Robotics education: A case study in soft-bodied locomotion

Locomotion has been one of the frequently used case studies in hands-on curricula in robotics education. Students are usually instructed to construct their own wheeled or legged robots from modular robot kits. In the development process of a robot students tend to emphasize on the programming part and consequently, neglect the design of the robot's body. However, the morphology of a robot (i.e. its body shape and material properties) plays an important role especially in dynamic tasks such as locomotion. In this paper we introduce a case study of a tutorial on soft-robotics where students were encouraged to focus solely on the morphology of a robot to achieve stable and fast locomotion. The students should experience the influence material properties exert on the performance of a robot and consequently, extract design principles. This tutorial was held in the context of the 2012 Summer School on Soft Robotics at ETH Zurich, which was one of the world's first courses specialized in the emerging field. We describe the tutorial set-up, the used hardware and software, the students assessment criteria as well as the results. Based on the high creativity and diversity of the robots built by the students, we conclude that the concept of this tutorial has great potentials for both education and research. © 2013 IEEE.

Soft robotics: The next generation of intelligent machines

There has been an increasing interest in applying biological principles to the design and control of robots. Unlike industrial robots that are programmed to execute a rather limited number of tasks, the new generation of bio-inspired robots is expected to display a wide range of behaviours in unpredictable environments, as well as to interact safely and smoothly with human co-workers. In this article, we put forward some of the properties that will characterize these new robots: soft materials, flexible and stretchable sensors, modular and efficient actuators, self-organization and distributed control. We introduce a number of design principles; in particular, we try to comprehend the novel design space that now includes soft materials and requires a completely different way of thinking about control. We also introduce a recent case study of developing a complex humanoid robot, discuss the lessons learned and speculate about future challenges and perspectives.

Active roll control of an experimental articulated vehicle

A new experimental articulated vehicle with computer-controlled suspensions is used to investigate the benefits of active roll control for heavy vehicles. The mechanical hardware, the instrumentation, and the distributed control architecture are detailed. A simple roll-plane model is developed and validated against experimental data, and used to design a controller based on lateral acceleration feedback. The controller is implemented and tested on the experimental vehicle. By tilting both the tractor drive axle and the trailer inwards, substantial reductions in normalized lateral load transfer are obtained, both in steady state and transient conditions. Power requirements are also considered. © IMechE 2005.

Modular distributed manufacturing systems and the implications for integrated control

Driven by the need for more responsive manufacturing processes and as a consequence of increasing complexity in products and production systems, this short paper introduces a number of developments in the area of modular, distributed manufacturing systems. Requirements for the development of such systems are addressed and, in particular, the relevance to current and future integrated control systems is examined. One of the key issues for integrated control systems in the future is the need to provide support for distributed decision-making in addition to existing distributed control capabilities.

Comparison of stochastic methods for control in air traffic management

This paper provides a direct comparison of two stochastic optimisation techniques (Markov Chain Monte Carlo and Sequential Monte Carlo) when applied to the problem of conflict resolution and aircraft trajectory control in air traffic management. The two methods are then also compared to another existing technique of Mixed-Integer Linear Programming which is also popular in distributed control. © 2011 IFAC.

Control limitations from distributed sensing: Theory and Extremely Large Telescope application

We investigate performance bounds for feedback control of distributed plants where the controller can be centralized (i.e. it has access to measurements from the whole plant), but sensors only measure differences between neighboring subsystem outputs. Such "distributed sensing" can be a technological necessity in applications where system size exceeds accuracy requirements by many orders of magnitude. We formulate how distributed sensing generally limits feedback performance robust to measurement noise and to model uncertainty, without assuming any controller restrictions (among others, no "distributed control" restriction). A major practical consequence is the necessity to cut down integral action on some modes. We particularize the results to spatially invariant systems and finally illustrate implications of our developments for stabilizing the segmented primary mirror of the European Extremely Large Telescope. © 2013 Elsevier Ltd. All rights reserved.

Robust multiplexed MPC for distributed multi-agent systems

This paper extends the authors' earlier work which adapted robust multiplexed MPC for application to distributed control of multi-agent systems with non-interacting dynamics and coupled constraint sets in the presence of persistent unknown, but bounded disturbances. Specifically, we propose exploiting the single agent update nature of the multiplexed approach, and fix the update sequence to enable input move-blocking and increased discretisation rates. This permits a higher rate of individual policy update to be achieved, whilst incurring no additional computational cost in the corresponding optimal control problems to be solved. A disturbance feedback policy is included between updates to facilitate finding feasible solutions. The new formulation inherits the property of rapid response to disturbances from multiplexing the control and numerical results show that fixing the update sequence does not incur any loss in performance. © 2011 IFAC.

Data structures and software tools for the computer aided design of control systems: a survey.

CAD software can be structured as a set of modular 'software tools' only if there is some agreement on the data structures which are to be passed between tools. Beyond this basic requirement, it is desirable to give the agreed structures the status of 'data types' in the language used for interactive design. The ultimate refinement is to have a data management capability which 'understands' how to manipulate such data types. In this paper the requirements of CACSD are formulated from the point of view of Database Management Systems. Progress towards meeting these requirements in both the DBMS and the CACSD community is reviewed. The conclusion reached is that there has been considerable movement towards the realisation of software tools for CACSD, but that this owes more to modern ideas about programming languages, than to DBMS developments. The DBMS field has identified some useful concepts, but further significant progress is expected to come from the exploitation of concepts such as object-oriented programming, logic programming, or functional programming.