The next exploratory stage in robotics is the humanoid robot, which has actualized the earlier cultivated walking research areas. Robots that walk in a human-like manner are a fascinating topic of the research. The potential benefits range from service robots, robots for entertainment, mathematical study for controlling of complex dynamical systems to knowledge for the restoration of damaged human locomotion. This research topic also involves many fields such as Biomechanics, Robotics, Physiology, Orthopedics, Psychology, Neurosciences, Sport, Computer Graphics and Applied Mathematics. The walking algorithms are well researched and multiply demonstrated. The newly arisen actuality of the field is due to the recent questioning of the earlier approaches, by demonstrating the passive dynamic walking mechanisms. This naturally raised expectation for utilizing like ideas for the energy efficient walking. Actuated dynamic walking as opposite to the passive dynamic walking is meant to make the mechanism controllable while the mechanism itself is constructed so that the effects making the passive dynamic walking possible would as much as possible contribute to an energy efficient bipedal locomotion. From these the objectives, our research can be directly inferred since practically no such device has been effectively demonstrated yet, though in theory it is very much doable. The reason for this is that with no previously employed approaches this task is possible. First of all, no satisfactory mechanisms have been built or proposed, secondly, the very much plausible control ideas have not yet been extended to such cases. The development processes of the bipedal mechanisms have been stuck, and basically are all alike. Anthropomorphism in the mechanism design have been raised but not yet solved.
In the Aalto University Department of Automation and Systems Technology, one of the main research topics is service robotics. Service robots are aimed to provide services to humans instead of manufacturing purposes. For instance, they shall autonomously carry out monotonous, dangerous or tedious tasks. Crucial prerequisites for performing services are mobility and autonomy. On flat surfaces, wheels are most efficient however for rough terrain or the typical human environment, the leg locomotion is more advantageous. The control of bipeds is usually more complicated, but they are more flexible in their motion and better adapted to the human environment. The hope of service robotics would be to put robots into new environments that have never before been explored, or into old ones which are hostile to humans. There are also obvious practical benefits to using walking robots for many natural environments that would increase the productivity of such application, for example: they are one of the smallest of all the locomotion robots, easy to carry around and requiring less energy, can access areas that other robots cannot like ladders or very narrow paths and they do not require change in the working environment since they use the same kind of locomotion humans use. Lately in service robotics the main attention has been redirected to the long time autonomy of the mobile robotics platforms. For that, much effort has been made to develop new more efficient electrical powered service robots, aiming to increase their productivity substantially. In that matter, the increase of energy efficiency also reduces environmental impacts that can help industries to fulfill new and stricter environmental regulation applied worldwide. To accomplish the previous tasks one of the main challenges is to obtain an efficient dynamic bipedal locomotion, which will provide a more useful walking robot in real life applications, as opposed to the static form of locomotion demonstrated by most of the current prototypes. A promising concept is the idea of passive dynamic walking where even completely unactuated and uncontrolled mechanisms can perform a stable gait when walking down a small slope. This concept could enable the construction of dynamically walking prototypes that are simpler yet more natural and efficient in their motions than the static bipeds.
For more information: Peter Jakubik (concept, design and project lead)
José Luis Peralta