Let's find out the Mechanical Efficiency of a simple machine, the Wedge.

What is a Wedge?

It is a machine to raise load like a screw jack. It consists of three sliding pairs. Frame(A), Wedge(W) and Sliders(S). When a force(F) is applied to the wedge, the slider is raised in the guides raising the load.

Mechanical efficiency of the wedge = 
Load raised when friction is considered/Load raised when friction is neglected 
​when the force applied is the same

Important parameters: 
Wedge Angle = 30° 
Coefficient of friction between between Slider(S) and Frame(A) = 0.105 
Coefficient of friction between between Slider(S) and Frame(W) = 0.141

💪Powers of Mechanical System Design(MSD)
✅ Contact (⭐ friction, collision, etc.)
✅ Gravity ⭐
✅ Axial Spring (⭐ with damping)
✅ Bushing 

💪Powers of Mechanical System Experience(MSE)
✅ Position Excitation
✅ Velocity Excitation
✅ Force Excitation
✅ Torque Excitation
✅ Sequence of Excitation
✅ Probes (⭐ position, speed, acceleration, joint force, etc.)
✅ Plots
✅ Traces

Recommended courses:
Practice CATIA Mechanical Systems Design
Practice CATIA Mechanical Systems Experience

Calculation of Mechanical Efficiency from Simulation data:

Case I: When friction is neglected

Force applied = 2 N

Load raised =  Weight of the wedge + Force on spring

where,

Weight of the wedge = Mass of Wedge * Acceleration due to gravity = 0.167 * 9.81 = 1.64 N

and Force on spring = 1.79 N (From the simulation)

Load raised = 1.64 + 1.79 = 3.43 N

Case II: When friction is considered

Force applied = 2 N

Load raised =  Weight of the wedge + Force on spring

where,

Weight of the wedge = Mass of Wedge * Acceleration due to gravity = 0.167 * 9.81 = 1.64 N

and Force on spring = 0.58 N (From the simulation)

Load raised = 1.64 + .58 = 2.25 N

Mechanical efficiency = 

load raised when friction is considered/Load raised when friction is neglected

= 2.25/3.43

= 0.66

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