is this four bar linkage possible?
is this four bar linkage possible?
(OP)
hello!
I am want to design a four bar mechanism but I don't know if it is possible.
A motor moves the Input bar with the objective of making the output bar rotate 160º. Initially i wanted to make the output bar rotate 180 degress but i realized that it is impossible to do it without going through a blocking position (obviously), i think this position is call dead centre position in english ("posicion de bloqueo" in spanish)
The main idea is to begin in a position of maximum mechanical advantage (where the input link and the coupler link are aligned) and then activate the motor in order to move the output link 160 degrees. The mechanism has to be able to return to its initial position by chaing the direction of the motor rotation.
therefore, the conditions are the following:
- the mechanism should not pass through dead centre positions
- in the initial position, the mechanism has to be in (or close to) the maximum mechanical advantage position (input and coupler links aligned)
- the output bar has to rotate 160 degrees.
Is that even possible?
I've studied the different possibilites and I think that the only way of making this is with the Grashof "Crank-Rocker" mechanism where the crank is the input link. this way the motor rotates in one direction and there are no dead centre positions. but in this case i think it is impossible to make the rocker rotate 160 º....
thank you very much.
sorry for my english. If you don't understand something, pless ask. thanks again
I am want to design a four bar mechanism but I don't know if it is possible.
A motor moves the Input bar with the objective of making the output bar rotate 160º. Initially i wanted to make the output bar rotate 180 degress but i realized that it is impossible to do it without going through a blocking position (obviously), i think this position is call dead centre position in english ("posicion de bloqueo" in spanish)
The main idea is to begin in a position of maximum mechanical advantage (where the input link and the coupler link are aligned) and then activate the motor in order to move the output link 160 degrees. The mechanism has to be able to return to its initial position by chaing the direction of the motor rotation.
therefore, the conditions are the following:
- the mechanism should not pass through dead centre positions
- in the initial position, the mechanism has to be in (or close to) the maximum mechanical advantage position (input and coupler links aligned)
- the output bar has to rotate 160 degrees.
Is that even possible?
I've studied the different possibilites and I think that the only way of making this is with the Grashof "Crank-Rocker" mechanism where the crank is the input link. this way the motor rotates in one direction and there are no dead centre positions. but in this case i think it is impossible to make the rocker rotate 160 º....
thank you very much.
sorry for my english. If you don't understand something, pless ask. thanks again





RE: is this four bar linkage possible?
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: is this four bar linkage possible?
Try it - it is fun!!
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
Speaking of CAD, if you have access to any sort of system which supports parametric 'sketching' (in this case, a sort of modern version of 'cardboard & thumbtacks'), this sort of thing can be solved pretty easily.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
UG/NX Museum: http://www.plmworld.org/p/cm/ld/fid=209
To an Engineer, the glass is twice as big as it needs to be.
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
These things have become surprisingly inexpensive these days.
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
the paralelogram begins with the four links aligned, this is not a "maximum mecanical advantage" position. it is a singularity position.
RE: is this four bar linkage possible?
- Steve
RE: is this four bar linkage possible?
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: is this four bar linkage possible?
Why don't you tell us what you really need and maybe some of us could help you with a mechanism,but it WON'T be a 4 bar with your high MA demand.
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
Can't seem to open yor .avi file.
RE: is this four bar linkage possible?
Good solution
RE: is this four bar linkage possible?
Nice illustration motiongirl
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: is this four bar linkage possible?
RE: is this four bar linkage possible?
Only the OP has to decide. That's when your "black box" must be opened for inspection.