Kinematics of a particle moving on a curve

Binormal:

The binormal is the line that passes through the point P and is perpendicular to the osculating plane.

The figure above shows a binormal vector, which is the cross-product of unit tangent vector and principal normal.

With these concepts, we will develop an expression for the acceleration of a partical moving on a space curve.

Let us carry out the derivative needed in equ(1) from the basic definition.