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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

Autonomous bucket emptying on hauler

Bergdahl, Anders January 2011 (has links)
This thesis proposes a method of loading a hauler with an autonomous wheelloader efficiently and with high productivity in the short loading cycle. The mainidea behind the method is to raise the bucket with only the lift until the centerof gravity has reached the height that it will have just as the material will startto fall out of the bucket and on to the hauler. When the center of gravity hasreached that height both lift and tilt will be used simultaneously to keep thecenter of gravity at a constant height. This method is both faster and moreenergy efficient than loading a hauler using only one function at a time. The method has been successfully implemented and validated by loading ahauler with three buckets with the autonomous wheel loader that is developed byVolvo CE in Eskilstuna. / autonomous wheel loader VolvoCE
2

Automatic bucket fill

Almqvist, Håkan January 2009 (has links)
<p>This report contains the first step towards a complete, fully autonomous, robust bucket fill regulator for a wheel loader working with gravel materials.</p><p>The bucket fill procedure is the most critical part of the work cycle of a wheel loader. It is a task that has a long learning curve and also is weary, even for experienced drivers. The automation of it could therefore have a big impact on the cost effectiveness for wheel loaders and for the comfort of the drivers.</p><p>In this report, a suggestion for the complete solution of an automatic bucket fill regulator is presented. A regulator prototype is also constructed with a Volvo L120F as the base. The scope for the prototype is limited to one type of gravel material and quite optimal conditions for the wheel loader, but the complete solution is kept in mind throughout the synthesis. The constructed regulator is prepared for expansion, but the implementation and field testing is limited to the scope.</p>
3

Automatic bucket fill

Almqvist, Håkan January 2009 (has links)
This report contains the first step towards a complete, fully autonomous, robust bucket fill regulator for a wheel loader working with gravel materials. The bucket fill procedure is the most critical part of the work cycle of a wheel loader. It is a task that has a long learning curve and also is weary, even for experienced drivers. The automation of it could therefore have a big impact on the cost effectiveness for wheel loaders and for the comfort of the drivers. In this report, a suggestion for the complete solution of an automatic bucket fill regulator is presented. A regulator prototype is also constructed with a Volvo L120F as the base. The scope for the prototype is limited to one type of gravel material and quite optimal conditions for the wheel loader, but the complete solution is kept in mind throughout the synthesis. The constructed regulator is prepared for expansion, but the implementation and field testing is limited to the scope.
4

Körbarhetskvantifiering av Hjullastare

Stener, Patrik, Snabb, Robert January 2008 (has links)
<p>Idag är det möjligt att modellera de hydrauliska och mekaniska systemen hos en hjullastare. Det går även i viss omfattning att simulera omgivningen samt de förarkommandon som krävs för utförandet av en önskad uppgift. Däremot är det enda sättet att få reda på hur en förare kommer att uppleva maskinen, dess körbarhet, att bygga en fungerande prototyp och be en förare att testa den.</p><p>Syftet med det här examensarbetet var att hitta en korrelation mellan förarens bedömningar och mätdata insamlade från en hjullastare under körning. Resultaten är sedan tänkta att användas i framtida simuleringar. Olika hjullastare testades av en grupp provförare och deras subjektiva bedömningar såväl som mätdata från hjullastarna samlades in.</p><p>Slutsatsen är att det går till en viss del att förutsäga körbarheten från insamlade data om förarens körstil är känd. Då förarnas körstil skiljer väldigt mycket är det är inte möjligt att dra allmänna slutsatser om körbarheten.</p> / <p>Today it is possible to model all hydraulic and mechanical systems of a wheel loader. To an extent the surrounding environment and the operator input required for a desired operation can also be simulated. However the only way to determine how an operator will perceive the handling qualities, the operability, of the wheel loader is to assemble a working prototype and ask an operator to try it out.</p><p>The purpose of this Master thesis was to find some correlation between the drivers’ opinions and data recorded from the machines during operation. The results are intended to be used in future simulations. Different machines were tested by a group of drivers and their subjective impressions, as well as measurements from the machines were collected.</p><p>The findings from the analysis are that the operability can be determined to a certain extent if the driver’s behaviour is known. Because of the differences in the way the drivers operate the machine it has not been possible to draw any general conclusions.</p>
5

Embedded Instrument Panel for Construction Equipment / Glass Cockpit

Linder, Rickard, Lagerholm, Lars January 2012 (has links)
Construction equipment such as wheel loaders and dumpers are constantly getting updated with new technology when it comes to performance and fuel consumption. But the interior in the cockpit has not been exposed to any dramatic changes for decades. A modernized cockpit gives the driver a more modern feel of driving a highly technological machine, while at the same time enables for personalization. This thesis work presents a new way of improving the look and feel for displaying relevant information and also relaying information to both the driver of the machine and spectators outside. It includes a way of rerouting CAN-bus signals from a construction machine and displaying it on a tablet. The core idea with the solution is to make it as modular as possible to further improve and be able to use it in any machine available at Volvo's disposal. With this in mind, any machine could use the same software, the same hardware and still be able to fully utilize all the features that have been implemented from the thesis work. The idea and implementational results are designed as partly embedded and partly towards user interface.
6

Implementation of a Pump Control System for a Wheel Loader Application / Implementation av styrsystem för pumpstyrning i en hjullastare

Gunnarsson, Daniel, Strid, Emanuel January 2007 (has links)
<p>A lot of today’s new developments strive for energy efficiency. This includes the hydraulic side of industry. The Division of Fluid andMechanical Engineering Systems of Linköpings University in collaboration with Volvo Construction Equipment in Eskilstuna has developed a newhydraulic concept when it comes to the control of cylinder loads in a wheel loader. The concept differs from today’s application, where the cylinderload is controlled via a valve, in the way that the load is solely controlled by a pump. To control this system, an electrical feed back of operatorsdemanded signal is needed. These signals have to be correctly interpreted so that valve and the pumps perform the requested operation. The newsystem is going to need a unit that can perform these operations in a way that corresponds to the operating level of today’s hydraulically controlledsystem.The study aims to develop a software platform that solves this. This platform shall, besides performing the operators’ demands, monitor the system.The monitoring of the system is a crucial part because of security issues, but also when analyzing the systems functionality. The implementation ofthis software will be done in a real-time computer with the ability to collect data, interpret it and then control the connected units of the system.Further work that is to be done is an energy consumption study of today’s hydraulic system, and on the basis of this study, theoretically evaluate thenew system.The study has resulted in a great insight of an industrial mechanic machine, this in a level that includes an entire system. The wide range of thistask has brought analysis and development of both hydraul mechanical-, electrical- and software related systems. With an understanding of these,both separate and in interaction with each other, a platform has been designed that shall facilitate the forthcoming development of energy efficienthydraulics, both at VCE and LiTH.</p>
7

Fysikalisk modellering av klimat i entreprenadmaskin / Physical Modeling of Climate in Construction Vehicles

Nilsson, Sebastian January 2005 (has links)
<p>This masters thesis concerns a modeling project performed at Volvo Technology in Gothenburg, Sweden. The main purpose of the project has been to develop a physical model of the climate in construction vehicles that later on can be used in the development of an electronic climate controller. The focus of the work has been on one type of wheel loader and one type of excavator. The temperature inside the compartment has been set equal to the notion climate. </p><p>With physical theories about air flow and heat transfer in respect, relations between the components in the climate unit and the compartment has been calculated. Parameters that has had unknown values has been estimated. The relations have then been implemented in the modeling tool Simulink. </p><p>The validation of the model has been carried out by comparison between measured data and modeled values by calculation of Root Mean Square and correlation. Varying the estimated parameters and identifying the change in the output signal, i.e the temperature of the compartment, have performed a sensitivity analysis. </p><p>The result of the validation has shown that the factor with the greatest influence on the temperature in the vehicle is the airflow through the climate unit and the outlets. Minor changes of airflow have resulted in major changes in temperature. The validation principally shows that the model gives a good estimation of the temperature in the compartment. The static values of the model differs from the values of the measured data but is regarded being as within an acceptable margin of error. The weakness of the model is mainly its predictions of the dynamics, which does not correlate satisfyingly with the data.</p>
8

Development of Parking Brake Component : Product Development and Mechanical Design Process

Rintamäki, Julia January 2013 (has links)
This report represents the bachelor thesis examination by Julia Kastehelmi Rintamäki. The examination has been performed during spring semester 2013 at Volvo Construction Equipment in Eskilstuna. This report, Development of parking brake component, describes the product development process of the parking brake component for articulated hauler, wheel loader and grader. Volvo CE has problems with the parking brake switch that exist today on articulated hauler, wheel loader and grader. The purpose of this project is to develop one common solution for the parking brake component for articulated hauler, wheel loader and grader. The secondary purpose is to find final concept proposal for each machine. Employees at the Volvo CE were interviewed; they were contacted via e-mail, phone calls and via meetings to get the information about the machines and the information around the parking brake component. Volvo CE databases were also used for gathering information about standards and pictures. Lots of different ideas were sketched and concept proposals were created with the aid of material from marketing analysis, competitor analysis, target group analysis, requirement specification, function analysis, standards and ergonomics. Eight concept proposals were chosen to be evaluated with QFD, Pugh’s matrix and FMEA. Two concepts were most suitable and developed further to three dimensional models with the aid of Solid Works. The different aspects were taken into account when designing and dimensioning the final concepts. Two models were created with the aid of plasticine for figuring out the ergonomics and dimensions of the product. DFM, DFA, DFE, D4S were used for taking into account costs, assembly, dimensions and environmental impacts of this product. One of the concepts could replace the existing parking brake switch and suit in different cabins because of its size and design. This concept can be located on vertical or on horizontal plane. The other final concept solution functions better for the  articulated hauler on account of the double function with exhausting brake system activating before parking brake system. Suggestion for next steps for the project could be to make prototypes of the two concepts and test these components in real machines. Also interviewing users for further development of the final concepts and redesign if needed.
9

Implementation of a Pump Control System for a Wheel Loader Application / Implementation av styrsystem för pumpstyrning i en hjullastare

Gunnarsson, Daniel, Strid, Emanuel January 2007 (has links)
A lot of today’s new developments strive for energy efficiency. This includes the hydraulic side of industry. The Division of Fluid andMechanical Engineering Systems of Linköpings University in collaboration with Volvo Construction Equipment in Eskilstuna has developed a newhydraulic concept when it comes to the control of cylinder loads in a wheel loader. The concept differs from today’s application, where the cylinderload is controlled via a valve, in the way that the load is solely controlled by a pump. To control this system, an electrical feed back of operatorsdemanded signal is needed. These signals have to be correctly interpreted so that valve and the pumps perform the requested operation. The newsystem is going to need a unit that can perform these operations in a way that corresponds to the operating level of today’s hydraulically controlledsystem.The study aims to develop a software platform that solves this. This platform shall, besides performing the operators’ demands, monitor the system.The monitoring of the system is a crucial part because of security issues, but also when analyzing the systems functionality. The implementation ofthis software will be done in a real-time computer with the ability to collect data, interpret it and then control the connected units of the system.Further work that is to be done is an energy consumption study of today’s hydraulic system, and on the basis of this study, theoretically evaluate thenew system.The study has resulted in a great insight of an industrial mechanic machine, this in a level that includes an entire system. The wide range of thistask has brought analysis and development of both hydraul mechanical-, electrical- and software related systems. With an understanding of these,both separate and in interaction with each other, a platform has been designed that shall facilitate the forthcoming development of energy efficienthydraulics, both at VCE and LiTH.
10

Fysikalisk modellering av klimat i entreprenadmaskin / Physical Modeling of Climate in Construction Vehicles

Nilsson, Sebastian January 2005 (has links)
This masters thesis concerns a modeling project performed at Volvo Technology in Gothenburg, Sweden. The main purpose of the project has been to develop a physical model of the climate in construction vehicles that later on can be used in the development of an electronic climate controller. The focus of the work has been on one type of wheel loader and one type of excavator. The temperature inside the compartment has been set equal to the notion climate. With physical theories about air flow and heat transfer in respect, relations between the components in the climate unit and the compartment has been calculated. Parameters that has had unknown values has been estimated. The relations have then been implemented in the modeling tool Simulink. The validation of the model has been carried out by comparison between measured data and modeled values by calculation of Root Mean Square and correlation. Varying the estimated parameters and identifying the change in the output signal, i.e the temperature of the compartment, have performed a sensitivity analysis. The result of the validation has shown that the factor with the greatest influence on the temperature in the vehicle is the airflow through the climate unit and the outlets. Minor changes of airflow have resulted in major changes in temperature. The validation principally shows that the model gives a good estimation of the temperature in the compartment. The static values of the model differs from the values of the measured data but is regarded being as within an acceptable margin of error. The weakness of the model is mainly its predictions of the dynamics, which does not correlate satisfyingly with the data.

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