The Missing Umbrella
EGR314 Team 205 - Deepit Arora, Enoch Choi, Michael Gross
Project maintained by EGR314-Team205 Hosted on GitHub Pages — Theme by mattgraham
Appendix E - Component Selection
Component Research
Motor
| Option | Solution | Pros | Cons |
|---|---|---|---|
| 1 | Pololu HP Micro Metal Gear Motors Manufacturer #4794 $19.95 Product Link |
High torque Small size Low power consumption |
Low RPM Open gearbox |
| 2 | Johnson Motor PC280LG-303 $6.99 Product Link |
Low power consumption Higher RPM | Low torque |
| 3 | # Aslong motor ASJGY-370-6-150 $18.00 Product Link |
High torque Strong build |
Higher power consumption |
Choice: Pololu HP Micro Metal Gear Motors #4794
Rationale: We decided to go with this particular product since we are able to get relatively higher torque in a small form factor with low power consumption. This fits our product idea well.
Temperature Sensor
| Option | Solution | Pros | Cons |
|---|---|---|---|
| 1 | Analog Devices Inc. TMP36GT9Z $2.40 Product Link |
Can measure from -40 degrees to 125 degrees (Celsius) Requires 2.7-5.5V to power Inexpensive Analog |
Requires ADC Would need to configure specific resistances in the temperatures desired because of the large range the sensor can detect |
| 2 | Vishay Dale 02C5000FF $7.47 Product Link |
Smaller in size than above Can measure from -40 degrees to 125 degrees (Celsius) |
More Expensive Operating Voltage not specified |
| 3 | Microchip Technology TC74A4-3.3VCTTR $0.97 Product Link |
Previous In-Class experience with chip It is a surface mount component Can measure from -40 degrees to 125 degrees (Celsius) |
Only 7b resolution Less accurate for measurements less than 0 Component size is smaller compared to the other options |
Choice: Option 3: TC74A4-3.3VCTTR Temperature Sensor
Rationale: While the other options have a wider range of temperatures measure, this option was the best choice because it is the only option that is surface mount. Another reason is that we are familiar with this sensor from In-class assignments.
Hall Effect Sensor (Wind Speed Subsystem)
| Option | Solution | Pros | Cons |
|---|---|---|---|
| 1 | Adafruit 1733 $44.95 Product Link |
All in one solution Simple linear Voltage to Wind Speed conversion in datasheet |
Requires 7-24V to power Expensive Sensor Requires ADC Requires OpAmp |
| 2 | ams OSRAM AS5600-ASOM $3.46 Product Link |
I2C protocol Smaller physical footprint Wind cups can be 3d modeled or ordered |
Would require additional wind cup and structure Lower resolution Requires timer and equation implementation within code Requires external magnet |
| 3 | Bourns Inc. PEC12R-4025F-N0024 $1.25 Product Link |
Low cost solution for reading wind speed Wind cups can be 3d modeled as well | Would require additional wind cup and structure Lower resolution Requires timer and equation implementation within code Requires ADC |
Choice: AS5600-ASOM + External cup assembly (bought or designed)
Rationale: This hall effect sensor will simplify the electrically design while only slightly increasing the programming difficulty. Despite needing to calculate linear velocity from rotational position, this sensor will greatly reduce materials cost in both pcb footprint and external construct.
Power Supply
| Option | Solution | Pros | Cons |
|---|---|---|---|
| 1 | MicroChip MIC4575WU $4.58 Product Link |
Output is within desired range (1.2 - 37V) Familiarity Used previously in class |
Larger in size compared to other options Not always in stock Not surface mount |
| 2 | ROHM Semiconductor BD900N1G-CTR $1.34 Product Link |
Surface mount Reasonable output voltage (1.25 - 13.8V) | More expensive than above |
| 3 | Microchip Technology / Atmel LR12K4-G $1.97 Product Link |
High output voltage (1-88V) In stock | Most expensive of the three Smallest option |
Choice: MIC4575WU
Rationale: We chose the MIC4575WU switching voltage regulator because the team had familiarity with a variation of the chip from a previous semester’s project. Additionally, it it allows our team to tune the output to 3.3V at fairly cheap cost. Furthermore, the adjustable circuit is outlined in the datasheet with exact part numbers to generate the desired voltage output.
Power Control Module : Switching Voltage Regulator
| Option | Solution | Pros | Cons |
|---|---|---|---|
| 1 | Adam Tech PA-012 $9.71 Product Link |
Wall mount No load power consumption |
5V output may be too low for components |
| 2 | Adafruit Industries 1528-1835-ND $24.50 Product Link |
Not wall bound Can be recharged after use |
Most expensive option 3.7V may be too low |
| 3 | TKDY 9V 1.5A Power Supply Charger $12.99 Product Link |
Continuous short circuit protection Multiple adapters | No datasheet |
Choice: Adafruit Battery Pack
Rationale: The Adafruit battery is not bound to a wall outlet so it can be taken almost anywhere. It can also be recharged after every use and has a life cycle of at least 500 uses.