I am currently involved with a project using a mechanism similar to that seen in 'table tilters' and we are struggling to work out how to begin resolving the forces.
The image shows the state we are considering in equilibrium to resolve the forces. The plate (blue) is in a horizontal position and is 350mm in length
The linkages (red) are 270mm long and are at an angle of 20 degrees to the horizontal at this position.
The green component is restricted to motion in the vertical direction and is being pulled downwards with a force of 3000N.
We want to work out the downward force the linkages exert on the plate.
I started to try and break the system down into free body diagrams (below), but am struggling to make a start resolving the forces. Any advice would be greatly appreciated.