“…cos(δ), are zero, which could stop backpropagation learning at the extreme opposite output. To resolve this problem, researchers [50,51,52,53,54,55,56,57,58,59,60,61] performed regression on both the cosine and sine of the angle (cos(θ), sin(θ)). When converting any given 1D Scalar-Based Orientation θ into 2-Dimensional values, they can be mapped to 2-D Cartesian system with angle's cosine value projected to x-axis and sine value projected to y-axis.…”