So, you're interested in how a micromouse gets built? Although this is no manual, there are a few notes I can give.
As with any good engineering project, we must understand our problem. In this case, it's to build a robot to solve a maze. So, let's begin with how a robot can solve a maze.
How a mouse solves a maze is up to the designer. Many mice are programmed with learning algorithms to record their movement as they traverse the maze. As the mice record their movement, some are able to reduce longer paths to the center, or remember not to those longer paths. Depending on how the mice obtain their information on where the walls are, some mice are able to detect unnecessary paths before they enter it, and thus save otherwise wasted time in exploring useless areas of a maze. The ultimate goal of mice intelligence is twofold. The first is to find the shortest path from the start square to the center, while the second goal is to save exploration time by detecting and avoiding maze "traps" that waste time.
Building mice that can accurately and efficiently navigate through a maze is
a difficult task in its own right. Unless a mouse is mechanically solid, both
in design and construction, the longer the mouse is in the maze, the higher the
possibility the mouse can crash into something. Because of this, many designers
do not have time to implement a great deal of "intelligence" into
their mice, and thus leave them to wander in a maze, hoping they will find the
center without crashing.
One of the reasons it is very hard to build a mouse that can easily navigate a maze is the tracking that is necessary. As you all know, nothing is perfect. This includes motors, the method of locomotion of micromice. Depending on the terrain, one motor may slightly spin faster than the other. In addition, a motor can sometimes slip. At other times, their alignment becomes skewed. Furthermore, the sensors used to detect maze walls have their faults as well. Sensors can often miss walls, causing crashes. Sensors may also detect a "phantom" wall, causing a micromouse to see a false dead end.
Without getting too technical, those are just some of the fundamental issues involved in designing a working mouse.