Pedal Triangles
By Raynold Gilles.
Definition.
In geometry, a pedal triangle is obtained by projection. It is constructed by joining the feet of the altitudes of a triangle.
After several investigations using GSP we made the following conclusions.

The pedal triangle moves as as the pedal point is moved.

The pedal point can be inside or oustide the triangle.

There is a special case when the pedal triangle collapses into a line called the Simpson Line. This special case occurs when the pedal point is on the circumcircle.
Further investigation can be accomplished by clicking on the srcipt tool below.
Pedal.