Group 17 - For Kawasaki® KFX® Power Wheels: Gate 4
Critical Project Review
The group has worked very well throughout this entire project. The biggest challenge we faced was the loss of our group leader in the initial stages of the project, but this challenge was met by raising each individual’s expectations. While some gates were harder to accomplish (with an increasing workload for each member), everyone was able to piece the various parts of each gate together before it was due. Group members Parth and Dhruv have been responsible for the physical disassembly and reassembly of the product, and have been in charge of uploading the respective gate information to the Wiki. They took care of the more hands-on aspect of the project, since they had some knowledge of the Wiki format, 3D modeling experience, and mechanical experience. Isaac and Sam have been responsible for the technical aspects of the project, including the Project Management write ups and component documentation. Isaac and Sam have also been proofreading and making changes to the Wiki to make sure all of the necessary questions are answered in an understandable format.
To improve the report quality, we have made a much stronger effort to complete all aspects of the gate a few days before the deadline. This will allow us to go back into the Wiki and make sure we have enough time to upload or add missing information. Finishing the gate earlier also gives us the option to utilize office hours or email the TA’s with a reasonable amount of time for a response if we have questions.
We will have at least one more meeting before the final gate is due, to go over our presentation format and technical report. This meeting will take place either Tuesday or Wednesday of the week of November 13th, depending on everyone’s final exam schedule.
This section will contain the details of the product re-assembly.
Product Re-assembly Overview
The reassembly of the product took approximately two and a half hours to complete. The first ten minutes were spent deciding how to approach the reassembly, even with the dis-assembly procedure. The reassembly procedure is essentially the reverse of the dis-assembly procedure, but we needed to make sure everything would work in reverse. Overall, both the dis-assembly and reassembly were relatively simple. We initially believed the reassembly would be much more complex, but it was very easy. The first step we evidently decided to take was to put together the chassis, or the upper body component. The chassis includes the motor and gearbox, which were fitted back into their original respective positions. The body component was then fastened back together, and the handlebar component coupled with the tires was assembled last. The main frame of the bike was easier to connect back together than the more complex component system of the handlebars and steering axle.
Product Re-assembly Difficulty
We divided the difficulty level into three categories mentioned below:
If the difficulty level is easy, this means it did not take a lot of effort to determine how the components in that step went back together. A difficulty level of easy also means no complex tools were needed. A moderate difficulty level means the step required a little more physical labor, or it was not as straightforward to understand the component interactions. A hard difficulty level means the step took a lot of time to reassemble, the most physical labor, and that it required the most thought.
Product Re-assembly Detailed Table
During the re-assembly process there weren't many challenges we faced because it was very easy to re-assemble than it was to dis-assemble. The only part where we felt some difficulty was to assemble the complete chassis along with to assemble the gearbox with the motor in it and the rear wheels. Because it was so difficult to hold the chassis with the gearbox in it and enter the rear axle between the tooth locks of the gearbox. The rest of the re-assembly process was very easy without any difficulties.
Below Table has the detailed step-by-step description of the assembly process along with the difficulty level and time it took us to assemble the part. It should be noted that the 'approximate time required' is how look it took to actually physically attach or reassemble the components during that step. The total time spent in the lab was over two hours, because additional time was required to actually determine how we were going to reattach each piece. The physical reassembly of the product took very little time.
|Product reassembly procedure|
|Step No.||Procedure||Tool Required||Approximate Time Required(Min)||Difficulty Level||Image|
|1||Place the motor fixed with the gear box into the back part of the chassis. Connect all of the wires to their respective places, along with the PC Board.||Done by hand||1||1|
|2||Enter the rear axle through the tooth locks of the gearbox and then join the chassis with screws (using the screwdriver).||P1 Philips Head screwdriver||1:20||2|
|3||Put the main red colored body on the chassis, and fasten a screw in all the places where there are holes.||P1 Philips Head screwdriver||2||2|
|4||Attach the rear wheels with a socket wrench.||9/16" Socket Wrench||0:40||1|
|5||Attach the front axle and handle bars.||Done by hand||0:45||3|
|6||Attach the front wheels with a socket wrench.||9/16" Socket Wrench||0:40||2|
|7||Assemble the front Grill and the body support.||Done by hand||0:30||1|
|8||Assemble the seat and both the left and the right foot rest.||P1 Phillips Screw Driver||2:00||2|
The original dis-assembly of the product was completely different from the re-assembly. There was a sequence in the dis-assembly from top to bottom. That is we started dis-assembling from top to bottom whereas the re-assembly was completely different. We started from the base part which was the chassis and then moved on the body then finishing it with the wheels.
Methods and Tools
The same methods and tools were used in the original assembly
The only differences are that the original assembly was done by power wheel experts that had done it many times before.
One: Adding the Heat Sink
If the Kawasaki KFX power wheel were to overheat it could damage the plastic, the motor, and the battery, which would cause the power wheels life span to decrease. The Kawasaki would over heat if the power wheel had been running for a long period of time. When the power wheel is running it creates heat, which overtime will build up in the motor. Placing a heat sink next to the electric motor would absorb some of the heat so it would overheat and cause damage to the surrounding systems. The heat sink would keep the power wheel running longer. The heat sink would be small enough where dramatic changes to the bike would not be needed. The heat sink would be placed next to the motor which is in the rear of the bike, so room for the heat sink could be made under the back of the bike. Adding a heat sink would affect the four factors.
Economic- The addition of a heat sink could up the cost of production, which in return would raise the retail cost. However in the long run the bike will last longer, and not need repairs for over-heating.
Environmental- The addition of a heat sink would not have a large impact on the environment. The heat sink is made out of aluminum. Aluminum has a negative on the environment, in both production and waste.
Global- The heat sink would not affect global factors. The power wheel is made in areas where aluminum is available. There would be no preferences for styling because the heat sink would not be visible.
Societal- The addition of the heat sink would keep the power wheel from over-heating, over heating could melt the plastics, and even the battery. By doing so the power wheel is now safer for children to use.
Two: Adding Power outlet to charge the battery on the main body:
One of the main design revision we would like to make on our Product is to have a fixed battery and a charging wire, which could be directly plugged in a socket. The bike would start charging, and using a LiON battery would be a cheaper option and it would last longer than the normal battery.
Global- LiOn batteries are made in china and are made of cheap quality, yet they can explode due to over heating.
Economic Effect- using a LiON battery would be a Cheaper option as LiON is a cheaper brand. Using a portable battery generally more expensive than a fixed battery.
Environmental- Using a fixed battery will be a good option for environment as well, because the user cannot just dispose the battery anywhere. Only a fisher price agent will be able to take the battery out and dispose it in a safe place.
Three: Rubber Coating on Tires:
A change that we think would be really useful for making the bike better in performance as well as safety is having a rubber coating on outer shell of the tires. This would prevent the product from skidding and it would make it easier for the driver to handle the bike on slippery surfaces like snow.
Global effect- there will not be a large global impact if rubber coating is used because rubber can be easily produced worldwide.
Economic Effect- Using a rubber Coating will increase the cost to some extent, but wont be significant because rubber is cheap. If we only need to coat the tires instead of making the entire tire rubber, this will not be a huge economic impact.
"Kawasaki® KFX." Fisher-price.com <http://www.fisher-price.com/us/powerwheels/product.aspx?pid=47340>
"Power Wheels Parts Diagrams." mendingshed.com 13 OCT 2010 <http://powerwheels.mendingshed.com/P5066.pdf>