacturing and assembly complexity | *Rubber Logitech piece is unnecessary and just adds to manufacturing and assembly complexity | ||
*Attaching felt onto plastic piece provides assembly complexity | *Attaching felt onto plastic piece provides assembly complexity | ||
+ | <br> | ||
==FMEA (Failure Mode and Effects Analysis)== | ==FMEA (Failure Mode and Effects Analysis)== | ||
- | |||
===Table=== | ===Table=== | ||
{| class="wikitable" border="1" cellspacing="0" align="center" style="text-align:center" | {| class="wikitable" border="1" cellspacing="0" align="center" style="text-align:center" | ||
Line 128: | Line 182: | ||
|Screws - Holds Assembly Together||Loosening|| Assembly falling apart || 4 || Overuse, Fatigue || 2 || Testing of regular use || 3 || 24 || None (Out of Designer Control) | |Screws - Holds Assembly Together||Loosening|| Assembly falling apart || 4 || Overuse, Fatigue || 2 || Testing of regular use || 3 || 24 || None (Out of Designer Control) | ||
|- | |- | ||
- | |Rubber stoppers - Stops the computer from slipping || Disconnects from grill || Laptop slips off chill pad || || || || || || || Put stronger grips on | + | |Rubber stoppers - Stops the computer from slipping || Disconnects from grill || Laptop slips off chill pad || 4 || Overuse, designed too loosely || 3 || Load and cyclic testing on stoppers || 2 || 24 || Put stronger grips on rubber stopper or adhere them differently |
|- | |- | ||
- | |Rubber spacers - Pushes apart the top and bottom cover || | + | |Rubber spacers - Pushes apart the top and bottom cover || Rubber tears || Top and bottom are not tightly connected everywhere || 4 || Overuse, weak rubber material || 2 || Cyclic testing on the assembly with spacers || 4 || 32 || Add more support to lessen the load on each spacer |
|} | |} | ||
+ | ===Results=== | ||
+ | Across the board, the detectability scores for the device’s failure modes are very low, that is, anything that goes wrong with the device will be quickly and easily spotted by the user. The highest RPN value is associated with the mode of failure wherein the USB cord stops transmitting power due to damaged wires inside. This is a critical failure mode because it compromises the functionality of the whole device, the part is not easily replaceable, and USB wires are not typically very strong. To combat this potential failure, we propose a mechanism to retract the cord, which would avoid situations where slack in the cord makes it susceptible to damage. Another major concern from the analysis above is a tear in the rubber spacers between the top and bottom plates of the chill pad. More in depth analysis should be done to test whether the material of the rubber is strong enough to withstand overuse or if more support points should be added to better distribute the load. In general though, these failure modes have mostly low scores, and we do not expect them to get in the way of improving on the product’s design for cost effectiveness, lessening environmental impact, and other factors more constraining than failure mode analysis. | ||
==Design for Environment== | ==Design for Environment== | ||
+ | As companies and engineers are becoming more aware of how their products impact the environment, consideration of this has been added to the product design process. As global warming becomes a more widely recognized fact, the reduction of greenhouses gas emissions has become important. With a possibility of a federal tax on the emissions of greenhouse gases($30/mt), it is necessary to conduct a study on how this tax would effect a laptop chill pad. | ||
+ | ===Production=== | ||
+ | Greenhouse Gases | ||
+ | Using the EIOLCA model (See reference #3 at the bottom) we were able to determine an estimate on the total amount of CO2 the production phase of a laptop chill pad would produce. We ran the model using the small electrical appliance manufacturing sector(#335210) with an input of $1 million. As seen on the chart on the left 570mt of CO2 were emitted. Scaling this to the emissions for the manufacturing of a single laptop chill pad costing $40 we found that 0.0228mt of CO2 are released. A $30/mt tax would cost a company an additional $0.68 per laptop which is 1.7% the total cost. | ||
- | + | [[Image:GHGE1a.PNG|thumb|center|500px|CO2 Emissions for the Manufacturing of the Chill Pad]][[Image:GHGE1b.PNG|thumb|center|500px|Breakdown of the Contributing Factors]] | |
+ | <br> | ||
+ | Economic Activity | ||
+ | An analysis of the economic activity shows that per $1 million spent on the retail value of the product, $2.18 million is spent in creating it. | ||
+ | |||
+ | [[Image:EC1a.PNG|thumb|center|500px|Economic Activity for the Manufacturing of the Chill Pad]][[Image:EC1b.PNG|thumb|center|500px|Breakdown of the Contributing Factors]] | ||
===Use=== | ===Use=== | ||
+ | There are two components that are used in conjunction with our product. The first and most obvious is a laptop that the chill pad is specifically designed for. The second component is the electricity that is needed to power the laptop while it is in use. | ||
+ | |||
+ | '''Laptop''' | ||
+ | |||
+ | Greenhouse Gases | ||
+ | |||
+ | The CO2 emissions that are involved with the manufacturing of a laptop are needed. The EIOLCA model was used with an input of $1 million to determine the amount of CO2 emitted. For a laptop we choose to use the electronic computer manufacturing sector, #334111. A total of 284 mt of CO2 were produced and when scaled to the production of a single laptop(~$1000) we see that 0.28mt of CO2 are emitted. With a tax of $30/mt this equates to $8.52 or 0.852% the total cost. | ||
+ | |||
+ | [[Image:GHGE2a.PNG||thumb|center|500px|CO2 Emissions for the Manufacturing of a Laptop]][[Image:GHGE2b.PNG||thumb|center|500px|Breakdown of the Contributing Factors]] | ||
+ | |||
+ | '''Electricity Production''' | ||
+ | |||
+ | Greenhouse Gases | ||
+ | |||
+ | The production of the electricity needed to power the laptop emits C02. As done previously the EIOLCA model is used per $1 million to compute an estimation. The power generation and supply sector, #221100, was run to determine that 9370mt of CO2 were emitted per $1 million. A few assumptions were made to determine the impact for the chill pad's life cycle: | ||
+ | |||
+ | 1. An average laptop uses 70 watts per hour | ||
+ | |||
+ | 2. An average user will use their laptop for 2.5 hours a day | ||
+ | |||
+ | 3. The chill pad has a life cycle of 3 years. | ||
+ | |||
+ | 4. 1 kWh costs $0.112 (See Reference #2) | ||
+ | |||
+ | Using these parameters we estimate that 191.625 kWh are consumed at a cost of $21.46. Thus per life cycle 0.2010802mt of CO2 are emitted at a cost of $6.03. | ||
+ | |||
+ | [[Image:GHGE3a.PNG||thumb|center|500px|CO2 Emissions for the Electricity Production]][[Image:GHGE3b.PNG||thumb|center|500px|Breakdown of the Contributing Factors]] | ||
+ | |||
+ | ====Battery==== | ||
+ | |||
+ | We assumed that a laptop battery lasts 1.5-3 years(See References #4 & #5) and thus the consumer would replace the battery once throughout the chill pad's lifespan. Analyzing the emissions in producing a single laptop battery shows that 0.05mt are emitted. With the CO2 tax this would equate to $1.56. However our analysis in the User Study section illustrates the chill pad has the potential to cool the laptop enough to allow the battery to last the duration of the chill pad's lifespan. | ||
+ | |||
+ | [[Image:GHGE4a.PNG||thumb|center|500px|CO2 Emissions for the Manufacturing of a Laptop Battery]][[Image:GHGE4b.PNG||thumb|center|500px|Breakdown of the Contributing Factors]] | ||
+ | |||
+ | |||
+ | |||
+ | <br> | ||
+ | |||
+ | ===Conclusion=== | ||
+ | |||
+ | The summary for the analysis of the environmental impact from production and usage phases are displayed in the table below. The pie graph shows the breakdown of how each component contributes to the overall CO2 tax that we would incur. The important takeaway is that the production phase only accounts for $% of the total CO2 tax. The laptop manufacturing and electricity production account for the majority of the tax, combining for 87%. While the manufacturing of a laptop battery is only a tenth of the overall tax, it has the possibility to be negated. Early evidence shows that the chill pad has the possibility to keep the laptop at a cool enough temperature that it will extend the battery's lifespan. If this longer lifespan can last the duration of the chill pad's lifespan then the consumer would not have to purchase a new battery and would lower our CO2 tax. | ||
+ | <br> | ||
+ | [[Image:Table1.PNG|thumb|center|700px|Summary of EIO-LCA Results]] | ||
+ | <br> | ||
+ | |||
+ | [[Image:PieChart.PNG|thumb|center|700px|Breakdown of Each Contributor to the CO2 Tax]] | ||
+ | |||
+ | <br> | ||
==Bill of Materials== | ==Bill of Materials== | ||
Line 164: | Line 277: | ||
| Top Cover | | Top Cover | ||
| 1 | | 1 | ||
- | | | + | | 262.2 |
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Connects to the top grill and bottom cover. Protects inner workings. | | Connects to the top grill and bottom cover. Protects inner workings. | ||
| [[Image:LaptopChillPad_Top_Cover.JPG|thumb|center|100px|Top Cover]] | | [[Image:LaptopChillPad_Top_Cover.JPG|thumb|center|100px|Top Cover]] | ||
Line 173: | Line 286: | ||
| Top Grill | | Top Grill | ||
| 1 | | 1 | ||
- | | | + | | 170 |
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Connects to the top cover. Protects the fan and allows fan blown air to go through. | | Connects to the top cover. Protects the fan and allows fan blown air to go through. | ||
- | | | + | | [[Image:LaptopChillPad_Grill.jpg|thumb|center|100px|Grill]] |
|- | |- | ||
| 3 | | 3 | ||
- | | | + | | Screws |
| 5 | | 5 | ||
- | | | + | | < 1 |
| Steel | | Steel | ||
- | | | + | | Purchased |
| Connects the top cover to the bottom cover. | | Connects the top cover to the bottom cover. | ||
- | | | + | | [[Image:LaptopChillPad_TopBottomScrew.JPG|thumb|center|100px|Screw]] |
|- | |- | ||
| 4 | | 4 | ||
Line 193: | Line 306: | ||
| .25 | | .25 | ||
| Rubber | | Rubber | ||
- | | Molding | + | | Injection Molding |
| Connects the fan assembly to the top cover. | | Connects the fan assembly to the top cover. | ||
| [[Image:LaptopChillPad_Rubber_Screws.JPG|thumb|center|100px|Rubber Screw]] | | [[Image:LaptopChillPad_Rubber_Screws.JPG|thumb|center|100px|Rubber Screw]] | ||
Line 200: | Line 313: | ||
| Fan Casing | | Fan Casing | ||
| 1 | | 1 | ||
- | | | + | | 16.5 |
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Connects to the top cover and the fan. | | Connects to the top cover and the fan. | ||
- | | | + | | [[Image:LaptopChillPad_Fan_Casing.jpg|thumb|center|100px|Fan Casing]] |
|- | |- | ||
| 6 | | 6 | ||
Line 211: | Line 324: | ||
| 25 | | 25 | ||
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Spins and blows air through the grill. | | Spins and blows air through the grill. | ||
| [[Image:LaptopChillPad_Fan.JPG|thumb|center|100px|Fan]] | | [[Image:LaptopChillPad_Fan.JPG|thumb|center|100px|Fan]] | ||
Line 218: | Line 331: | ||
| Motor | | Motor | ||
| 1 | | 1 | ||
- | | | + | | 7.4 |
- | | | + | | Various |
- | | | + | | Purchased |
| Connects to the fan. Spins the fan. | | Connects to the fan. Spins the fan. | ||
| [[Image:LaptopChillPad_Motor.JPG|thumb|center|100px|Motor]] | | [[Image:LaptopChillPad_Motor.JPG|thumb|center|100px|Motor]] | ||
Line 229: | Line 342: | ||
| 40 | | 40 | ||
| Felt | | Felt | ||
- | | | + | | Purchased |
| Glued to the bottom cover. Provides soft interface between the user and product. | | Glued to the bottom cover. Provides soft interface between the user and product. | ||
| [[Image:LaptopChillPad_Felt.JPG|thumb|center|100px|Felt]] | | [[Image:LaptopChillPad_Felt.JPG|thumb|center|100px|Felt]] | ||
Line 238: | Line 351: | ||
| 186 | | 186 | ||
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Connects to the top cover and protects the inner workings. Provides a base for the product. | | Connects to the top cover and protects the inner workings. Provides a base for the product. | ||
| [[Image:LaptopChillPad_Bottom_cover.JPG|100px|thumb|center|Bottom Cover]] | | [[Image:LaptopChillPad_Bottom_cover.JPG|100px|thumb|center|Bottom Cover]] | ||
Line 247: | Line 360: | ||
| 81 | | 81 | ||
| Plastic | | Plastic | ||
- | | Molding | + | | Injection Molding |
| Connects to the bottom cover. Allows air to flow into the chillpad. | | Connects to the bottom cover. Allows air to flow into the chillpad. | ||
| [[Image:LaptopChillPad_Air_Intake.JPG|100px|thumb|center|Air Intake]] | | [[Image:LaptopChillPad_Air_Intake.JPG|100px|thumb|center|Air Intake]] | ||
|- | |- | ||
| 11 | | 11 | ||
- | | Screws | + | | Small Screws |
| 3 | | 3 | ||
- | | | + | | < .1 |
| Steel | | Steel | ||
- | | | + | | Purchased |
| Connects the air intake to the top cover. | | Connects the air intake to the top cover. | ||
- | | | + | | [[Image:LaptopChillPad_Air_Intake_Screws.jpg|thumb|center|100px|Small Screw]] |
|- | |- | ||
| 12 | | 12 | ||
Line 265: | Line 378: | ||
| .25 each | | .25 each | ||
| Rubber | | Rubber | ||
- | | Molding | + | | Injection Molding |
| Pushes on the top and bottom cover to provide a space in between. | | Pushes on the top and bottom cover to provide a space in between. | ||
| [[Image:LaptopChillPad_Rubber_Spacer.JPG|thumb|center|100px|Rubber Spacer]] | | [[Image:LaptopChillPad_Rubber_Spacer.JPG|thumb|center|100px|Rubber Spacer]] | ||
Line 274: | Line 387: | ||
| 12 each | | 12 each | ||
| Rubber | | Rubber | ||
- | | Molding | + | | Injection Molding |
| Connects to the top grill. Provides increased friction between the laptop and chillpad to keep it from moving. | | Connects to the top grill. Provides increased friction between the laptop and chillpad to keep it from moving. | ||
| [[Image:LaptopChillPad_Rubber_Stopper.JPG|thumb|center|100px|Rubber Stopper]] | | [[Image:LaptopChillPad_Rubber_Stopper.JPG|thumb|center|100px|Rubber Stopper]] | ||
Line 281: | Line 394: | ||
| USB Connector | | USB Connector | ||
| 1 | | 1 | ||
- | | | + | | 4.3 |
- | | | + | | Various |
- | | | + | | Purchased |
| Connects the chillpad to the computer to draw power. | | Connects the chillpad to the computer to draw power. | ||
- | | | + | | [[Image:LaptopChillPad_USB.jpg|thumb|center|100px|USB Connector]] |
|- | |- | ||
| 15 | | 15 | ||
| Switch | | Switch | ||
| 1 | | 1 | ||
- | | | + | | 3.7 |
- | | Plastic | + | | Plastic |
- | | Molding | + | | Injection Molding, Assembled |
| Allows the user to control the fan speeds. | | Allows the user to control the fan speeds. | ||
| [[Image:LaptopChillPad_Switch.JPG|thumb|center|100px|Switch]] | | [[Image:LaptopChillPad_Switch.JPG|thumb|center|100px|Switch]] | ||
Line 299: | Line 412: | ||
| Wires | | Wires | ||
| 1 | | 1 | ||
- | | | + | | 4.2 |
- | | | + | | Copper |
- | | | + | | Purchased |
| Connects the motor to the switch and then to the USB Connector. | | Connects the motor to the switch and then to the USB Connector. | ||
- | | | + | | [[Image:LaptopChillPad_Wire.jpg|thumb|center|100px|Wire]] |
+ | |- | ||
+ | | 17 | ||
+ | | Logo Tab | ||
+ | | 1 | ||
+ | | 2.3 | ||
+ | | Rubber | ||
+ | | Injection Molding | ||
+ | | Marketing purpases | ||
+ | | [[Image:LaptopChillPad_LogoTab.jpg|thumb|center|50px|Logo Tab]] | ||
+ | |- | ||
+ | | 18 | ||
+ | | Small Screw | ||
+ | | 2 | ||
+ | | < .1 | ||
+ | | Steel | ||
+ | | Purchased | ||
+ | | Attaches the logo tab to the chill pad | ||
+ | | [[Image:LaptopChillPad_LogoScrew.jpg|thumb|center|50px|Small Screw]] | ||
|} | |} | ||
+ | <br> | ||
+ | ===Assembly=== | ||
+ | The numbers coordinate with the part number in the bill of materials.<br> | ||
+ | [[Image:LaptopChillPad_Big_picture_with_labels.jpg|thumb|center|600px|This is a labeled picture of all the parts]] | ||
+ | <br> | ||
+ | [[Image:LaptopChillPad_Zoom1_with_labels.jpg|thumb|center|600px|Zoomed in picture on some of the small parts]] | ||
+ | <br> | ||
+ | [[Image:LaptopChillPad_Zoom2_with_labels.jpg|thumb|center|600px|Zoomed in picture on some of the small parts]] | ||
==Team Member Roles== | ==Team Member Roles== | ||
+ | For coordinating the work, we had group meetings in which we all helped with high level brainstorming for all the parts of the analysis. After that, each group leader worked on on his respective area and would ask for the group help, if and when needed.<br><br> | ||
Phase I Team Roles | Phase I Team Roles | ||
* Team Leader - James Chon | * Team Leader - James Chon | ||
Line 313: | Line 453: | ||
* DFE Leader - David Gregor | * DFE Leader - David Gregor | ||
* FMEA Leader - Brenden Patch | * FMEA Leader - Brenden Patch | ||
+ | <br> | ||
+ | ==References== | ||
+ | |||
+ | 1. [http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries How to Prolong Lithium-based Batteries] | ||
+ | <br> | ||
+ | 2. [http://www2.sdge.com/tariff/com-elec/DR-LI.pdf Residential Customer Rate Information ] | ||
+ | <br> | ||
+ | 3. [http://www.eiolca.net/ ECONOMIC INPUT-OUTPUT LIFE CYCLE ASSESSMENT ] | ||
+ | <br> | ||
+ | 4. [http://support.dell.com/support/topics/global.aspx/support/kcs/document?&docid=405686#Issue1 Dell Laptop Battery FAQ ] | ||
+ | <br> | ||
+ | 5. [http://h18000.www1.hp.com/products/quickspecs/13401_na/13401_na.HTML HP Long Life Batteries ] |
Current revision
Contents |
Executive Summary
We have completed a preliminary design study of the Logitech Cooling Pad N200. Initially, group discussions included problems with the existing model as well as possible and feasible improvements. With these in mind, we conducted a product dissection study. Our analysis of the design consisted of four approaches: design for manufacturing, design for assembly, failure modes and effects, and design for environment.
After conducting the design analysis for manufacturing and assembly, we can conclude that for the most part, the product has been designed for efficient manufacturing and assembly. Few possible design improvements linger, but determining their actual effectiveness will require further study on product use and specific manufacturing and assembly methods.
Our design for environment analysis showed that the production of our product would result in a minuscule CO2 tax, less than 2% of the retail value. Nearly 90% of our greenhouse gas emissions came from the laptop manufacturing and electricity production. Our product saves the user from replacing their laptop battery once throughout the product's lifespan which would cause the CO2 tax to be lowered.
Failure modes and effects analysis showed that the product is not likely to experience severe, commonly occurring and difficult to detect modes of failure. The biggest concerns are with the USB cord, specifically a break in the inner wires. Introducing a retractable element to the pad design would leaving no slack in the cord, lowering the occurrence of this failure. In general though, most failures can be fixed with simple design changes, allowing us to focus more on environmental and cost considerations.
After conducting the design analysis, we concluded that
the product was designed to optimize manufacturing and assembly.
We decided that our design would be more focused on the product performance
than on the manufacturing and assembly aspect. Our improvements are going
to focus mostly on the usage phase. Improving product performance would have
a significant effect on the battery life.
Stakeholders Information
There are four stake holders for the chill pad: the customer, the retailer, the manufacturer, and the shipper.
Customer
The primary consumers for chill pads are users who intensively use their laptops such as gamers and most college students. College students are much more likely to have laptop computers and laptops typically overheat when the user is playing games. Because the chill pad would be used mostly in dormitory settings, portability is not a main priority. Rather, durability and effectiveness are more important for the target consumer.
Customer Needs:
- Relatively cheap- under $50
- Life span- 3-4 years
- Effective cooling
- Less noise than computer
- Multi-surface use
- Effective fan mobility/placement
- Portability (semi)
- Well designed
- Good ergonomics
- Easy powering option (usb or battery or plug in wall)
- Adjustable power settings
- Low weight
- Adaptability to laptop size
- Manageable Size
Retailer
The primary retailers are those who directly sell the product to consumers, varying from electronic stores to online retailers. They can be identified as stores that primarily sell technology-related products. These stores would prefer a slick design as well as product performance to attract younger, more tech savvy consumers.
Retailer Needs:
- Good presentation
- Outstanding performance
- Good yet cheap material
- Less custom parts
- Standardization
- Easy to replace parts
Manufacturer
Manufacturers are responsible for mass production of products. Therefore they would value low production costs.This means lower costs for raw materials, simple assembly, among others.
Manufacturer Needs:
- Low production cost
- Fewer parts
- Parts with simple molds
- Less materials
- Common materials
- Cheap materials
- Easy to work with materials
- Low assembly time
Shipper
Shipping/transport stakeholders are primarily commercial delivery companies. They would benefit from lighter, easily packaged products, and small manageable packages.
Shipper Needs:
- Durable product
- Small and durable packaging
- Low weight
User Study
Usage
Different chill pads have variations in their use. However the basic steps are as follows:
1. Place chill pad on surface
2. Place laptop on chill pad
3. Plug chill pad into laptop
The specific steps for the N200 Chill Pad were as follows:
These are the instructions for another chill pad that we tested.
Effects
An experiment was conducted that assessed the effects of the chill pad on the temperature of a laptop. The stages of the experiment are as follows:
1.Ran several programs on a computer(SolidWorks, a graphic-intensive game, and youtube video) with the chill pad on (apprx 12 mins)
2.Continued running same programs on computer with chill pad off (apprx 8 mins)
3.Continued running same programs on laptop with chill pad on (apprx 3 mins)
The temperatures of the internal components (core 1 and 2 of a dual core computer processor) were measured during these three phases, and the results are graphed below:
The laptop had many programs running simultaneously which in turn increased the temperature within the laptop. After reaching the steady state without the chill pad, the chill pad was then turned on. The chill pad had a significant role in cooling the laptop because after the chill pad was turned on, the temperature of the cores on the computer dropped 20 degrees.
This table shows the results of high temperature on batteries. As can be seen, subjecting the laptop to high temperatures significantly and permanently decreases the battery life. During high activity, laptop interiors can reach temperatures up to 180 degrees Fahrenheit.
Design For Manufacturing and Assembly
Design for Manufacturing
The competitor’s product has been designed well with respect to manufacturability, especially in high volumes. The product has a low complexity as well as a part count that matches its level of complexity. All of the plastic parts are injection molded and have been designed well with respect to their manufacturing process. For instance, each part has uniform wall thickness and has ribs and other strengthening features with good dimensions. In addition, the manufacturer made new parts for parts with different geometry in order to keep the molds simple. Another good feature is that the coloring of parts can be incorporated into the molding process, thereby cutting down on the steps needed to manufacture the product. Once the parts are molded, they do not need secondary operations, except for painting on the Logitech logo on the front of the chillpad.
Another well designed aspect is the use of rubber spacers in between the top and bottom cover. One of its main uses is that it allows for lower requirements on tolerance of the molds, thus making the molds cheaper.
The most number of parts comes from the number of screws. Although this could be lowered by changing from screws to a molded in, snap-fit feature, using screws allows the part to be assembled easier, allows for the ability to open the product without breaking it, and keeps the mold simpler and cheaper. However, instead of having different screws, the screws can be standardized for all uses.
In summary, the competitor’s product has been designed well for manufacturing and there is little room for improvement in this area.
Well-Designed
- Relatively low part number and simple parts
- Mostly all parts injection molded
- Plastic material, easy to work with
- allows color to be built in, instead of painting
- Parts designed well for molding: same wall thicknesses, ribs and strengthening features are good dimensions
- Areas of the part with different geometries were made into different parts,
- To keep mold simple
- Used rubber stoppers between parts to account for tolerances
- Lower tolerance allowed
Areas of Improvements
- Different screws, standardize them
Design for Assembly
Although the design for assembly can be improved on, most aspects of the design have been optimized to enable an easy, cheap assembly process. As for major improvements, the fan containment shell could be joined with the bottom body piece as one piece. There could be certain problems regarding the manufacturing process, but it would improve the design for assembly. In addition, the fan and shell casing components could be a subassembly that could be manufactured separately. The Logitech logo piece is unnecessary and just adds to the complexity of the assembly. Lastly, joining the felt to the bottom piece provides an assembly complexity as it may require multiple assembly directions or manual assembly. As for minor improvements, screws could be replaced with snap-fit designs and the screws necessary could be standardized. As for the current design, the elastic spacers between two parts are a useful inclusion for variable manufacturing tolerances. Another noteworthy design decision was the fan subassembly. The fan component contained a circular magnet, and it rested over a chip with four copper coils, a simple electrical motor with no rotating shafts or additional components to bog down the assembly and manufacturing processes. The general assembly process seems unambiguous and the assembly surfaces are kept to a decent minimum.
Well-Designed
- Assembly directionality is mostly unambiguous and simple
- Fan subassembly is designed to function without rotating shaft
- Elastic spacers are used to fit pieces with variable manufacturing tolerances
Areas of Improvement
- Fan and casing could be subassembly
- Rubber Logitech piece is unnecessary and just adds to manufacturing and assembly complexity
- Attaching felt onto plastic piece provides assembly complexity
FMEA (Failure Mode and Effects Analysis)
Table
Failure Modes and Effects Analysis - Laptop Chill Pad | |||||||||
---|---|---|---|---|---|---|---|---|---|
Items and Function | Failure Mode | Effects of Failure | Severity | Causes of Failure | Probability of Occurrence | Design Control | Detectability | RPN | Recommended Actions |
Fan - cools laptop | Fan blades break off | Laptop heats up | 6 | Dent/Other Defect Causes Fan to Collide with Casing | 1 | Tolerance Testing on Fan/Casing | 3 | 18 | Keep Injection Mold Simple to Avoid Defects |
Fan stops spinning | 7 | Fatigue, Loss of Power from Motor | 1 | Fatigue Testing of Fan | 1 | 7 | Choose Material to Meet Needs | ||
USB - Provides Power | Disconnection | Loss of power to chill pad | 2 | Loose Port, Something Snags Cord | 7 | None | 1 | 14 | Entertain options for compact cord wrapping |
Broken inner wires | Loss of functionality | 6 | Damage to cord | 2 | 3 | 36 | None (Out of Designer Control) | ||
Bend on connector | Connector could break off inside laptop | 7 | Bumping Connector While Inside Port | 2 | 1 | 14 | |||
Power diverted elsewhere | Lower performance of chill pad | 2 | Too Much Usage from Programs | 3 | 3 | 18 | Keep Software to Low Power Usage Specs | ||
Casing - Protects fan | Fan blades break off | Laptop heats up | 6 | Dent/Other Defect Causes Fan to Collide with Casing | 1 | Tolerance Testing on Fan/Casing | 3 | 18 | Keep Injection Mold Simple to Avoid Defects |
Motor - Drives Fan | Fatigue | Stops rotating fan | 6 | Electrical Problem, Demagnetization | 1 | Cyclic Testing of Motor | 3 | 18 | Entertain Different Motor Configurations |
Air Intake - Allows Air to Enter Through Bottom | Allowance of More than Air to Get Through Fan | Lower fan performance, Possible damage fan | 3 | Over-sized openings | 3 | Testing with Dust/Debris Under Chill Pad | 2 | 18 | Reduce Hole Size |
Mechanism Holding USB Cord Breaks | No convenient storage of for USB Cord | 3 | Broken(Yielded) Tabs | 3 | Cyclic testing of tabs | 2 | 18 | Retractable USB Cord | |
Grill - Allows Air Through Top | Particles slipping through grill | Possible damage to fan | 3 | Over-sized openings, Damaged grill | 2 | Strength testing of grill | 2 | 12 | Change Angle of Grill, or Use Different Cooling Method |
Screws - Holds Assembly Together | Loosening | Assembly falling apart | 4 | Overuse, Fatigue | 2 | Testing of regular use | 3 | 24 | None (Out of Designer Control) |
Rubber stoppers - Stops the computer from slipping | Disconnects from grill | Laptop slips off chill pad | 4 | Overuse, designed too loosely | 3 | Load and cyclic testing on stoppers | 2 | 24 | Put stronger grips on rubber stopper or adhere them differently |
Rubber spacers - Pushes apart the top and bottom cover | Rubber tears | Top and bottom are not tightly connected everywhere | 4 | Overuse, weak rubber material | 2 | Cyclic testing on the assembly with spacers | 4 | 32 | Add more support to lessen the load on each spacer |
Results
Across the board, the detectability scores for the device’s failure modes are very low, that is, anything that goes wrong with the device will be quickly and easily spotted by the user. The highest RPN value is associated with the mode of failure wherein the USB cord stops transmitting power due to damaged wires inside. This is a critical failure mode because it compromises the functionality of the whole device, the part is not easily replaceable, and USB wires are not typically very strong. To combat this potential failure, we propose a mechanism to retract the cord, which would avoid situations where slack in the cord makes it susceptible to damage. Another major concern from the analysis above is a tear in the rubber spacers between the top and bottom plates of the chill pad. More in depth analysis should be done to test whether the material of the rubber is strong enough to withstand overuse or if more support points should be added to better distribute the load. In general though, these failure modes have mostly low scores, and we do not expect them to get in the way of improving on the product’s design for cost effectiveness, lessening environmental impact, and other factors more constraining than failure mode analysis.
Design for Environment
As companies and engineers are becoming more aware of how their products impact the environment, consideration of this has been added to the product design process. As global warming becomes a more widely recognized fact, the reduction of greenhouses gas emissions has become important. With a possibility of a federal tax on the emissions of greenhouse gases($30/mt), it is necessary to conduct a study on how this tax would effect a laptop chill pad.
Production
Greenhouse Gases
Using the EIOLCA model (See reference #3 at the bottom) we were able to determine an estimate on the total amount of CO2 the production phase of a laptop chill pad would produce. We ran the model using the small electrical appliance manufacturing sector(#335210) with an input of $1 million. As seen on the chart on the left 570mt of CO2 were emitted. Scaling this to the emissions for the manufacturing of a single laptop chill pad costing $40 we found that 0.0228mt of CO2 are released. A $30/mt tax would cost a company an additional $0.68 per laptop which is 1.7% the total cost.
Economic Activity
An analysis of the economic activity shows that per $1 million spent on the retail value of the product, $2.18 million is spent in creating it.
Use
There are two components that are used in conjunction with our product. The first and most obvious is a laptop that the chill pad is specifically designed for. The second component is the electricity that is needed to power the laptop while it is in use.
Laptop
Greenhouse Gases
The CO2 emissions that are involved with the manufacturing of a laptop are needed. The EIOLCA model was used with an input of $1 million to determine the amount of CO2 emitted. For a laptop we choose to use the electronic computer manufacturing sector, #334111. A total of 284 mt of CO2 were produced and when scaled to the production of a single laptop(~$1000) we see that 0.28mt of CO2 are emitted. With a tax of $30/mt this equates to $8.52 or 0.852% the total cost.
Electricity Production
Greenhouse Gases
The production of the electricity needed to power the laptop emits C02. As done previously the EIOLCA model is used per $1 million to compute an estimation. The power generation and supply sector, #221100, was run to determine that 9370mt of CO2 were emitted per $1 million. A few assumptions were made to determine the impact for the chill pad's life cycle:
1. An average laptop uses 70 watts per hour
2. An average user will use their laptop for 2.5 hours a day
3. The chill pad has a life cycle of 3 years.
4. 1 kWh costs $0.112 (See Reference #2)
Using these parameters we estimate that 191.625 kWh are consumed at a cost of $21.46. Thus per life cycle 0.2010802mt of CO2 are emitted at a cost of $6.03.
Battery
We assumed that a laptop battery lasts 1.5-3 years(See References #4 & #5) and thus the consumer would replace the battery once throughout the chill pad's lifespan. Analyzing the emissions in producing a single laptop battery shows that 0.05mt are emitted. With the CO2 tax this would equate to $1.56. However our analysis in the User Study section illustrates the chill pad has the potential to cool the laptop enough to allow the battery to last the duration of the chill pad's lifespan.
Conclusion
The summary for the analysis of the environmental impact from production and usage phases are displayed in the table below. The pie graph shows the breakdown of how each component contributes to the overall CO2 tax that we would incur. The important takeaway is that the production phase only accounts for $% of the total CO2 tax. The laptop manufacturing and electricity production account for the majority of the tax, combining for 87%. While the manufacturing of a laptop battery is only a tenth of the overall tax, it has the possibility to be negated. Early evidence shows that the chill pad has the possibility to keep the laptop at a cool enough temperature that it will extend the battery's lifespan. If this longer lifespan can last the duration of the chill pad's lifespan then the consumer would not have to purchase a new battery and would lower our CO2 tax.
Bill of Materials
The chill pad consists of five simple components: top cover, bottom cover, air intake, grill, and fan subassembly. The assembly is fairly straight forward. There are 16 parts we identified in the assembly. It consists mostly of plastic parts which were manufactured using different molding methods. Several metal screws were used to attach the components together. There are electrical components in the assembly that we did not disassemble such as the motor, switch and the USB connector. In the table below, the parts we identified are listed along with their properties and functions.
List of Components
Part Number | Part Name | Quantity | Weight (g) | Material | Manufacturing Process | Function | Part Image |
---|---|---|---|---|---|---|---|
1 | Top Cover | 1 | 262.2 | Plastic | Injection Molding | Connects to the top grill and bottom cover. Protects inner workings. | |
2 | Top Grill | 1 | 170 | Plastic | Injection Molding | Connects to the top cover. Protects the fan and allows fan blown air to go through. | |
3 | Screws | 5 | < 1 | Steel | Purchased | Connects the top cover to the bottom cover. | |
4 | Rubber Screws | 4 | .25 | Rubber | Injection Molding | Connects the fan assembly to the top cover. | |
5 | Fan Casing | 1 | 16.5 | Plastic | Injection Molding | Connects to the top cover and the fan. | |
6 | Fan | 1 | 25 | Plastic | Injection Molding | Spins and blows air through the grill. | |
7 | Motor | 1 | 7.4 | Various | Purchased | Connects to the fan. Spins the fan. | |
8 | Felt | 1 | 40 | Felt | Purchased | Glued to the bottom cover. Provides soft interface between the user and product. | |
9 | Bottom Cover | 1 | 186 | Plastic | Injection Molding | Connects to the top cover and protects the inner workings. Provides a base for the product. | |
10 | Air Intake | 1 | 81 | Plastic | Injection Molding | Connects to the bottom cover. Allows air to flow into the chillpad. | |
11 | Small Screws | 3 | < .1 | Steel | Purchased | Connects the air intake to the top cover. | |
12 | Rubber Spacers | 4 | .25 each | Rubber | Injection Molding | Pushes on the top and bottom cover to provide a space in between. | |
13 | Removable Rubber Stoppers | 2 | 12 each | Rubber | Injection Molding | Connects to the top grill. Provides increased friction between the laptop and chillpad to keep it from moving. | |
14 | USB Connector | 1 | 4.3 | Various | Purchased | Connects the chillpad to the computer to draw power. | |
15 | Switch | 1 | 3.7 | Plastic | Injection Molding, Assembled | Allows the user to control the fan speeds. | |
16 | Wires | 1 | 4.2 | Copper | Purchased | Connects the motor to the switch and then to the USB Connector. | |
17 | Logo Tab | 1 | 2.3 | Rubber | Injection Molding | Marketing purpases | |
18 | Small Screw | 2 | < .1 | Steel | Purchased | Attaches the logo tab to the chill pad |
Assembly
The numbers coordinate with the part number in the bill of materials.
Team Member Roles
For coordinating the work, we had group meetings in which we all helped with high level brainstorming for all the parts of the analysis. After that, each group leader worked on on his respective area and would ask for the group help, if and when needed.
Phase I Team Roles
- Team Leader - James Chon
- DFMA(Assembly) Leader - Jay Kim
- DFMA(Manufacturing) Leader - Mukul Bhatt
- DFE Leader - David Gregor
- FMEA Leader - Brenden Patch
References
1. How to Prolong Lithium-based Batteries
2. Residential Customer Rate Information
3. ECONOMIC INPUT-OUTPUT LIFE CYCLE ASSESSMENT
4. Dell Laptop Battery FAQ
5. HP Long Life Batteries