NaturalMotion endorphin 

NaturalMotion endorphin is a powerful application that enables graphic designers to generate professional animated characters and scenes. This program makes it very easy to create all sorts of dynamic motions especially where there are human bodies involved. This application enables you to generate human bodies, special effects, transitions, environments, events, and visualize any change as you are applying them. It is also possible to load/save/import/export all your projects. All these tasks are done with the mouse only, although there are also many shortcut keys. In addition, this program offers you a comprehensive toolbox set for graphic design. This program lets you play your animation movies.

The user interface is very straightforward and easy to manage. You can find many sample videos, including a car crash, military scenes, fights, etc., that give an excellent approach to this program's capabilities. There is also an excellent tutorial. The developer offers a free version of the program that is called endorphin Learning Edition that also acts as a trial version for endorphin.