This paper introduces a new methodology to design modular industrial ultra-high precision robots; it aims at significantly reducing both the complexity of their design and their development time. This modular concept can be considered as a robotic Lego®, where a finite number of building bricks is used to quickly design the robot and to easily change its mobility. The core of the concept is the thorough conceptual solution catalogue, which is independent from any mechanical design. This paper will first present the methodology and the techniques to establish this solution catalogue. Then, its application to high precision will include the formulation of hypotheses and a practical example of a 5-degree of freedom ultra-high precision robot design.