Human sensor Robot

Hi,

I'm working on a project on which i want create a little robot which will react to an order which is to detect a person and come to make a contact with her, like just push her gently.

The robot is on a table and the person will have arms on the table so it may be not that hard to detect her.

I'm searching for a easy issue because i just start arduino.

Thanks for any suggestion.

the question is more about the way to detect the person or her arms

the question is more about the way to detect the person or her arms

A specific person? Or any warm body?

I din't really know it's better to detetc person, but yes it may be a warm body as it would be the warmest body on the table i guess.

Any suggestions on detect human or warm body ?