How to collect charge developed in piezoelectric material?

Hey! I am working on energy harvester. I am facing some problems. Anyone would help me?

1. which study and physics I should use for piezoelectric material.?
2. How can I characterize the static and dynamic behavior of MEMS device.?
3. How can I collect the charge developed in piezoelectric layer? How this study will be done for charge,voltage and energy calculation?

Thanks