413 research outputs found
Robotic Picking of Tangle-prone Materials (with Applications to Agriculture).
The picking of one or more objects from an unsorted pile continues to be non-trivial for robotic systems. This is especially so when the pile consists of individual items that tangle with one another, causing more to be picked out than desired. One of the key features of such tangling-prone materials (e.g., herbs, salads) is the presence of protrusions (e.g., leaves) extending out from the main body of items in the pile.This thesis explores the issue of picking excess mass due to entanglement such as occurs in bins composed of tangling-prone materials (TPs), especially in the context of a one-shot mass-constrained robotic bin-picking task. Specifically, it proposes a human-inspired entanglement reduction method for making the picking of TPs more predictable. The primary approach is to directly counter entanglement through pile interaction with an aim of reducing it to a level where the picked mass is predictable, instead of avoiding entanglement by picking from collision or entanglement-free points or regions. Taking this perspective, several contributions are presented that (i) improve the understanding of the phenomenon of entanglement and (ii) reduce the picking error (PE) by effectively countering entanglement in a TP pile.First, it studies the mechanics of a variety of TPs improving the understanding of the phenomenon of entanglement as observed in TP bins. It reports experiments with a real robot in which picking TPs with different protrusion lengths (PLs) results in up to a 76% increase in picked mass variance, suggesting PL be an informative feature in the design of picking strategies. Moreover, to counter the inherent entanglement in a TP pile, it proposes a new Spread-and-Pick (SnP) approach that significantly reduces entanglement, making picking more consistent. Compared to prior approaches that seek to pick from a tangle-free point in the pile, the proposed method results in a decrease in PE of up to 51% and shows good generalisation to previously unseen TPs
SMA-Based Muscle-Like Actuation in Biologically Inspired Robots: A State of the Art Review
New actuation technology in functional or "smart" materials has opened new horizons in robotics actuation systems. Materials such as piezo-electric fiber composites, electro-active polymers and shape memory alloys (SMA) are being investigated as promising alternatives to standard servomotor technology [52]. This paper focuses on the use of SMAs for building muscle-like actuators. SMAs are extremely cheap, easily available commercially and have the advantage of working at low voltages.
The use of SMA provides a very interesting alternative to the mechanisms used by conventional actuators. SMAs allow to drastically reduce the size, weight and complexity of robotic systems. In fact, their large force-weight ratio, large life cycles, negligible volume, sensing capability and noise-free operation make possible the use of this technology for building a new class of actuation devices. Nonetheless, high power consumption and low bandwidth limit this technology for certain kind of applications. This presents a challenge that must be addressed from both materials and control perspectives in order to overcome these drawbacks. Here, the latter is tackled. It has been demonstrated that suitable control strategies and proper mechanical arrangements can dramatically improve on SMA performance, mostly in terms of actuation speed and limit cycles
Unconventional Cognitive Intelligent Robotic Control: Quantum Soft Computing Approach in Human Being Emotion Estimation -- QCOptKB Toolkit Application
Strategy of intelligent cognitive control systems based on quantum and soft
computing presented. Quantum self-organization knowledge base synergetic effect
extracted from intelligent fuzzy controllers imperfect knowledge bases
described. That technology improved of robustness of intelligent cognitive
control systems in hazard control situations described with the cognitive
neuro-interface and different types of robot cooperation. Examples demonstrated
the introduction of quantum fuzzy inference gate design as prepared
programmable algorithmic solution for board embedded control systems. The
possibility of neuro-interface application based on cognitive helmet with
quantum fuzzy controller for driving of the vehicle is shown
Design and analysis of a novel long-distance double tendon-sheath transmission device for breast intervention robots under MRI field
Cancer represents a major threat to human health. Magnetic resonance imaging (MRI) provides superior performance to other imaging-based examination methods in the detection of tumors and offers distinct advantages in biopsy and seed implantation. However, because of the MRI environment, the material requirements for actuating devices for the medical robots used in MRI are incredibly demanding. This paper describes a novel double tendon-sheath transmission device for use in MRI applications. LeBus grooves are used in the original transmission wheels, thus enabling the system to realize long-distance and large-stroke transmission with improved accuracy. The friction model of the transmission system and the transmission characteristics model of the novel tendon-sheath structure are then established. To address the problem that tension sensors cannot be installed in large-stroke transmission systems, a three-point force measurement method is used to measure and set an appropriate preload in the novel tendon-sheath transmission system. Additionally, experiments are conducted to verify the accuracy of the theoretical model and multiple groups of tests are performed to explore the transmission characteristics. Finally, the novel tendon-sheath transmission system is compensated to improve its accuracy and the experimental results acquired after compensation show that the system satisfies the design requirements
RF communication between surface and underwater robotic swarms
In order for underwater robots to communicate with land and air based robots on an equal basis, high speed communications is required. If the robots are not to be tethered then wireless communications is the only possibility. Sonar communications is too slow. Unfortunately radio waves are rapidly attenuated under water due to phenomena such as skin depth. These experiments attempt to extend the range of underwater radio communications.<br /
Autonomous biomimitic robot based multi-agent system for disaster management and rescue
This paper discusses the scope and feasibility of autonomous biomimitic robot based multi-agent
systems for disaster management and rescue. Search and rescue operations in disastrous situations
like earthquake, landslide, fire hazards, mineshaft breakdown etc. are still handled manually. Manual
operations in these cases often fail due to complicated nature of the catastrophe. Especially in the
case of human entrapment in areas inaccessible to either human or traditional rescue equipment. As
such rescue operation suffers from improper strategy and even leads to unintentional further
destruction due to lack of proper information along the rescue site. It is clear, proper information in
and around the disaster can help successful handling of the catastrophe. Thus information like
location of the survivor, state of the obstructions around him/her, state of injury, level of oxygen and
hazardous gases are of crucial importance. To gather such widespread information from such difficult
terrain, autonomous robots equipped with multiple sensors and capable to move inside difficult to
access areas is a good choice.
Autonomous biomimitic robot like Snake robot is meant to mimic motion of a natural snake, which
does not possess any limb. Natural snakes can undergo wide range of motion and are able to move
over rough terrains without the danger of entanglement. Slender structure of the snake body helps a
snake to go inside narrow holes. Thus a snake robot able to mimic these features of a natural snake
will be of extreme use in handling search and rescue operations. Snake robots equipped with multiple
sensors and controlled under multiagent collaborative protocol are expected to bring about acceptable
solution to disaster management and rescue. The other such biomimitic robots that can be considered
in the autonomous robot team are flapping wing flyers and robot Monkeys. A team consisting of such
robots will help in collecting information, distributing food and medicine in disastrous location
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