22 research outputs found
A vision-based teleoperation system for robotic systems
Despite advances in robotic perception are increasing autonomous capabilities, human intelligence is still considered a necessity in unstructured or unpredictable environments. Hence, also according to the Industry 4.0 paradigm, humans and robots are encouraged to achieve mutual Human-Robot Interaction (HRI). HRI can be physical (pHRI) or not, depending on the assigned task. For example, when the robot is constrained in a dangerous environment or must handle hazardous materials, pHRI is not recommended. In these cases, robot teleoperation may be necessary. A teleoperation system concerns with the exploration and exploitation of spaces where the user presence is not allowed. Therefore, the operator needs to move the robot remotely. Although plenty of human-machine interfaces for teleoperation have been developed considering a mechanical device, vision-based interfaces do not require physical contact with external devices. This grants a more natural and intuitive interaction, which is reflected in task performance. Our proposed system is a novel robot teleoperation system that exploits RGB cameras, which are easy to use and commonly available on the market at a reduced price. A ROS-based framework has been developed to supply hand tracking and hand-gesture recognition features, exploiting the OpenPose software based on the Deep Learning framework Caffe. This, in combination with the ease of availability of an RGB camera, leads the framework to be strongly open-source-oriented and highly replicable on all ROS-based platforms. It is worth noting that the system does not include the Z-axis control in this first version. This is due to the high precision and sensitivity required to robustly control the third axis, a precision that 3D vision systems are not able to provide unless very expensive devices are adopted. Our aim is to further develop the system to include the third axis control in a future release
A gesture-based robot program building software
With the advent of intelligent systems, industrial workstations and working areas have undergone a revolution. The increased need for automation is satisfied using high-performance industrial robots in fully automated workstations. In the manufacturing industry, sophisticated tasks still require human intervention in completely manual workstations, even if at a slower production rate. To improve the efficiency of manual workstations, Collaborative Robots (Co-Bots) have been designed as part of the Industry 4.0 paradigm. These robots collaborate with humans in safe environments to support the workers in their tasks, thus achieving higher production rates compared to completely manual workstations. The key factor is that their adoption relieves humans from stressful and heavy operations, decreasing job-related health issues. The drawback of Co-Bots stands in their design: to work side-by-side with humans they must guarantee safety; thus, they have very strict limitations on their forces and velocities, which limits their efficiency, especially when performing non-trivial tasks. To overcome these limitations, our idea is to design Meta-Collaborative workstations (MCWs), where the robot can operate behind a safety cage, either physical or virtual, and the operator can interact with the robot, either industrial or Collaborative, by means of the same communication channel. Our proposed system has been developed to easily build robot programs purposely designed for MCWs, based on (i) the recognition of hand gestures (using a vision-based communication channel) and (ii) ROS to carry out communication with the robot
New Materials and Technologies for Durability and Conservation of Building Heritage
The increase in concrete structures’ durability is a milestone to improve the sustainability of buildings and infrastructures. In order to ensure a prolonged service life, it is necessary to detect the deterioration of materials by means of monitoring systems aimed at evaluating not only the penetration of aggressive substances into concrete but also the corrosion of carbon-steel reinforcement. Therefore, proper data collection makes it possible to plan suitable restoration works which can be carried out with traditional or innovative techniques and materials. This work focuses on building heritage and it highlights the most recent findings for the conservation and restoration of reinforced concrete structures and masonry buildings
The Improvement of Durability of Reinforced Concretes for Sustainable Structures: A Review on Different Approaches
The topic of sustainability of reinforced concrete structures is strictly related with their durability in aggressive environments. In particular, at equal environmental impact, the higher the durability of construction materials, the higher the sustainability. The present review deals with the possible strategies aimed at producing sustainable and durable reinforced concrete structures in different environments. It focuses on the design methodologies as well as the use of unconventional corrosion-resistant reinforcements, alternative binders to Portland cement, and innovative or traditional solutions for reinforced concrete protection and prevention against rebars corrosion such as corrosion inhibitors, coatings, self-healing techniques, and waterproofing aggregates. Analysis of the scientific literature highlights that there is no preferential way for the production of “green” concrete but that the sustainability of the building materials can only be achieved by implementing simulta-neous multiple strategies aimed at reducing environmental impact and improving both durability and performances
Comparison of anticoagulation quality between acenocoumarol and warfarin in patients with mechanical prosthetic heart valves: Insights from the nationwide PLECTRUM study
Vitamin K antagonists are indicated for the thromboprophylaxis in patients with mechanical prosthetic heart valves (MPHV). However, it is unclear whether some differences between acenocoumarol and warfarin in terms of anticoagulation quality do exist. We included 2111 MPHV patients included in the nationwide PLECTRUM registry. We evaluated anticoagulation quality by the time in therapeutic range (TiTR). Factors associated with acenocoumarol use and with low TiTR were investigated by multivariable logistic regression analysis. Mean age was 56.8 ± 12.3 years; 44.6% of patients were women and 395 patients were on acenocoumarol. A multivariable logistic regression analysis showed that patients on acenocoumarol had more comorbidities (i.e., ≥3, odds ratio (OR) 1.443, 95% confidence interval (CI) 1.081-1.927, p = 0.013). The mean TiTR was lower in the acenocoumarol than in the warfarin group (56.1 ± 19.2% vs. 61.6 ± 19.4%, p < 0.001). A higher prevalence of TiTR (<60%, <65%, or <70%) was found in acenocoumarol users than in warfarin ones (p < 0.001 for all comparisons). Acenocoumarol use was associated with low TiTR regardless of the cutoff used at multivariable analysis. A lower TiTR on acenocoumarol was found in all subgroups of patients analyzed according to sex, hypertension, diabetes, age, valve site, atrial fibrillation, and INR range. In conclusion, anticoagulation quality was consistently lower in MPHV patients on acenocoumarol compared to those on warfarin
Hands-Free: A robot augmented reality teleoperation system
In this paper the novel teleoperation method Hands-Free is presented. Hands-Free is a vision-based augmented reality system that allows users to teleoperate a robot end-effector with their hands in real time. The system leverages OpenPose neural network to detect the human operator hand in a given workspace, achieving an average inference time of 0.15 s. The user index position is extracted from the image and converted in real world coordinates to move the robot end-effector in a different workspace.The user hand skeleton is visualized in real-time moving in the actual robot workspace, allowing the user to teleoperate the robot intuitively, regardless of the differences between the user workspace and the robot workspace.Since a set of calibration procedures is involved to convert the index position to the robot end-effector position, we designed three experiments to determine the different errors introduced by conversion. A detailed explanation of the mathematical principles adopted in this work is provided in the paper.Finally, the proposed system has been developed using ROS and is publicly available at the following GitHub repository: https://github.com/Krissy93/hands-free-project