Search results for "Roboti"
showing 10 items of 687 documents
New Expression of the Hydraulic Jump Roller Length
2012
AbstractThis paper presents the results of an experimental investigation on the roller length of both classical and B-jumps on smooth beds. Using the measurements conducted in this investigation and those available in the literature, a new relationship is proposed for estimating the roller length of classical and B-jumps on smooth beds. Finally, it is demonstrated that the proposed equation is also applicable to estimate the roller length of hydraulic jumps on rough horizontal beds.
A New Quasi-Static Cylindrical Roller Bearing Model to Accurately Consider Non-Hertzian Contact Pressure in Time Domain Simulations
2012
The accuracy of the fatigue life calculations in rolling bearing simulations is highly dependent on the precision of the roller-raceway contact simulations. Several different methods exist to simulate these pressure distributions and in time domain bearing simulations, where many contacts need evaluation, the simple and time efficient methods are more popular, yielding erroneous life estimates. This paper presents a new six degree of freedom frictionless quasi-static time domain cylindrical roller bearing model that uses high precision elastic half-space theory to simulate the contact pressures. The potentially higher computational demand using the advanced contact calculations is addressed…
Design optimization on the drive train of a light-weight robotic arm
2011
A drive train optimization method for design of light-weight robots is proposed. Optimal selections of motors and gearboxes from a limited catalog of commercially available components are done simultaneously for all joints of a robotic arm. Characteristics of the motor and gearbox, including gear ratio, gear inertia, motor inertia, and gear efficiency, are considered in the drive train modeling. A co-simulation method is developed for dynamic simulation of the arm. A design example is included to demonstrate the proposed design optimization method.
Adaptive interaction robot control with estimation of contact force
2008
Abstract This paper deals with a new adaptive force-position control of a robotic manipulator based on force estimation. First, an adaptive position controller is derived with contact force component as estimated parameters. Second, a supervisory external loop is added in order to regulate the contact force to the desired value. Extensive simulations with 2-DOF manipulator illustrate the followed approach.
Robustness Analysis of an Extended Kalman Filter for Sensorless Control of Induction Motors
2010
This paper deals with robustness analysis of Extended Kalman Filters (EKFs) for sensorless motion control of induction motors. Analysis is carried out by means of simulation experiments considering a conventional EKF, in which system and measurement noise covariance matrices are constant, and an adaptive EKF in which the system noise covariance matrix is updated on-line using a PID-type algorithm driven by the stator current estimation errors.
SmartLeg: An intelligent active robotic prosthesis for lower-limb amputees
2011
In recent years, there has been a worldwide interest in improvement of mobility of people with lower limb amputation. In spite of significant development of new technologies during the last decade, commercial below-knee and above-knee prostheses are still energetically passive devices. However, many locomotive functions, like walking up stairs and slopes, need significant power in knee and ankle joints. The additional power for doing previously mentioned activities needs to be achieved by means of external energy sources, which should be integral prosthetic components. This paper presents preliminary investigations towards an active robotic prosthesis that could potentially enable people wi…
ROAD project: Robotics for assisted diving
2014
The activities associated to underwater diving are of great importance in many areas. In the second half of the last century, diving technologies have greatly progressed, but diving is still characterized by significant risks, especially for professional divers who works at high depth, and limited practicability. The use of robotic systems and automatic procedures would allow, as in other situations where safety is of concern (for example, in case of hazardous works or in relation to hostile environments), a reliable monitoring and assessment of the physiological conditions of human operators during their activities. Moving from currently available technologies in underwater robotics, the R…
Visual Behaviour Based Bio-Inspired Polarization Techniques in Computer Vision and Robotics
2012
For long time, it was thought that the sensing of polarization by animals is invariably related to their behavior, such as navigation and orientation. Recently, it was found that polarization can be part of a high-level visual perception, permitting a wide area of vision applications. Polarization vision can be used for most tasks of color vision including object recognition, contrast enhancement, camouflage breaking, and signal detection and discrimination. The polarization based visual behavior found in the animal kingdom is briefly covered. Then, the authors go in depth with the bio-inspired applications based on polarization in computer vision and robotics. The aim is to have a comprehe…
A New HLA-Based Distributed Control Architecture for Agricultural Teams of Robots in Hybrid Applications with Real and Simulated Devices or Environme…
2011
The control architecture is one of the most important part of agricultural robotics and other robotic systems. Furthermore its importance increases when the system involves a group of heterogeneous robots that should cooperate to achieve a global goal. A new control architecture is introduced in this paper for groups of robots in charge of doing maintenance tasks in agricultural environments. Some important features such as scalability, code reuse, hardware abstraction and data distribution have been considered in the design of the new architecture. Furthermore, coordination and cooperation among the different elements in the system is allowed in the proposed control system. By integrating …
Assistive robotic walker parameter identification for estimation of human thrust without force sensors
2017
In this paper we propose a parameter identification procedure for the wheel-motor dynamic of a robotic walker, i.e. a commercial trolley for elderly people endowed with cognitive, sensing and guidance capabilities. The objective of the wheel-motor dynamic model is to generate a suitable time reference to be used in an estimation algorithm. The ultimate goal of the estimation algorithm is to retrieve the thrust, i.e. torque and force, that the older adult user of the robotic walker applies to the platform. These quantities are of paramount importance in order to adopt intelligent and comfortable walker guidance algorithms. The novelty of this approach is the avoidance of additional costly se…