5. Battery And DC Motor Sizing - L-division-2019-2020-Even/Repo-13 GitHub Wiki
Motor Sizing
Force= Weight * G
Torque = Force * Radius
Approximate weight of whole machine = 1500 Gram
Approximate weight on one DC motor = 375 Gram
Radius = 50 Mm
Force = 3.675 N
Torque = 0.18375 N-m = 1.8737285413468914 Kg-cm
Net torque= torque * Factor of saftey(1.5)= 2.8105928120203371 kg-cm = 3 Kg-cm (Aprox)
Therefore we require a motor with minimum of 30 rpm.
Battery Sizing
| Component | Current Drawn(mA) | Units used | Total Current(mA) |
|---|---|---|---|
| DC motor | 300 | 4 | 1200 |
| Pump | 350 | 1 | 350 |
| LED | 20m | 2 | 40 |
| Buzzer | 40 | 1 | 40 |
| 1630 |
Battery Requirement= current drawn * time = 1630 mA * 3hours = 4890 mAh
Battery size required is 9-12volts = 5 Ah