Mobile robotics is a solutions-oriented branch of industry that is rapidly developing, merging engineering sciences and information technology with such disciplines as cognitive sciences, Artificial Intelligence and many others. It is this interdisciplinary interplay that has made it possible to master the inherent complexity of mobile robots. Mobile robots are capable of independent movement and performing certain actions. Essentially, in addition to their mobility, they are able to function autonomously, without requiring human intervention. There is a general distinction between semi-autonomous and fully autonomous devices, based on the robot’s power supply; an external power supply, such as a charging station, has the effect of limiting autonomy.
Although the field of mobile robotics is currently at a relatively early stage of development, prototypes and even some serial products are starting to be found throughout a wide range of sectors. Mobile robotics has also found its way into everyday domestic applications with the invention of mobile vacuum cleaners, which are able to function with almost complete autonomy. Innovations made in the field of Artificial Intelligence and their applications are set to considerably enhance the future relevance and use of independent, mobile robots.
For many years, developments in robotics were primarily focused on the parameters of performance, repetition accuracy and speed. There are meanwhile additional criteria that are of just as great importance and serve the process of industrial transformation. The fundamental requirements of modern robots in virtually all sectors, particularly manufacturing, is that they must display flexibility, adaptability and, above all, autonomy. As these factors clearly show, industrial progress and development depend extensively on mobile robotics and automation technology. But it is not just the industrial sector that is benefiting from this trend - innovations in robotics are set to influence our lives in many other ways too in the future.
Although they display fundamental similarities, mobile robotics, having evolved out of existing systems, differs in many ways from classic robotics. Their central realignments and differences can be elucidated by comparing them with industrial robots. The sensory systems employed are in a profound state of transformation in terms of their relevance and scope of application. Because classic robots operate almost exclusively on the basis of a predetermined pattern, they do not display any operational independence. They do not require sensors, as there is only little uncertainty involved in their operation. In contrast, mobile robots rely essentially on a wide range of sensors, such as cameras, laser scanners, ultrasound, and other technologies. It is by incorporating such components that mobile robot systems are able to respond to spontaneously occurring events.
A further elementary distinction can be found in the way the robots are programmed. Mobile robotics is based on roles and can be considered task-oriented, while industrial robots run in accordance with an explicit software programme comprising a strict sequence of commands. A mobile device’s ability to plan and perform its movements independently is due to a combination of a complex sensory system and relatively free programming. A mobile robot’s sequence of movements is consequently guided by changes in the immediate environment, while traditional robots, as a rule, constantly repeat one and the same work process.
The stationary nature of conventional industrial robot installations means that they always operate within a known space that is subject to only minimal change. The whole point of mobile robots, however, is that they can vary they operation in accordance with their surroundings; as autonomous devices, they are able to independently explore new environments on the basis of their own perceptive and learning abilities. New information is subjected to further processing and is taken into account in future sequences of motion in the respective environment. The programmed ‘intelligence’ of mobile robots enables them to react spontaneously to events or even errors and, where possible, to locate alternative solutions. In similarly problematic situations, conventional industrial robots would simply discontinue their operation and emit an error signal.
In addition to software and control electronics, sensors and actuators are also essential components of any mobile robot system. The purpose of sensors is to obtain or ’sense’ a wide range of information and data that can be used for localisation and planning movements. Sensory systems installed inside a robot, such as voltage meters, thermometers, or radio signal receivers, provide information on the current system status. External sensors, installed on the surface of a mobile robot, such as push buttons, barcode readers, and torque and acceleration sensors, provide the system with the data it requires to perform its movement sequences.
Actuators are responsible for implementing control commands. They too act either internally or externally. Internal actuators affect the status of the system; for instance, the internal temperature can be regulated by fans and heaters. External actuators such as motors and pumps, on the other hand, serve to enable the robot to move or to allow the performance of activities by a manipulator such as a robotic arm.
The field of mobile robotics applications has a sheer unlimited breadth; thanks to the employment of intelligent technology in devices with independent operating ability, the latter can assume a wide range of uses. Applications are not limited to the production hall – mobile robots can now also be found in everyday situations, one example being semi-autonomous vacuum cleaners. Just like their traditional predecessors, they are used to pick up dirt from floors using a suction fan. However, unlike hand-controlled models, autonomous vacuum cleaners do not require any guidance from a human but follow a set of pre-programmed movement patterns; they are therefore able to react to obstacles such as steps, with the aid of sensors mounted to their underside. The only element posing a restriction to the devices’ autonomy is the power source.
In the context of industrial production, mobile robots are increasingly used for conveyance tasks. In a production facility, if certain materials are required by a machine for processing, or work pieces need to be taken into storage, specially equipped robots can be used to convey them. The modernisation of logistical structures and operations increases efficiency, reduces costs in the long term, and can even contribute to a safer working environment. As a link between individual work steps, mobile robotics has already become an important component of the so-called intelligent factory.
The areas of application of mobile robots also include terror prevention, disaster control and military use. Whether employed at the bottom of the sea, for defusing or clearing explosive devices, or as airborne drones – semi-autonomous robots are able to perform tasks that would be potentially dangerous to humans. Other application areas of mobile robotics include agriculture and public road transport, including self-driving motor vehicles.