Can anyone suggest any technical project for mechanical engineering?

Make a four legged robot vehicle as a substitute for two wheelers.

http://www.dtic.mil/dtic/tr/fulltext/u2/419858.pdf

https://www.google.co.in/search?q=low+cost+exoskeleton&ie=UTF-8&oe=UTF-8&hl=en-in&client=safari

How can I  do that?That means what is the idea and what is he concept?

If it is about the walker, then the concept is to replace rotary motion to linear.

If it is about the exoskeleton, it is a mobility aid for the disabled most of whom cannot afford the complex ones currently available.

You can also contact the Industrial Design Centre of IIT Bombay and check if they can guide an out station project. Some of their student projects can be seen here:

http://www.idc.iitb.ac.in/projects/student/project-areas.html

This list consists of the finest and most innovative major projects for the mechanical engineering final year.

• Enhanced Vertical Windmill System
• RF Controlled Beach Cleaner Robotic Vehicle 
• PLC Based Sorting System Using Metal Detection
• PLC Based Paper Cutting Machine