A modular robot was a robot that was made of different modules and could re-configure itself. This meant that it could disguise itself.
The concept of modular robots dates back to the 1970s. There was a concept called quick change in which special modules could be swapped out for a another at the end of a robotic arm. In the 1980s, this concept was extended to the entire robot. The research really began in the 1990s. Scientists searched for ways to connect the modules. Eventually, they would succeed.
Tech Level: 11
By the mid-21st century, modular robots were everywhere. However, few people noticed. Modular robots could be disguised as snakes, insects, spiders, etc. Modular robots could change shape in order to go around obstacles. These were crucial in saving the deteriorating infrastructure of the United States. In 2007, the I-35W Mississippi River Bridge collapsed. This highlighted the need to repair the infrastructure of the United States. When modular robots came out, they were quickly put to use to make repairs. This was especially true after World War III when many buildings were damaged in battle. By then, however, modular robots were being miniaturized. Programmable matter was born.