Motion analysis of Planetary Gear System
Objective:
- To create 3D parts of the Planetary Gear System.
- To assemble and simulate the motion anlaysis of Planetary Gear System under various scenarios.
- To obtain the angular velocity of the output.
- To plot and observe the results.
Introduction and Theory of Planetary Gear System:
An epicyclic gear train (also known as planetary gear) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates to carry one gear, called the planet gear or planet pinion, around the other, called the sun gear or sun wheel. The planet and sun gears mesh so that their pitch circles roll without slip. A point on the pitch circle of the planet gear traces an epicycloid curve. In this simplified case, the sun gear is fixed and the planetary gear(s) roll around the sun gear.
An epicyclic gear train can be assembled so the planet gear rolls on the inside of the pitch circle of a fixed, outer gear ring, or ring gear, sometimes called an annular gear. In this case, the curve traced by a point on the pitch circle of the planet is a hypocycloid.
3D modelling of parts:
Inputs
- Ring Gear
- Module = 2.5 (You must use the metric system in design modeler)
- Number of teeth = 46
- Sun Gear
- Number of teeth = 14
- Input Speed of the Gear = 200 rpm.
- Number of planet gears = 4
From the inputs of Ring gear and Sun gear, the pitch circle diameter or number of teeth can be calculated. So after calculatiing, it can out be 16 teeth for planet gears.
Modelled parts and Assembly
Sun gear
Ring gear
Planet gear
carrier
Assembly
With the above input parameters, you are going to run a simulation on the following cases,
| Sl.No | Input | Output | Fixed |
| 1 | Sun Gear | Carrier | Ring Gear |
| 2 | Ring Gear | Carrier | Sun Gear |
| 3 | Sun Gear | Ring Gear | Carrier |
PLOTS AND RESULTS:
Scenario 1
Input : Sun gear
Output : Carrier
Fixed : Ring gear
For the Motion Analysis study, the following conditions to be applied
* Rotating motor is applied to the Sun gear with 200 rpm and direction of rotation.
* All contacts are defined between the driver and driven wheels
* Simulation is then run for the required time length and results are saved.
Angular Velocity of the output:
Scenario 2
Input : Ring gear
Output : Carrier
Fixed : Sun gear
For the Motion Analysis study, the following conditions to be applied
* Rotating motor is applied to the Ring gear with 200 rpm and direction of rotation.
* All contacts are defined between the driver and driven wheels
* Simulation is then run for the required time length and results are saved.
Angular Velocity of the output:
Scenario 3
Input : Sun gear
Output : Ring gear
Fixed : Carrier
For the Motion Analysis study, the following conditions to be applied
* Rotating motor is applied to the Sun gear with 200 rpm and direction of rotation.
* All contacts are defined between the driver and driven wheels
* Simulation is then run for the required time length and results are saved.
Angular Velocity of the output:
Observations:
1. The angular velocity is three cases starts from zero and attains a certain value after some time, this is because of moment of inertia acting at the start of the motion.
2. The magnitude of angular velocity in each case is different to each other as the input and fixed parts changes but the profle of angular velocity is same for every case.