Height adjustment mechanism for slider crank mechanism

[Deepanjali]

In the current project, I need to convert rotational motion into linear motion using a crank and slider mechanism. The project requires the linear movement to range from 7 cm to 15 cm. Additionally, the system should allow for manual adjustment of the height, so the linear motion can oscillate from 0 cm to 8 cm, 0 cm to 9 cm, and so on, as needed. Can you suggest the appropriate mechanism to achieve this adjustable motion?

Mentor note: Thread moved to homework forum from technical forum, so no template.

 

[Baluncore]

Welcome to PF.

A rotating crank, with a connecting rod, rocks a slotted link back and forth about a fixed fulcrum.
A pin, in the slotted link, moves in proportion to its position along the slotted link.

https://en.wikipedia.org/wiki/Stephenson_valve_gear

 

[phinds]

Well, a super-fine-tooth rack and pinion would work.

 

[Nik_2213]

IIRC, there was a solution using eccentric to adjust height of 'Big End' centre, hence effective piston stroke.

You may find more inspiration for adjustable stroke among the 'variant' steam engines etc here...
http://www.douglas-self.com/MUSEUM/museum.htm
Note: As few such proved to be commercial successes, 'Due Care' advised...

 

[Baluncore]

Can you suggest the appropriate mechanism to achieve this adjustable motion?

The appropriate mechanism is the Stephenson valve gear, or a simple derivative of that. It gave steam engines every combination of variable valve timing from full forward to full reverse, all by moving one control lever. First applied in 1841, it is still in use today.

You do not need inspiration to reinvent something, you need only understand the Stevenson valve gear mechanism. It may look complicated when surrounded by an entire steam engine, but in any of its forms, the mechanism is really just a rocking bar that does the job.