Modular robots represent a major technological challenges in the last decades because of expectations on their massive use in our lifetime, particularly in order to improve the well-being of people. Indeed, modular robots are gaining increasing attention due to their use in various missions and tasks in a wide range of applications, including location, the fight against fires, medical services, surveillance and security, and search and rescue. They can perform tasks in unstructured environments, complex, dynamic and unknown. To carry out these missions robots must apply reconfiguration protocols to adapt to working conditions. These reconfiguration protocols must deal with the limitations of nodes including those relating to memory and energy resources. Also, these algorithms should be effective, scalable, secure and robust, using only local information. In this paper, we provide a review on the recent protocols that achieve the self-reconfigurations without predefined positions of the target shape.Modular robots, reconfiguration, MEMS, Mapless.