Dynamics of Helical Gears
This model illustrates the dynamics of helical gears. It is built using the gears functionality in the Multibody Dynamics interface in COMSOL Multiphysics. A transient study is performed to analyze the effect of constant gear mesh stiffness, varying gear mesh stiffness, and the transmission error on the angular velocity of driven gear and the contact force. An eigenfrequency analysis is ...
Rolling of a Rigid Wheel
The purpose of this model is to demonstrate pure rolling of a rigid wheel when given an initial forward velocity together with a prescribed lean about this direction. It is assumed that the the rolling motion of the wheel is not affected by contact such that all three components of the velocity at the point of contact with the ground are zero. In order to achieve this, the velocity constraints ...
Modeling of Centrifugal Governor
A centrifugal governor is used to control the speed of rotating machinery. One of the most common applications is in controlling the RPM of an engine by regulating the fuel supply. This model illustrates the functioning of a spring loaded centrifugal governor. The dynamics of the governor are analyzed under the influence of a centrifugal force, spring force, and damping force. The sleeve ...
Lumped Model of a Vehicle Suspension System
In this example, a lumped model of a vehicle suspension system having 11 degrees of freedom is analyzed. The _Mass_, _Spring_, and _Damper_ nodes of the _Lumped Mechanical System_ interface are used to model the wheels, including suspension system as well as the seats with a passenger. The vehicle body, having 3 degrees of freedom, is modeled as a rigid body in the _Multibody Dynamics_ ...
Hinge Joint Assembly
This example illustrates how to model a barrel hinge connecting two solid objects in an assembly. In this model, the details of the connection are not the focus of the analysis, therefore, the hinge joint is modeled using a Joint feature in the Multibody Dynamics Module. The connected parts can be either rigid or flexible or a combination as shown in this model.
Differential Gear Mechanism
This model simulates the mechanism of a differential gear used in cars and other wheeled vehicles. A differential allows the outer drive wheel to rotate faster than the inner drive wheel during a turn. This is necessary when a vehicle turns in order to allow the wheel that is traveling along the outside of the turning curve to roll faster and to cover greater distance than the wheel on the ...
Simulation of a Counterweight Trebuchet
In this multibody dynamics model of a simple counterweight trebuchet, a parametric sweep is used to study throwing distance as function of the sling length. For more details on performing a multibody analysis of a counterweight trebuchet, see this blog post: [What Is the Physics Behind a Counterweight Trebuchet?](/blogs/what-is-the-physics-behind-a-counterweight-trebuchet/)
Truck Mounted Crane
Many trucks are equipped with cranes for load handling. Such cranes have a number of hydraulic cylinders, controlling the motion, and several mechanisms. The cylinders and mechanisms that make up the crane are subjected to large forces when handling heavy loads. In order to determine the load carrying capacity, these forces must be computed. This model uses the Multibody Dynamics Module, ...
Centrifugal Governor Simulator
Centrifugal governors, a specific type of governor, control the speed of an engine by regulating the amount of admitted fuel. In order to maintain a near-constant speed, regardless of the load or fuel supply conditions, centrifugal governors use the principle of proportional control. While the governor is in operation, it is critical that it quickly reaches a new steady-state configuration. ...
Mechanics of a Golf Swing
How well you can strike a golf ball is not only determined by your muscle strength, but more importantly it is influenced by the mechanics of golf swing. The outcome of golf stroke is basically determined by the movement of the club head just prior to the impact with the ball. In this example, a multibody analysis of a golf swing is performed. Aim of the analysis is to maximize the club head ...