Talk:RC rock crawler truck
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| + | =Client Comments on Report= | ||
| + | We received your [http://ddl.me.cmu.edu/ddwiki/index.php?title=RC_rock_crawler_truck&oldid=16739 report]. The two DFMA suggestions of improving insertion of the motor and reducing unnecessary parts sound interesting. Your failure modes of axle failure, suspension deformation, and gear slippage make sense. You mention that the gear ratio is designed for torque rather than speed, but isn't it the combination of motor and geartrain that matters? It seems that the geartrain alone doesn't say much. | ||
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| + | Detailed comments: | ||
| + | * Nice list of customer needs, but it seems you are missing some important ones like performance, range, safety, noise, etc. | ||
| + | * Please explain user interaction with the product in greater detail. Also, please expand on the mechanism functions - how is speed regulated? How does the differential function? How does the suspension function? | ||
| + | * Your summary that some components are consolidated while others are not is interesting - can you be more specific? | ||
| + | * Great summary of DFMA - it looks like many of the guidelines were followed, and the assembly issue is interesting. | ||
| + | * Great FMEA findings. What scale are you using? | ||
| + | * How did you determine that the battery charging is 30W? Your use assumptions seem like very heavy use - please comment. You appear to have assumed a carbon tax of $200/ton. This seems unlikely - why did you assume this? In any case, it looks like the GHGs could be a significant cost even at a lower tax rate. Thank you for the clarity on how representative the EIO sector is. | ||
| + | * You mention that the gear ratios give you above average torque and below average speed. What is average, and where are you getting those numbers? Is the motor itself standard across all cars? If not, shouldn't the motor and gear ratio be examined together before being able to make such conclusions? Your final results of a 9:1 torque ratio seem reasonable, but what does it tell us? | ||
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| + | We look forward to seeing your market analysis and new ideas in the next report. | ||
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==Client comments on the Mechanical Analysis== | ==Client comments on the Mechanical Analysis== | ||
Revision as of 19:47, 2 October 2008
Client Comments on Report
We received your report. The two DFMA suggestions of improving insertion of the motor and reducing unnecessary parts sound interesting. Your failure modes of axle failure, suspension deformation, and gear slippage make sense. You mention that the gear ratio is designed for torque rather than speed, but isn't it the combination of motor and geartrain that matters? It seems that the geartrain alone doesn't say much.
Detailed comments:
- Nice list of customer needs, but it seems you are missing some important ones like performance, range, safety, noise, etc.
- Please explain user interaction with the product in greater detail. Also, please expand on the mechanism functions - how is speed regulated? How does the differential function? How does the suspension function?
- Your summary that some components are consolidated while others are not is interesting - can you be more specific?
- Great summary of DFMA - it looks like many of the guidelines were followed, and the assembly issue is interesting.
- Great FMEA findings. What scale are you using?
- How did you determine that the battery charging is 30W? Your use assumptions seem like very heavy use - please comment. You appear to have assumed a carbon tax of $200/ton. This seems unlikely - why did you assume this? In any case, it looks like the GHGs could be a significant cost even at a lower tax rate. Thank you for the clarity on how representative the EIO sector is.
- You mention that the gear ratios give you above average torque and below average speed. What is average, and where are you getting those numbers? Is the motor itself standard across all cars? If not, shouldn't the motor and gear ratio be examined together before being able to make such conclusions? Your final results of a 9:1 torque ratio seem reasonable, but what does it tell us?
We look forward to seeing your market analysis and new ideas in the next report.
Client comments on the Mechanical Analysis
This mechanical analysis mainly focuses on the gearbox design of the RC truck. My comments are in follows:
- Please state your assumptions for the mechanical analysis.
- As a client, I would like to an analysis with more depth or more applicative. For example, you can predict the steepest slope that this RC truck can climb (maximum gradability). The value can be simply calculated by using the output torque to wheel, wheel radius, vehicle weight and an assumed friction coefficient between the wheels and the ground.
