5.E Motor sizing and Battery sizing of the system. - M-Division-2020-2021-Even/Repo_07 GitHub Wiki
5.E Motor Sizing & Battery Sizing.
5.E 1. Motor Sizing :
1.DC Motor :
- Mass of body to hold (m) = 0.125 + 0.175 = 0.3 Kg
- Diameter(D) = 0.08 m
- Acceleration due to gravity(g) = 9.8 m/s^2
- μ = 0.45
- F = m * g
- F = 0.3 * 9.8
- F = 2.94 N
Now considering friction
- F = mg * μ
- F = 2.94 * 0.45
- F = 1.323 N
- Now Torque : T = F * (D/2)
- T = 1.323 * (0.08/2)
- T = 0.05292 Kg-m
- T = 0.05292 * (100/9.8)
- T = 0.54 Kg-cm
- Considering Factor Of safety i.e FOS = 1.5
- Final Torque = T * FOS
- Final Torque = 0.54 * 1.5
- ∴ Final Torque = 0.81 Kg-cm @ 12V
- ∴ By comparing with table of specification for 0.81 Kg-cm Rated Torque. We have ,0.8 Kg-cm Rated Torque at 12V of 150 RPM ,therefore we need DC Motor Of 150 RPM @ 12V .
2. Servo Motor
- Mass of body to hold (m) =0.028 + 0.005 = 0.285 ≈ 0.3 Kg(Approx)
- Diameter(D) = 0.03 m
- Acceleration due to gravity(g) = 9.8 m/s^2
- μ = 0.4
- F = m * g
- F = 0.3 * 9.8
- F = 2.94 N
Now considering friction
- F = mg * μ
- F = 2.94 * 0.4
- F = 1.176 N
- Now Torque : T = F * (D/2)
- T = 1.176 * (0.03/2)
- T = 0.01764 Kg-m
- T = 0.01764 * (100/9.8)
- T = 0.18 Kg-cm
- Considering Factor Of safety i.e FOS = 1.5
- Final Torque = T * FOS
- Final Torque = 0.18 * 1.5
- ∴ Final Torque = 0.27 Kg-cm
- ∴ By comparing with table of specification for 0.18 Kg-cm Stall Torque,We need Servo Motor Of Specification Tower Pro SG-90.
- Operating Voltage : (3.0– 7.2 )V.
- Stall current : 650 mA.
∴ No. Of DC Geared Motors Required : 2.
& No. Of SG 90 Servo Motors Required : 2.
3. Battery Sizing :
| Sl No. | Components | Quantity | Voltage Required | Current Drawn |
|---|---|---|---|---|
| 1. | DC Geared Motor | 2 | 12 V | 600 mA |
| 2. | SG 90 Servo Motor | 2 | 5 V | 1400 mA |
| 3. | Ultra Sonic Sensor | 1 | 5 V | 40 mA |
| 4. | Arduino Mega 2560 | 1 | 5 V | 100 mA |
| 5. | Double Channel Relay | 1 | 5 V | 80 mA |
- So, for 12 V
- Current Drawn(C1) = 600 mA
- So, for 5 V
- Current Drawn(C2) = 1400+40+100+80 = 1620 mA
-
Now Considering Factor Of Safety i.e FOS = 1.2
-
C1 = 600 * 1.2
-
C1 = 720 mA = 0.720 A
-
C2 = 1620 * 1.2
-
C2 = 1944 mA = 1.944 A
- For Time(T) = 3 Hrs
- For 12 V
- Battery Required : 0.720 * 3 = 2.16 Ah.
- For 5 V
- Battery Required : 1.944 * 3 = 5.832 Ah.