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- Max rover weight: 50 kg
- Max object weight for Extreme Retrieval and Delivery mission: 5 kg
- Assuming we carry at max 2 rocks at a time
- Assuming we operate under 48 V
- Assuming the drivetrain will use 6 motors (each design we're considering is a 6wd and requires a motor per wheel)
- Assuming a wheel diameter of 9", or 0.229 m
- Ideally, with any variety of rocker-bogie design, the load is spread equally across the 6 wheels in any position
- Setting a safety factor of 2
- Assume a 10% efficiency loss per gearbox stage
Rough Calculations
1. Under our above assumptions, determine the weight acting upon a single wheel/motor
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| Motor Name | Price (USD) | Mass (g) | Max Voltage (V) | Body Length (mm) | Free Speed (RPM) | Stall Torque (Nm) | Stall Current (A) | Number of Pole-Pairs | Gearbox Suggestion | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ODrive Dual Shaft Motor 150 Kv | $109 | 890 | 48 | 2880 | 3.86 | 70 | 7 | |||||||
| Maxon EC 60 Flat | $147.84 (order of 1-4) $129.93 (order of 5-19) | 375 | 48 | 48 | 4020 | 4.87 | 43.2 | 7 |
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| Maxon EC Frameless 60 | On request | 333 | 48 | 37 | 3970 | 5.01 | 43.8 | 7 |
Requires a custom housing to pair with a 83:1 or greater gearhead Ex. 83126:1 Planetary Maxon Gearhead
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