33,096 research outputs found
Autonomous Construction with Compliant Building Material
In this paper, we develop an autonomous construction system in which a self-contained ground robot builds a protective barrier by means of compliant pockets (i.e., filled bags). We present a stochastic control algorithm based on two biological mechanisms (stigmergy and templates) that takes advantage of compliant pockets for autonomous construction. The control algorithm guides the robot to build the structure without relying on any external motion capture system or external computer. We propose a statistical model to represent the structures built with the compliant pockets, and we provide a set of criteria for assessing the performance of the proposed system. To demonstrate the feasibility of the proposed system, real-robot experiments were carried out. In each experiment, the robot successfully built the structure. The results show the viability of the proposed autonomous construction system
Design of an Anthropomorphic, Compliant, and Lightweight Dual Arm for Aerial Manipulation
This paper presents an anthropomorphic, compliant and lightweight dual arm manipulator designed and developed for aerial manipulation applications with multi-rotor platforms. Each arm provides four degrees of freedom in a human-like kinematic configuration for end effector positioning: shoulder pitch, roll and yaw, and elbow pitch. The dual arm, weighting 1.3 kg in total, employs smart servo actuators and a customized and carefully designed aluminum frame structure manufactured by laser cut. The proposed
design reduces the manufacturing cost as no computer numerical control machined part is used. Mechanical joint compliance is provided in all the joints, introducing a compact spring-lever transmission mechanism between the servo shaft and the links, integrating a potentiometer for measuring the deflection of the joints.
The servo actuators are partially or fully isolated against impacts and overloads thanks to the ange bearings attached to the frame structure that support the rotation of the links and the deflection of the joints. This simple mechanism increases the robustness of the arms and safety in the physical interactions between the aerial
robot and the environment. The developed manipulator has been validated through different experiments in fixed base test-bench and in outdoor flight tests.Unión Europea H2020-ICT-2014- 644271Ministerio de EconomÃa y Competitividad DPI2015-71524-RMinisterio de EconomÃa y Competitividad DPI2017-89790-
Adaptive locomotion of artificial microswimmers
Bacteria can exploit mechanics to display remarkable plasticity in response
to locally changing physical and chemical conditions. Compliant structures play
a striking role in their taxis behavior, specifically for navigation inside
complex and structured environments. Bioinspired mechanisms with rationally
designed architectures capable of large, nonlinear deformation present
opportunities for introducing autonomy into engineered small-scale devices.
This work analyzes the effect of hydrodynamic forces and rheology of local
surroundings on swimming at low Reynolds number, identifies the challenges and
benefits of utilizing elastohydrodynamic coupling in locomotion, and further
develops a suite of machinery for building untethered microrobots with
self-regulated mobility. We demonstrate that coupling the structural and
magnetic properties of artificial microswimmers with the dynamic properties of
the fluid leads to adaptive locomotion in the absence of on-board sensors
Quick-cast: A method for fast and precise scalable production of fluid-driven elastomeric soft actuators
Fluid-driven elastomeric actuators (FEAs) are among the most popular
actuators in the emerging field of soft robotics. Intrinsically compliant, with
continuum of motion, large strokes, little friction, and high power-to-weight
ratio, they are very similar to biological muscles, and have enabled new
applications in automation, architecture, medicine, and human-robot
interaction. To foster future applications of FEAs, in this paper we present a
new manufacturing method for fast and precise scalable production of complex
FEAs of high quality (leak-free, single-body form, with <0.2 mm precision). The
method is based on 3d moulding and supports elastomers with a wide range of
viscosity, pot life, and Young's modulus. We developed this process for two
different settings: one in laboratory conditions for fast prototyping with 3d
printed moulds and using multi-component liquid elastomers, and the other
process in an industrial setting with 3d moulds micromachined in metal and
applying compression moulding. We demonstrate these methods in fabrication of
up to several tens of two-axis, three-chambered soft actuators, with two types
of chamber walls: cylindrical and corrugated. The actuators are then applied as
motion drivers in kinetic photovoltaic building envelopes
A modern day panopticon: using power and control theory to manage volunteer tourists in Bolivia
Volunteer tourism literature is yet to examine the impact of power and control practices on volunteer tourist compliancy. This paper contributes to closing this research gap by proposing and testing a new theoretical model of power and control practices. Drawing upon the previously un-synthesized theoretical contributions of Foucault (1979) and French & Raven (1959), the model presents power and control practices identified in the extant organizational literature. Using an auto-ethnographic approach, data was collected within a Bolivian volunteer-host community. Examination of results suggested mutually beneficial volunteer-host working relationships occur under ‘softer’ management practices. Our findings also offer insight into the salience of using reward-based management strategies as a control mechanism, as well as identifying two new control practices that emerged empirically. The research suggests several implications for the management of host communities towards creating more harmonious, efficient, and effective working relationships between volunteer tourists and hosts
The Problem of Adhesion Methods and Locomotion Mechanism Development for Wall-Climbing Robots
This review considers a problem in the development of mobile robot adhesion
methods with vertical surfaces and the appropriate locomotion mechanism design.
The evolution of adhesion methods for wall-climbing robots (based on friction,
magnetic forces, air pressure, electrostatic adhesion, molecular forces,
rheological properties of fluids and their combinations) and their locomotion
principles (wheeled, tracked, walking, sliding framed and hybrid) is studied.
Wall-climbing robots are classified according to the applications, adhesion
methods and locomotion mechanisms. The advantages and disadvantages of various
adhesion methods and locomotion mechanisms are analyzed in terms of mobility,
noiselessness, autonomy and energy efficiency. Focus is placed on the physical
and technical aspects of the adhesion methods and the possibility of combining
adhesion and locomotion methods
- …