Chetal Gazdar shows how you can create an aim constrain in Ae using a bit of expressions.
It’s astounding that an animation app like After Effects doesn’t have the native toolsets for the most basic animation workflows—for example, things like instancing, native IK, and constraints. If you want to have something like a constraint, you need to make one yourself or find a third-party tool.
Making an Aim Constraint With Expressions.
This new tutorial from Chetal Gazdar shows us how to use simple Trigonometry and After Effects Expressions to create a simple aim constraint. Some of us may not feel comfortable with the math involved, so Gazdar makes the project file available for download here.