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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Elektrický lanový kladkostroj / Electrical cabel hoist

Rada, Aleš January 2008 (has links)
This diploma thesis deals with the electgrical cabel hoist 5t,which will be placed in the hall. The aim of the calculating and draving documentation is to design and make control of drivers and travel. , machine components of travel height including the calculation and choice of steel rope. In material design I come out not only from CSN and german DIN standars , but also literature, which deals of cranes.
2

Low effort patient handling devices.

Waymouth, Andrew David January 2014 (has links)
With an aging population there is a growing need to assist people with disabilities. Particularly crucial is assisting people who cannot stand between positions necessary for everyday living, such as from a wheelchair to the toilet. It is unsafe to transfer people with direct manual techniques, thus a patient handling device is required. To reduce the burden on the healthcare system it is beneficial for disabled people to be cared for in-home. Many in-home caregivers may be physically impaired, thus patient handling devices for this use must require as little effort as possible. This thesis found that existing manual patient handling devices contained significant weaknesses when used for in-home care and there is potential to improve upon them. Expert interviews, computer modelling and physical models were used to develop a novel patient handling device which addresses these identified weaknesses. A reduction in the number of operator tasks, operation time and operation force was achieved. A method of supporting the patient solely by their upper body is required by the novel patient handling device, though an acceptable way of incorporating this has yet to be achieved. Testing of an upper body enclosure support revealed that a person may be supported by their lower thorax without substantial clamping or physical effort from the patient. Such a support has potential to be developed into an acceptable solution. Further development and testing in variable conditions encountered during practical patient handling is required.
3

Modélisation et optimisation des Hoist Scheduling Problems / Modeling and Optimization for Hoist Scheduling Problems

Feng, Jianguang 24 August 2017 (has links)
Dans cette thèse, nous étudions des Hoist Scheduling Problems (HSP) qui se posent fréquemment dans des lignes automatiques de traitement de surface. Dans ces lignes, des ponts roulants sont utilisés pour transporter les pièces entre les bains. Ainsi, les ponts roulants jouent un rôle essentiel dans la performance de ces lignes ; et un ordonnancement optimal de leurs mouvements est un facteur déterminant pour garantir la qualité des produits et maximiser la productivité. Les lignes que nous étudions comportent un seul pont roulant mais peuvent être des lignes de base ou des lignes étendues (où des bains sont à fonctions et/ou capacités multiples). Nous examinons trois Hoist Scheduling Problems : l’optimisation robuste d’un HSP cyclique, l’ordonnancement dynamique d’une ligne étendue de type job shop et l’ordonnancement cyclique d’une telle ligne.Pour l’optimisation robuste d’un HSP cyclique, nous définissons la robustesse comme la marge dans le temps de déplacement du pont roulant. Nous formulons le problème en programmation linéaire en nombres mixtes à deux objectifs pour optimiser simultanément le temps de cycle et la robustesse. Nous démontrons que le temps de cycle minimal augmente avec la robustesse, et que par conséquent la frontière Pareto est constituée d’une infinité de solutions. Les valeurs minimales et maximales des deux objectifs sont établies. Les résultats expérimentaux à partir de benchmarks et d’instances générées aléatoirement montrent l’efficacité de l’approche proposée.Nous étudions ensuite un problème d’ordonnancement dynamique dans une ligne étendue de type job shop. Nous mettons en évidence une erreur de formulation dans une un modèle existant pour un problème similaire mais sans bains multi-fonctions. Cette erreur peut rendre l’ordonnancement obtenu sous-optimal voire irréalisable. Nous construisons un nouveau modèle qui corrige cette erreur. De plus il est plus compact et s’applique au cas avec des bains à la fois à capacités et à fonctions multiples. Les résultats expérimentaux menés sur des instances avec ou sans bains multi-fonctions montrent que le modèle proposé conduit toujours à une solution optimale et plus efficace que le modèle existant.Nous nous focalisons enfin sur l’ordonnancement cyclique d’une ligne étendue de type job shop avec des bains à fonctions et capacités multiples. Nous construisons un modèle mathématique en formulant les contraintes de capacité du pont roulant, les intervalles des durées opératoires, et les contraintes de capacité des bains. Nous établissons également des contraintes valides. Les expériences réalisées sur des instances générées aléatoirement montrent l’efficacité du modèle proposé. / This thesis studies hoist scheduling problems (HSPs) arising in automated electroplating lines. In such lines, hoists are often used for material handing between tanks. These hoists play a crucial role in the performance of the lines and an optimal schedule of the hoist operations is a key factor in guaranteeing product quality and maximizing productivity. We focus on extended lines (i.e. with multi-function and/or multi-capacity tanks) with a single hoist. This research investigates three hoist scheduling problems: robust optimization for cyclic HSP, dynamic jobshop HSP in extended lines and cyclic jobshop HSP in extended lines.We first study the robust optimization for a cyclic HSP. The robustness of a cyclic hoist schedule is defined in terms of the free slacks in hoist traveling times. A bi-objective mixed-integer linear programming (MILP) model is developed to optimize the cycle time and the robustness simultaneously. It is proved that the optimal cycle time strictly increases with the robustness, thus there is an infinite number of Pareto optimal solutions. We established lower and upper bounds of these two objectives. Computational results on several benchmark instances and randomly generated instances indicate that the proposed approach can effectively solve the problem.We then examine a dynamic jobshop HSP with multifunction and multi-capacity tanks. We demonstrate that an existing model for a similar problem can lead to suboptimality. To deal with this issue, a new MILP model is developed to generate an optimal reschedule. It can handle the case where a multi-function tank is also multi-capacity. Computational results on instances with and without multifunction tanks indicate that the proposed model always yields optimal solutions, and is more compact and effective than the existing one.Finally, we investigate a cyclic jobshop HSP with multifunction and multi-capacity tanks. An MILP model is developed for the problem. The key issue is to formulate the time-window constraints and the tank capacity constraints. We adapt the formulation of time-window constraints for a simpler cyclic HSP to the jobshop case. The tank capacity constraints are handled by dealing with the relationships between hoist moves so that there is always an empty processing slot for new parts. Computational experiments on numerical examples and randomly generated instances indicate that the proposed model can effectively solve the problem.
4

Design aktivního zvedáku pro hendikepované / Design of an active Patient Lift

Štigler, Jaroslav January 2018 (has links)
The topic of this thesis is the Design of an active patient lift. This project brings new ideas into the patient lift design problematice while using plastic molds. Overall plastic cover is the solution for agresive looks of current products. From the technical point of view this project combines current technologies into the new, so far nonexisting, solution. Thesis brings new views on lifts controls and movement while considering ergonomic and technological parameters.
5

Pomocné zařízení pro manipulaci s osobním vozidlem / Accessory Equipment For Passenger Car Manipulation

Buryšek, Adam January 2011 (has links)
This master’s thesis deals about equipment for manipulation with passenger car. It represents a summary of present equipment and engineering design of such devices. The purpose of this thesis is to make more efficient work with passenger cars for the ÚADI needs.
6

Jeřáb mostový jednonosníkový / Bridge crane one-girder

Malár, Martin January 2014 (has links)
This master’s thesis is focused on the construction design of one-girder bridge crane for the LUVE – PLAST company. Construction design of the crane was developed in cooperation with the K-TECHNIK company, which carried out the production and installation of the crane bridge and the crane runway. The basic required parameters of the crane are: load capacity 8 000 kg, range 16 900 mm, minimum lift 4 650 mm. The crane, which construction is proposed in this thesis will be used for the exchange of forms of injection molding machines. The forms weight is about 7 000 kg. The aim of this work was to create a technical report with an analysis of construction choices solution with important technical and strength calculations. Calculations were made according to the Czech state standards and the literature dealing with the construction of bridge cranes. Further, the strength check of selected parts was made.
7

Sloupový jeřáb pro manipulaci s plechy / Jib crane for handling metal plates

Dobšíček, Tomáš January 2012 (has links)
This diploma thesis deals with the construction design of revolving column crane which is used for manipulation with metal plates for metal shears and bending bench. The aim is to set main proportions and basic parameters for the designed steel construction via design calculation. Then the thesis deals with checking of strength analysis done by programme I-DEAS NX 11. Suggestion of disposal placement of the crane, choice of hoist, travelling system, auxiliary device and drawing documentation are also parts of the design.
8

A dual hoist robot crane for large area sensing

Harber, John A. 27 May 2016 (has links)
Cranes are used to lift and move large objects in a wide variety of applications at constructions sites, shipping ports, and manufacturing facilities, etc. If the load to be moved is too long or heavy for a single crane, then two, or more, cranes must work in cooperation to move the payload. In a factory setting this can be accomplished using two trolleys running along the same bridge forming a dual hoist crane. Using two hoists not only increases lifting capacity, it also improves stability of the payload over traditional single hoist configurations. This research takes advantage of that increased stability and explores a novel application for dual hoist cranes: suspending a robot arm from the two trolleys. This increases the workspace of the robot to the entirety of the space covered by the crane, opening up numerous applications not possible with a stationary robot. In order to better understand and characterize the dynamics of the system, a numerical model was developed and tested against a physical system to confirm its validity. A vision system has the potential to greatly increase the usefulness of a robotic system such as the one presented in previous paragraph. The Asus Xtion was used in this work due to its versatility and low cost. An evaluation of this sensor was performed. Various tests were conducted to determine its accuracy in a range of scenarios. It was found that crane oscillations degraded the quality of data returned. This is effect is especially detrimental if the crane is moved to a specified point and sensing begins immediately. The data collection process could be delayed until the residual oscillations subside, however the time penalty incurred by waiting is large because the oscillations are lightly damped and have a long period. To address this issue a control method called input shaping was introduced to reduce the residual oscillations thereby increasing the quality of the sensor data. Finally, two promising uses of the robot arm dual-hoist crane system were introduced: painting and sandblasting. The efficiency of a factory equipped with this system can be increased at relatively low cost by automating manual tasks such as these.
9

Ordonnancement des ateliers de traitement de surface pour une production cyclique et mono-produit

Mangione, Fabien 17 July 2003 (has links) (PDF)
Cette thèse traite des lignes de traitement de surface qui sont des lignes dans lesquelles les pièces sont immergées dans une succession de cuves. Chaque cuve contient des bains qui affectent les propriétés mécaniques ou électriques des pièces. Ce type de ligne est utilisé, par exemple, pour la galvanoplastie. Les pièces sont montées sur des porteurs et transportées d'une cuve à l'autre par un robot. Le temps opératoire (ou temps pendant lequel la pièce reste dans la cuve) est borné. La borne inférieure est le temps minimum qui permet le traitement et la borne supérieure dépend du type de traitement (attaque acide, rinçage...).<br />Un objectif classique est de trouver les mouvements du robot qui maximisent la productivité, ce problème est communément appelé “hoist scheduling problem” (HSP). Lors de ce travail nous nous sommes attachés à une production cyclique. Nous avons proposé dans le cas d'une ligne à deux cuves une méthode permettant d'obtenir les cycles optimaux. Nous avons démontré, pour le cas d'une ligne équilibrée à trois cuves pour une production mono-produit, les caractéristiques des cycles optimaux ainsi qu'une méthode pour les obtenir. Ensuite, nous avons étudié le problème sur quatre machines dans le cas où les temps de trempe sont égaux et sans attente. Nous avons proposé les cycles optimaux dans le cas d'une production mono-produit. Enfin nous avons proposé une conjecture sur les cycles optimaux et en avons démontré certaines parties, dans le cas d'une ligne équilibrée avec un nombre de cuves quelconque et où les marges sur les temps de process sont nulles.
10

Mostový jeřáb - návrh jeřábové kočky / Overhead crane - design of crane trolley

Brzobohatý, Petr January 2010 (has links)
The diploma work deals with design of lifting mechanism of overhead crane trolley with a load capacity 200 t. The main objective is design and analysis of selected components of lifting mechanism and components which are directly associated with lifting mechanism. Work includes design elements of a rope system, such as rope, rope drum, sheaves, sheave block, elements of the proposals of propulsion, such as engine, transmission, brake, coupling. The work contains also strength calculations of some components and drawing documentation.

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