How to convert Mechanical energy to electrical energy

There are transducers.It depends on where do you want to apply it i.e;Magnitude of force.
We can of course help you.Just tell us exactly "what project are you upto?"
give us more data.

A vehicle passing through a bump(speedbreaker) should be able to produce electricity. A small device can be put beneath the bump with a flat plate above-spring action-pressure on to the below plate etc.,

We cannot expect a transducer to be fitted beneath a speed breaker as speed breaker is a part of tar road.But it can be connected on the road.
Quartz crystal,load cells,strain gauge,piezoelectric,capacitance type transducers can perhaps solve the purpose.
But fitting it on a road is not a feasible idea as number of vehicles passing per unit time varies enormously.
We can perhaps fit it on vehicle itself and use that energy for lets say for an indicator or horn or charging battery etc
Any way nice question asked.Hope every one will contribute their knowledge for this thread.😁

transducers

A transducer is a device used as a sensor. It is defined as a device that experiences a related change when subject to a physical change. It ca be used as a sensor and for converting signals from one form to another in measurement. So as defined a transducer is a wide term. So just saying use a transducer is not very helpful.

For converting compressive/tensile force to a mechanical force, piezoelecric materials are best and have been used succesfully in a few places to generate electricity. When loaded, a piezoelectric material becomes positive on one face and the other face develops and equal and opposite charge (because of change in charge distribution)

Thanks Raj & Ishutrope for the information shared..