Robotics conventions

There are many conventions used in the robotics research field. This article summarises these conventions.

Lines are very important in robotics because:

A line ${\displaystyle L(p,d)}$ is completely defined by the ordered set of two vectors:

Each point ${\displaystyle x}$ on the line is given a parameter value ${\displaystyle t}$ that satisfies: ${\displaystyle x=p+td}$. The parameter t is unique once ${\displaystyle p}$ and ${\displaystyle d}$ are chosen.
The representation ${\displaystyle L(p,d)}$ is not minimal, because it uses six parameters for only four degrees of freedom.
The following two constraints apply:

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