What is Rigid body dynamics: Definition and 68 Discussions
In the physical science of dynamics, rigid-body dynamics studies the movement of systems of interconnected bodies under the action of external forces. The assumption that the bodies are rigid (i.e. they do not deform under the action of applied forces) simplifies analysis, by reducing the parameters that describe the configuration of the system to the translation and rotation of reference frames attached to each body. This excludes bodies that display fluid, highly elastic, and plastic behavior.
The dynamics of a rigid body system is described by the laws of kinematics and by the application of Newton's second law (kinetics) or their derivative form, Lagrangian mechanics. The solution of these equations of motion provides a description of the position, the motion and the acceleration of the individual components of the system, and overall the system itself, as a function of time. The formulation and solution of rigid body dynamics is an important tool in the computer simulation of mechanical systems.
A perfectly rough rod is gently placed with one end
upon another rod of equal mass and in the same vertical
plane, moving with the velocity √2gc on a smooth table. If
the initial inclination of the first rod to the horizon be α, and
its length 2a, shew that it will just rise to a vertical...
Homework Statement
See attachment "problem"
Homework Equations
The Attempt at a Solution
See attachment "work" and "answer"
I got 0.92, but the book gives 1.73. Something went wrong, but I can't find it.
Let's say there are two rigid bodies in space, each has an initial translational velocity as well as an initial angular velocity. Eventually, these two bodies collide. The collision causes the translational and angular velocities of both bodies to change, resulting in 4 unknowns (each unknown...
Hi there!
It is the first I post here! Amazing Blog!
Well, I am studying Aerospace Engineering. Third Year. However this semestre I intend to repeat the course on Rigid Body Dynamics ( second year) , as I think it is very, very important to fully understand these topics.
So, I am...
Homework Statement
I want to analyse two colliding balls, rolling flat on a billiard table.
I have recorded two collisions from above the table. A 1D collision and a 2D collision.
In both collisions only 1 of the balls are rolling before the collision.
Known is:
mass of the balls: m1=207g...
Hello,
I am trying for a couple of hours now to integrate these equations ( http://en.wikipedia.org/wiki/Euler%27s_equations_%28rigid_body_dynamics%29 ) with the Euler's method: \dot{f}=\partial{f}/\partial{t}\cong\Deltaf/\Deltat=(f(t+\Deltat)-f(t))/\Deltat .
I am trying to do this...
Homework Statement
A pendulum consists of a light rigid rod of length 250mm, with two identical uniform solid spheres of radius 50mm attached one on either side of its lower end. Find the period of small oscillations (a) perpendicular to the line of centers, and (b) along it.Homework Equations...
Need help! Rigid Body Dynamics
Homework Statement
I'm having problem with the following problem. The encircled portion of the figure is giving me trouble. I am getting confused on how to correlate it with reference frame oxyz. please help. It's urgent.. :(
what is the significance of...
Homework Statement
The rigid body assembly is made from a 15 Kg disk, an 8 Kg slender rod, and a small 4 Kg sphere. The radius of the disk is R = 0.4 m and the length of the rod is L = 1.2 m. The pivot O is at the center of the disk. The assembly is released from rest at the horizontal...
Not really sure if this is where this should be but oh well.
1. Homework Statement
It is given that:
b = 200 mm
mass = 6 kg
Find the tension in cable A immediately after cord B is cut.
2. Homework Equations
Moment = I*alpha + m*a*d
F = ma?
3. The Attempt at a...
Homework Statement
A uniform rectangular tile drops without spinning until its corners reach positions
(0; 0; 0); (2a; 0; 0); (2a; 2b; 0); (0; 2b; 0), when it strikes the top of a vertical pole at a
point very close to the (0; 0; 0) corner. Just before impact the velocity of the tile was...
I'm currently programming a 2D rigid body dynamics engine.
While I have realistic collision detection and response between polygons, I have trouble in the simulation once I implement gravity.
When these rigid bodies are influenced by gravity, they never fall to complete rest (e.g. they...
Hi!
I have been working on a rigid body subject quite a long. But till now there is an unresolved question for me. When we calculating the torque acting on the rigid body we use the following definition of the torque: t = r X f, X - is a cross product. So if I calculate the torque in a...
Homework Statement
A 3.0 m long rigid beam with a mass of 130 kg is supported at each end. A 65 kg student stands 2.0 m from support 1. How much upward force does each support exert on the beam?
http://i241.photobucket.com/albums/ff4/alg5045/p13-56.gif
Homework Equations
The...
Hi,
I'm developing a video game, in which I'm making a charactar with rigid-body physics (sometimes called "ragdoll" physics). The way I've made it is probably not completely realistic, because I only use velocity vectors to calculate the position of each joint of the "ragdoll", based on an...
I've been presented with the following problems, and would like some help/affirmation:
SITUATION:
A billiard ball with mass m and radius r is in rest on a horizontal table. The ball is hit with a billiard cue the height r/3 above the table, and has the velocity v0 immediately after the hit...
Hello again! About my last problem (cone principal moments of inertia around top vertice), I´ve found the main moments of inertia, but I did so by integrating the moments of inertia dI o a disk rotaing about it´s diameter (1/4 ML^2, by table), and found the correct answer. But I have done this...
How different/similar is molecular dynamics from rigid body dynamics? Could I use RBD software such as ODE to simulate MD? What assumptions/modifications would I need to make for this to work (e.g. treat atoms as rigid spheres connected through some special type of joints)?