关键词： actuators   fibers   fabrics   power sources   sensors   soft robotics  

摘要： Soft robotics inspired by the movement of living organisms, with excellent adaptability and accuracy for accomplishing tasks, are highly desirable for efficient operations and safe interactions with human. With the emerging wearable electronics, higher tactility and skin affinity are pursued for safe and user-friendly human-robot interactions. Fabrics interlocked by fibers perform traditional static functions such as warming, protection, and fashion. Recently, dynamic fibers and fabrics are favorable to deliver active stimulus responses such as sensing and actuating abilities for soft-robots and wearables. First, the responsive mechanisms of fiber/fabric actuators and their performances under various external stimuli are reviewed. Fiber/yarn-based artificial muscles for soft-robots manipulation and assistance in human motion are discussed, as well as smart clothes for improving human perception. Second, the geometric designs, fabrications, mechanisms, and functions of fibers/fabrics for sensing and energy harvesting from the human body and environments are summarized. Effective integration between the electronic components with garments, human skin, and living organisms is illustrated, presenting multifunctional platforms with self-powered potential for human-robot interactions and biomedicine. Lastly, the relationships between robotic/wearable fibers/fabrics and the external stimuli, together with the challenges and possible routes for revolutionizing the robotic fibers/fabrics and wearables in this new era are proposed.

关键词： buckling   mechanical instabilities   programmable matter   snap through   soft robotics  

摘要： The rapidly expanding field of soft robotics has provided multiple examples of how entirely soft machines and actuators can outperform conventional rigid robots in terms of adaptability, maneuverability, and safety. Unfortunately, the soft and flexible materials used in their construction impose intrinsic limitations on soft robots, such as low actuation speeds and low output forces. Nature offers multiple examples where highly flexible organisms exploit mechanical instabilities to store and rapidly release energy. Guided by these examples, researchers have recently developed a variety of strategies to overcome speed and power limitations in soft robotics using mechanical instabilities. These mechanical instabilities provide, through rapid transitions from structurally stable states, a new route to achieve high output power amplification and attain impressive actuation speeds. Here, an overview of the literature related to the development of soft robots and actuators that exploit mechanical instabilities to expand their actuation speed, output power, and functionality is presented. Additionally, strategies using structural phase transitions to address current challenges in the area of soft robotic control, sensing, and actuation are discussed. Approaches using instabilities to create entirely soft logic modules to imbue soft robots with material intelligence and distributed computational capabilities are also reviewed.

关键词： Legged robot   Leg hydraulic drive system (LHDS)   Dynamics compensation   Impedance based motion control  

摘要： Aimed at the negative effect of dynamics characteristics of leg hydraulic drive system (LHDS) on the accuracy of motion control of the hydraulic drive legged robot, a dynamics compensation control method is proposed. First, according to the mechanical structure of LHDS, the kinematics and statics models of LHDS are analyzed and obtained respectively. Based on the principle of force-based impedance control of LHDS, an impedance based motion control simulation model of LHDS is built and analyzed. The simulation results show that the dynamics characteristics have a great influence on the accuracy of impedance based motion control. Then, a dynamics compensation method considering gravity and inertia force is proposed to solve this problem. Finally, the effect of the dynamics compensation method is verified on the robot single leg test platform. The experimental results show that the compensation method reduces the negative effect of the dynamics characteristics of LHDS on impedance based motion control accuracy, and the position tracking accuracy of the robot's foot end can be improved by more than 65%. The theory proposed in this paper provides a theoretical basis for the motion control of the whole robot prototype. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Free energy  

摘要： Predictive processing has become an influential framework in cognitive sciences. This framework turns the traditional view of perception upside down, claiming that the main flow of information processing is realized in a top-down, hierarchical manner. Furthermore, it aims at unifying perception, cognition, and action as a single inferential process. However, in the related literature, the predictive processing framework and its associated schemes, such as predictive coding, active inference, perceptual inference, and free-energy principle, tend to be used interchangeably. In the field of cognitive robotics, there is no clear-cut distinction on which schemes have been implemented and under which assumptions. In this letter, working definitions are set with the main aim of analyzing the state of the art in cognitive robotics research working under the predictive processing framework as well as some related nonrobotic models. The analysis suggests that, first, research in both cognitive robotics implementations and nonrobotic models needs to be extended to the study of how multiple exteroceptive modalities can be integrated into prediction error minimization schemes. Second, a relevant distinction found here is that cognitive robotics implementations tend to emphasize the learning of a generative model, while in nonrobotics models, it is almost absent. Third, despite the relevance for active inference, few cognitive robotics implementations examine the issues around control and whether it should result from the substitution of inverse models with proprioceptive predictions. Finally, limited attention has been placed on precision weighting and the tracking of prediction error dynamics. These mechanisms should help to explore more complex behaviors and tasks in cognitive robotics research under the predictive processing framework.

关键词： Hopping robot   Hopping-height control   Energy control   Energy   phase control  

摘要： Hopping height control is one of the difficult problems in legged control. Many kinds of research employ a leg spring for the supplement of energy, and model the robot as a spring-mass model. Feedback linearization enables to cancel the nonlinear terms theoretically. However, it is difficult to identify the nonlinear terms including the parameters precisely in the real world. This paper nominalizes the robot dynamics as the desired spring-mass system applying a disturbance observer. In order to realize the desired characteristics of the spring and the mass, the disturbance including the nonlinear terms is rejected firstly by a disturbance observer. To make the mass in the workspace as constant, the nominal inertia of the disturbance observer in the joint space is varied. Next, by adding the desired virtual elastic force, the robot dynamics is nominalized as the desired spring-mass system. Based on the nominalized spring-mass dynamics, hopping-height control using energy/phase control is implemented. While energy control is often used for hopping height control, the energy/phase control enables the hopping-height control and the spring-mass oscillation simultaneously. Constant hopping-height and stepwise hopping height are realized experimentally through the proposed control method. The simulations in the case of the ideal dynamics are also conducted for comparison.

关键词： Spatial variables control   Aerospace control   Control system analysis and synthesis methods   Stability in control theory   Self-adjusting control systems   Nonlinear control systems  

摘要： This paper presents the design, analysis, and implementation of an adaptive backstepping controller for underactuated quadrotors to track time-varying trajectories with parameter uncertainties. Quadrotor systems are subject to complicated non-linearity and coupling dynamics, so the ignorance of parameter uncertainties may cause performance degradation and even instability. With the concept of nominal input, the uncertain mass and inertia are decoupled from the lifting force and moment torque. By utilizing the backstepping technique, the design procedure with adaptive laws for dynamic parameters is proposed to ensure stability and convergence of tracking errors to the origin asymptotically. The proposed control scheme is extended to control a quadrotor with velocity motor input while the motor coefficients and geometric parameters are handled by the adaptive laws. A trajectory generation for the proposed adaptive tracking controller is addressed subsequently. The proposed controller requires only the position and orientation of the quadrotor with the twice-differentiable trajectories, while previous work demanded acceleration information. Simulation and experimental results are illustrated to show the efficacy of tracking performance for object transportation.

关键词： dentistry   robots   robotics  

摘要： Robotics is a disruptive technology that will change diagnostics and treatment protocols in dental medicine. Robots can perform repeated workflows for an indefinite length of time while enhancing the overall quality and quantity of patient care. Early robots required a human operator, but robotic systems have advanced significantly over the past decade, and the latest medical robots can perform patient intervention or remote monitoring autonomously. However, little research data on the therapeutic reliability and precision of autonomous robots are available. The present paper reviews the promise and practice of robots in dentistry by evaluating published work on commercial robot systems in dental implantology, oral and maxillofacial surgery, prosthetic and restorative dentistry, endodontics, orthodontics, oral radiology as well as dental education. In conclusion, this review critically addresses the current limitations of dental robotics and anticipates the potential future impact on oral healthcare and the dental profession.

关键词： robot industry   medical robotics   technology commercialization   data mining  

摘要： The robot industry is a key field of the Fourth Industrial Revolution. Among them, the interest in medical robotics is increasing due to aging and changes in living patterns. In the medical robotics market, a small number of companies dominate the market, causing problems such as increased costs. To prevent such problems, various companies need to enter the market. In order for new entrants to secure technology efficiently, technology commercialization such as technology transfer is necessary. However, in the field of medical robotics, few companies have major skills and perform most of the technology transfer. In this paper, we propose a model for providing technology commercialization information to new entrants. The experimental data uses patents related to vascular surgery robots registered in the USPTO. As a result of the experiment, high applicants have advanced into various countries in order to secure market power, and have a technique for analyzing the internal image of the body mainly through endoscopy.

关键词： High-throughput technology   Enzyme technology   Drug delivery   Nanobot   Biofuel  

摘要： The use of robotics in the life science sector has created a considerable and significant impact on a wide range of research areas, including enzyme technology due to their immense applications in enzyme and microbial engineering as an indispensable tool in high-throughput screening applications. Scientists are experiencing the advanced applications of various biological robots (nanobots), fabricated based on bottom-up or top-down approaches for making nanotechnology scaffolds. Nanobots and enzyme-powered nanomotors are particularly attractive because they are self-propelled vehicles, which consume biocompatible fuels. These smart nanostructures are widely used as drug delivery systems for the efficient treatment of various diseases. This review gives insights into the escalating necessity of robotics and nanobots and their ever-widening applications in enzyme technology, including biofuel production and biomedical applications. It also offers brief insights into high-throughput robotic platforms that are currently being used in enzyme screening applications for monitoring and control of microbial growth conditions.