Natural Motion for Energy Saving in Robotic and Mechatronic Systems

Energy saving in robotic and mechatronic systems is becoming an evermore important topic in both industry and academia. One strategy to reduce the energy consumption, especially for cyclic tasks, is exploiting natural motion. We define natural motion as the system response caused by the conversion of potential elastic energy into kinetic energy. This motion can be both a forced response assisted by a motor or a free response. The application of the natural motion concepts allows for energy saving in tasks characterized by repetitive or cyclic motion. This review paper proposes a classification of several approaches to natural motion, starting from the compliant elements and the actuators needed for its implementation. Then several approaches to natural motion are discussed based on the trajectory followed by the system, providing useful information to the researchers dealing with natural motion

An Overview on Principles for Energy Efficient Robot Locomotion

Despite enhancements in the development of robotic systems, the energy economy of today's robots lags far behind that of biological systems. This is in particular critical for untethered legged robot locomotion. To elucidate the current stage of energy efficiency in legged robotic systems, this paper provides an overview on recent advancements in development of such platforms. The covered different perspectives include actuation, leg structure, control and locomotion principles. We review various robotic actuators exploiting compliance in series and in parallel with the drive-train to permit energy recycling during locomotion. We discuss the importance of limb segmentation under efficiency aspects and with respect to design, dynamics analysis and control of legged robots. This paper also reviews a number of control approaches allowing for energy efficient locomotion of robots by exploiting the natural dynamics of the system, and by utilizing optimal control approaches targeting locomotion expenditure. To this end, a set of locomotion principles elaborating on models for energetics, dynamics, and of the systems is studied

Development and implementation of preventive-maintenance practices in Nigerian industries.

A methodology for the development of PM using the modern approaches of FMEA, root-cause analysis, and fault-tree analysis is presented. Applying PM leads to a cost reduction in maintenance and less overall energy expenditure. Implementation of PM is preferable to the present reactive maintenance procedures (still prevalent in Nigeria

Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 274)

This bibliography lists 128 reports, articles, and other documents introduced into the NASA scientific and technical information system in July 1985

Internationales Kolloquium über Anwendungen der Informatik und Mathematik in Architektur und Bauwesen : 20. bis 22.7. 2015, Bauhaus-Universität Weimar

The 20th International Conference on the Applications of Computer Science and Mathematics in Architecture and Civil Engineering will be held at the Bauhaus University Weimar from 20th till 22nd July 2015. Architects, computer scientists, mathematicians, and engineers from all over the world will meet in Weimar for an interdisciplinary exchange of experiences, to report on their results in research, development and practice and to discuss. The conference covers a broad range of research areas: numerical analysis, function theoretic methods, partial differential equations, continuum mechanics, engineering applications, coupled problems, computer sciences, and related topics. Several plenary lectures in aforementioned areas will take place during the conference. We invite architects, engineers, designers, computer scientists, mathematicians, planners, project managers, and software developers from business, science and research to participate in the conference

Adaptive Natural Oscillator to Exploit Natural Dynamics for Energy Efficiency

We present a novel adaptive oscillator, called Adaptive Natural Oscillator (ANO), to exploit the natural dynamics of a given robotic system. This tool is built upon the Adaptive Frequency Oscillator (AFO), and it can be used as a pattern generator in robotic applications such as locomotion systems. In contrast to AFO, that adapts to the frequency of an external signal, ANO adapts the frequency of reference trajectory to the natural dynamics of the given system. In this work, we prove that, in linear systems, ANO converges to the system's natural frequency. Furthermore, we show that this tool exploits the natural dynamics for energy efficiency through minimization of actuator effort. This property makes ANO an appealing tool for energy consumption reduction in cyclic tasks; especially in legged systems. We also extend the proposed adaptation mechanism to high dimensional and general cases; such as n-DOF manipulators. In addition, by investigating a hopper leg in simulation, we show the efficacy of ANO in face of dynamical discontinuities; such as those inherent in legged locomotion. Furthermore, we apply ANO to a simulated compliant robotic manipulator performing a periodic task where the energy consumption is drastically reduced. Finally, the experimental results on a 1-DOF compliant joint show that our adaptive oscillator, despite all practical uncertainties and deviations from theoretical models, exploits the natural dynamics and reduces the energy consumption

Neuromechanics and Augmentation of Muscle-Tendon Actuators in Unsteady Cyclic Tasks

Legged animals navigate complex environments with incredible stability, agility and economy despite having significant neuromechanical constraints like large delays and highly compliant actuators. They do so partly by tuning the mechanics of their actuators (i.e. muscle-tendon units) to act in a context-dependent manner. This raises several questions, three of which are discussed in this thesis. (A) to what extent can you purely rely on the mechanics of your actuators? In particular, can muscle-tendon units reject perturbations like uneven terrain without changing neural control? (B) how does stability, agility and economy vary with changing muscle-tendon properties individually and how do they tradeoff? and (C) if morphology affects movement performance in animals, can we augment human function across multiple objective functions (namely stability agility and economy) simultaneously by augmenting the morphology of muscle-tendon units with passive wearable robots. To answer these questions in a causal, controllable and generative manner, we developed a framework where a single muscle-tendon unit is interacting with a mass in gravity through a lever arm in closed loop to generate cyclic movement with variable terrain (both in simulation and in-vitro closed-loop experiments), variable morphology (in simulation) and variable nervous system control (in simulation). Through our work, we show that (A) muscle-tendon units can rapidly stabilize a hopping body when faced with a sudden change in ground height despite zero change in neural control, (B) series elastic tendons variably influence stability, agility and economy of movement such that animals need to trade off stability, agility and economy when tuning their muscle-tendon properties and (C) passive elastic exoskeletons are able to simultaneously augment stability, agility and economy despite being 'spring-like' and unable to do net work themselves by shifting the mechanics of underlying muscle-tendon units. Through our research, : (1) we gain fundamental neuromechanical understanding of how animals enable stable, agile and economic movement by tuning their actuators and (2) we generate a template for the design of a new generation of bioinspired robotic actuators to enable legged and wearable robots to navigate the world in all its richness and complexity.Ph.D