Good day to everybody,
I design a parallelogram type four bar mechanism that will lift a heavy load vertically.
The fixed joints of the four bar is on the half way between the first and the second position vertically. So an unstable condition would be unavoidable if the mechanism is driven from one of the cranks.
Should I use a linear actuator, if so what type can you suggest?
Or if you say a rotary one, since the cranks can not be used as the input, what type of extra linkage should I use? (In that case my four bar will be a six bar)
Thank you to so much beforehand...
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