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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.
191

Predictive control for autonomous driving : With experimental evaluation on a heavy-duty construction truck

Lima, Pedro January 2016 (has links)
Autonomous vehicles is a rapidly expanding field, and promise to play an important role in society. In more isolated environments, vehicle automation can bring significant efficiency and production benefits and it eliminates repetitive jobs that can lead to inattention and accidents. The thesis addresses the problem of lateral and longitudinal dynamics control of autonomous ground vehicles with the purpose of accurate and smooth path following. Clothoids are used in the design of optimal predictive controllers aimed at minimizing the lateral forces and jerks in the vehicle. First, a clothoid-based path sparsification algorithm is proposed to efficiently describe the reference path. This approach relies on a sparseness regularization technique such that a minimal number of clothoids is used to describe the reference path. Second, a clothoid-based model predictive controller (MPCC) is proposed. This controller aims at producing a smooth driving by taking advantage of the clothoid properties.  Third, we formulate the problem as an economic model predictive controller (EMPC). In EMPC the objective function contains an economic cost (here represented by comfort or smoothness), which is described by the second and first derivatives of the curvature.  Fourth, the generation of feasible speed profiles, and the longitudinal vehicle control for following these, is studied. The speed profile generation is formulated as an optimization problem with two contradictory objectives: to drive as fast as possible while accelerating as little as possible. The longitudinal controller is formulated in a similar way, but in a receding horizon fashion. The experimental evaluation with the EMPC demonstrates its good performance, since the deviation from the path never exceeds 30 cm and in average is 6 cm. In simulation, the EMPC and the MPCC are compared with a pure-pursuit controller (PPC) and a standard MPC. The EMPC clearly outperforms the PPC in terms of path accuracy and the standard MPC in terms of driving smoothness. / <p>QC 20160503</p> / iQMatic
192

System Design of Automated Test Equipment for Electrical Control Units in Trucks

Bladh, Anna January 2014 (has links)
The high level of complexity in today’s electronic systems increases the demands on an advanced validation and verification process. Automated testing facilitates and improves regression testing (rerun of previously executed test cases to uncover and track new bugs) with increased coverage and reduced costs as a result.  A vehicle contains multiple control units, each responsible for a specific part: the engine, brakes, gearbox etc. These intelligent systems must be tested thoroughly to ensure correct behavior - both under normal circumstances and when the vehicle is exposed to unexpected events such as electrical failure (short circuit, broken cables etc.). A breakout box, BOB, is a piece of testing equipment that can be used to induce electrical faults on the wiring of the control units. It is typically operated manually. The objective of this project is to develop an automated version, an ABOB.  A prototype that could induce various faults on arbitrary cables of a control unit was developed. The faults were: short circuit to a variable voltage source with connected or disconnected load, replacement of real signals with simulated ones and open load. The breakout box also performed internal measurements and supplied the user with feedback information about whether or not the test case was successfully executed. Several generations of the system were developed, where the final product had hardware support for up to six connected ECU ports and the possibility to distribute control signals to 256 different ECU ports via a computer based application and a set of communicating microprocessors.  This thesis project focuses on the software design of the ABOB. For further explanation of the hardware, the reader is advised to consult the report Hardware Synthesis of Automated Electrical Fault Testing in Trucks by Martin Orre. / Komplexiteten i dagens elektroniska system ställer höga krav på verifierings- och valideringsmetoder. Testautomatisering underlättar och förbättrar regressionstestning (upprepning av tidigare utförda testfall för att upptäcka och spåra nya buggar) med ökad testtäckning och reducerade kostnader som följd.  I ett fordon sitter ett flertal styrenheter vars ansvarsområden varierar: styrning utav motor, bromsar, växellåda osv. För att säkra att dessa enheter fungerar som de ska måste de testas noggrant - dels under normala förhållanden men också då de utsätts för påfrestningar såsom elektriska fel (kortslutning, avbrott osv.). En breakout box, BOB, är en typ av testutrustning vars syfte är att inducera fel på kablaget till styrenheter. Den sköts vanligtvis manuellt. Syftet med det här projektet är att ta fram en automatiserad breakout box, en ABOB.  En prototyp som kunde inducera ett antal olika fel på godtyckliga kablar kopplade till en styrenhet togs fram. Felen var: kortslutning mot en variabel spänningskälla, simulering av en felaktig signal samt avbrott på kabel. Systemet hade också en återkopplingsmekanism som informerade användaren om huruvida ett testfall hade exekverats på korrekt sätt eller ej. Ett flertal generationer av hård- och mjukvarulösningar utvecklades, där den slutgiltiga produkten hade hårdvarustöd för upp till sex inkopplade ECU-portar och möjlighet att via en datorbaserad applikation samt ett nät av kommunicerande mikroprocessorer distribuera styrsignaler till upp till 256 ECU-portar.  Detta examensarbete behandlar framtagningen av mjukvara för systemet. Den intresserade läsaren rekommenderas att även ta del av rapporten Hardware Synthesis of Automated Electrical Fault Testing in Trucks av Martin Orre, för kompletterande information om hårdvaran.
193

Organising the internal transport to increase lift trucks utilisation : A case study at a large manufacturing company

Ogbatzion, Meron January 2022 (has links)
The purpose of this thesis is to analyse the internal transport of a case company and develop a new approach to increase the utilisation rate of their lift trucks. The case study was conducted at a large manufacturing company in southern Sweden and limited to two of their production facilities, denoted PVT and Tage, with a total of 27 lift trucks. The current data provided by the case company imposed limitations on decision-making since it only specified the total number of hours each truck was used in a year. By mapping out the current material handling processes at both facilities, opportunities were identified on how the internal transport can be organised in an economically justifiable way. The empirical data was collected through observations, time studies and interviews. The data was analysed based on the total truck cycle time, idle time and waiting time. The findings highlighted that the lift trucks had low utilisation rate and that there was room for improvements. Through a sensitivity analysis, it was concluded that two trucks from PVT and one truck from Tage could be removed. Additionally, the utilisation rate of the remaining trucks can be increased by letting several production lines share the same truck. For the new suggested internal transport to function properly, the first recommendation is to ensure that the trucks have enough battery capacity, otherwise, truck availability will decrease, making the overall production inefficient. The second recommendation is to eliminate non-value-adding transport activities performed by the machine operators. This can be done by delegating such transport activities to other employees, such as truck drivers and coordinators. These recommendations help the case company to improve efficiencies in their internal transport. Furthermore, the findings highlight the need and possibility for transport efficiency improvements overall and how it can be approached. / Syftet med detta examensarbete är att analysera den interna transporten av ett fallföretag och utveckla ett nytt tillvägagångssätt för att öka utnyttjandegraden av deras truckar. Fallstudien genomfördes vid ett stort tillverkningsföretag i södra Sverige och begränsad till två av deras produktionsverkstäder, betecknade PVT och Tage, med totalt 27 truckar. De aktuella uppgifterna som samlats in på fallföretaget medförde begränsningar på beslutsfattande, eftersom de endast angav det totala antalet timmar varje truck användes under ett år. Genom att kartlägga nuvarande materialhanteringsprocesser vid båda verkstäderna identifierades möjligheter i hur den interna transporten kan organiseras på ett ekonomiskt försvarbart sätt. Empirin samlades in genom observationer, tidsstudier och intervjuer. Data analyserades sedan utifrån truckarnas totala cykeltid, tid för stillastående samt väntetid. Baserat på observationerna och tidsstudierna identifierades truckar som hade låg utnyttjandegrad och således förbättringspotential. Resultatet från känslighetsanalys visade att två truckar från PVT och en truck från Tage kunde elimineras. Utnyttjandegraden på de återstående truckar kan då ökas genom att låta flera produktionslinjer dela på samma truck. För att den nya organisationen av den interna transporten ska fungera korrekt, rekommenderas att alla truckar har tillräcklig batterikapacitet, annars kommer trucktillgängligheten att minskas vilket skulle göra den totala produktionen ineffektiv. Den andra rekommendationen är att eliminera icke värdeskapande transportaktiviteter som utförs av maskinoperatörerna. Detta kan göras genom att delegera sådana transportaktiviteter till andra anställda, såsom truckförare och samordnare. Dessa rekommendationer hjälper fallföretaget att förbättra effektiviteten i sina interna transporter. Vidare visar studien behovet och möjligheten att driva effektivitetsförbättringar samt hur man kan gå till väga för att genomföra det.
194

Heavy Object Lifting Platform to Correct Human Balance and Posture

Raymundo, F., Quispe, G., Raymundo-Ibañeez, C. 25 November 2019 (has links)
This research document on technological development is aimed at workers in small companies, those that are developing well and soon to emerge as companies that will be positioned at the top of their labor sector. Starting from the problem at present with respect to the bad manipulation of loads it is arranged to solve the problem with established objectives to try to correct the corporal posture at the time of lifting an object with a machine that replaces the functions of the worker. The design and the solution was made based on the requirements of the worker, workers who have the need to load objects at a certain height, here the man-machine relationship, demands and desires that help to achieve the general objective are analyzed. In addition, it has the main function of this machine: To lift heavy objects of up to 150 kg of mass, this due to the implementation of a hydraulic piston in the lifting platform. The appropriate solution is an adaptation of a platform in the form of a truck forming an angle of 47.17 between the structure of the truck and the horizontal surface, this position is the most adequate so that the back does not suffer injuries during the handling of loads at work. The results give assurance that it is a machine of reliability and easy handling since it only requires an operator to control the objects and a flat position on the back without damaging the spine.
195

Propuesta de modelo de negocio de un food truck de venta de desayunos en una universidad privada de Chiclayo, 2016

Aliaga Camacho, Rocío Antonia, Esteves Vasquez, Kris Joan January 2017 (has links)
El presente trabajo tiene como objetivo establecer un modelo de negocio para un food truck de desayunos en una universidad privada de Chiclayo. La metodología aplicada para la investigación es cualitativa – exploratoria, se fundamenta en un proceso inductivo (explorar, describir y luego generar perspectivas teóricas), es decir va de lo particular a lo general; esta metodología permite obtener información en base a entrevistas realizadas a la comunidad universitaria. La investigación busca conocer la aceptación del modelo de food truck de venta de desayuno, se basó en el modelo Lean Canvas, desarrollado en el libro Running Lean de Ash Maurya, nos da un enfoque de nueve (9) dimensiones para tener en cuenta y poder lograr un modelo de negocio de éxito. La propuesta de valor obtenida, consiste en vender productos saludables que les ayude a promover la calidad y bienestar de la salud de nuestros clientes, por ello se ofrecerán desayunos elaborados a base de frutas, cereales andinos y sándwich preparados al instante, ofrecidos en unos envases biodegradables, cumpliendo con los estándares de salubridad. Asimismo se tendrá variedad en los productos a ofrecer, para que el cliente pueda escoger y se brindará una atención rápida y personalizada con la finalidad de cumplir con uno de los aspectos que los clientes valoran.
196

Assessing the human barriers and impact of autonomous driving in transportation activities : A multiple case study.

Gresset, Constance, Morda, David January 2021 (has links)
Background: The transport industry is facing new challenges such as increased competition between the actors and an increasing shortage of truck drivers. Implementing new technologies such as autonomous driving can represent a solution for companies to increase their competitiveness and gains. However, implementing such an innovative solution leads to a certain resistance to change that has to be dealt with, as well as concerns about the current jobs within the industry. Purpose: The purpose of this thesis is to assess the resistance to change linked to implementing this technology within Logistics Service Providers, provide solutions to overcome this resistance, as well as assessing the impact on jobs. Method: An inductive multiple case study has been used to conduct this research. The data was gathered from 12 semi-structured interviews with experts related to the transport industry. Then, thematic data analysis has been used to provide insights. Conclusion: The results show that the resistance is characterized by barriers to the technology and the resistance from the people, that support and communication is the key factor for successful implementation and that the truck driving professions will evolve considerably.
197

Optimal Hotel load management in 48V Class-8 Mild Hybrid Trucks

Singh, Somendra Pratap January 2021 (has links)
No description available.
198

Hur kan Skånetrafiken utveckla deras Content marketing utifrån Volvo Trucks filmer?

Möllerberg, Josefine January 2019 (has links)
I dagens samhälle cirkulerar stora mängder av reklambudskap genom olika digitala kanaler, vilket ställer högre krav på företagen att producera innehåll som är relevant, av nytta och värdeskapande för mottagaren. Innehållet har alltså betydelsefull roll för att ens nå ut till mottagare, vilket har lett till att marknadsföringsstrategin content marketing har vuxit med stormsteg de senaste åren. Ett företag som har använt content marketing under många år och visat stor framgång inom det är Volvo Trucks, vilket är ett av studiens fallstudieobjekt. Skånetrafiken är en organisation som nyligen har implementerat content marketing strategin i sitt marknadsföringsarbete, vilket är studiens andra fallstudieobjekt. Syftet med studien är att uppnå en ökad förståelse kring hur Volvo Trucks och Skånetrafiken använder content marketing i sina reklamfilmer idag, för att sedan öka insikten i hur Skånetrafiken kan utveckla sina reklamfilmer utifrån Volvo Trucks.För att analysera Volvo Trucks och Skånetrafikens reklamfilmer har fem näranalyser genomförts; tre av Volvo Trucks och två av Skånetrafiken. Därefter har en visuell low-fidelity- prototyp tagits fram för att påvisa hur Skånetrafiken skulle kunna utveckla sina reklamfilmer enligt Volvo Trucks användning av content marketing. Studiens resultat visade på att genom en utveckling av det underliggande budskapet och en ökning av igenkänningsfaktorn kan detta främja den känslomässiga reaktionen hos mottagaren och på så vis kommunicera det underhållande värdet. Prototypen visualiserar ett vardagligt händelseförlopp som består av ett barn som huvudkaraktär, en familjär miljö och ett tydligare underliggande budskap för att förmedla både det informativa och underhållande värdet. / In today's society, large volumes of advertising messages are circulated through different digital channels, which places higher demands on companies to create relevant, useful and value content for the customer. The content has a significant role in reaching out to the customers, which has led to the increasing growth of the strategy Content marketing (shortened CM in the paper) in the last few years. One company that has used CM for many years and proved successful in this is Volvo Trucks, which is one of the case study objects in this paper. Skånetrafiken is an organization that has recently implemented CM in its marketing work, which also is the papers case study object. The purpose of the study is to gain an increased understanding of how Volvo Trucks and Skånetrafiken use content marketing in their commercials, and then to gain insight into how Skånetrafiken can develop their commercials based on Volvo Trucks.To investigate which values Volvo Trucks is communicating and how Skånetrafiken can develop and improve its use of CM, five visual content analysis using Nordströms (1989) method called Näranalys, has been implemented; three of Volvo Trucks and two of Skånetrafiken. Subsequently, a visual low-fidelity prototype has been developed that shows how Skånetrafiken could develop its campaign film "Door closing" according to Volvo Trucks use of CM. The study's results showed that through the development of the underlying message and an increase in the recognition factor, this can promote the emotional response of the customer. The prototype visualizes an everyday storyline that consists of a child as the main character, a familiar environment and a clearer underlying message to communicate both the informative and entertaining value.
199

Fatigue Failure Model for Local Roads in Ohio that Use Road User Maintenance Agreements Due to the Increase in Truck Traffic

Gopallawa, Praveen January 2019 (has links)
No description available.
200

The Safety Impact of Raising Trucks' Speed Limit on Rural Freeways in Ohio

Ouedraogo, Nayabtigungu Hendrix January 2019 (has links)
No description available.

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