- #1
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Anyone know a good web site, or two, that will tell me about working out the instantaneous centre of rotation; for links only I imagine.
TIA.
TIA.
Instantaneous centres of rotation
- Thread starter Fermat
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In summary, The conversation is about finding information on calculating the instantaneous centre of rotation. The first suggestion given is to search on Google, which brings up a link to a website that explains the concept briefly. Another method is mentioned, involving finding the speed of a point B using the speed of point A and the angular speed, and calculating the position of the centre of velocity. Finally, the conversation mentions using Kennedy's theorem to find the instantaneous centres, which takes longer than the previous method of resolving velocities at the link ends.
- #2
radou
Homework Helper
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The first thing that came up on google [
]: http://www.fsid.cvut.cz/en/U2052/node27.html". Not much, depends on how deep you need to get into it.
By the way, if I recalled it correctly, if you know the speed [tex]\vec{v}_{A}[/tex] of a point A, and the angular speed [tex]\vec{\omega}[/tex], then you can find the speed of any point B with [tex]\vec{v}_{B}=\vec{v}_{A}+\vec{\omega}\times \vec{r}_{BA}[/tex], where [tex]\vec{r}_{BA}[/tex] is the vector from A to B. The condition on the centre of velocity is [tex]\vec{v}_{B} = \vec{v}_{c} = \vec{0}[/tex], so you can find its position.
]: http://www.fsid.cvut.cz/en/U2052/node27.html". Not much, depends on how deep you need to get into it.By the way, if I recalled it correctly, if you know the speed [tex]\vec{v}_{A}[/tex] of a point A, and the angular speed [tex]\vec{\omega}[/tex], then you can find the speed of any point B with [tex]\vec{v}_{B}=\vec{v}_{A}+\vec{\omega}\times \vec{r}_{BA}[/tex], where [tex]\vec{r}_{BA}[/tex] is the vector from A to B. The condition on the centre of velocity is [tex]\vec{v}_{B} = \vec{v}_{c} = \vec{0}[/tex], so you can find its position.
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- #3
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Many thanks.
I found a site (eventually - it took me ages, even on google) that told me what I was supposed to do. I used Kennedy's theorem to find the IC's and worked things out from there.
It was faster the first way I did it though. I just resolved velocities at the link ends and worked my way through the mechanism. Instantaneous centres gave the same answer, but took longer
I found a site (eventually - it took me ages, even on google) that told me what I was supposed to do. I used Kennedy's theorem to find the IC's and worked things out from there.
It was faster the first way I did it though. I just resolved velocities at the link ends and worked my way through the mechanism. Instantaneous centres gave the same answer, but took longer
FAQ: Instantaneous centres of rotation
What is meant by "instantaneous centres of rotation"?
"Instantaneous centres of rotation" refers to the point or axis around which an object appears to be rotating at a particular moment in time. It is a concept used in the study of kinematics and is often used to analyze the motion of complex systems.
How are instantaneous centres of rotation calculated?
The position of an instantaneous centre of rotation can be calculated using the principle of superposition, which involves considering the motion of different points on an object separately. By analyzing the velocities and accelerations of these points, the position of the instantaneous centre of rotation can be determined.
What is the significance of knowing the instantaneous centre of rotation?
Knowing the instantaneous centre of rotation allows for a better understanding of the motion of an object. It can help determine the direction and speed of motion, as well as the forces acting on the object. This information is useful in various fields such as engineering, robotics, and biomechanics.
Can an object have multiple instantaneous centres of rotation?
Yes, an object can have multiple instantaneous centres of rotation at different points in time. This is because an object's motion is constantly changing and thus, its instantaneous centre of rotation also changes. However, at any given moment, an object will only have one instantaneous centre of rotation.
How does the concept of instantaneous centres of rotation relate to rotational motion?
The concept of instantaneous centres of rotation is closely related to rotational motion. In rotational motion, an object is rotating around a fixed axis, which can be considered as the instantaneous centre of rotation. By analyzing the motion of an object's parts around this axis, we can determine the overall rotational motion of the object.