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Gravel roads form a significant share of the global road network, usually in sparsely populated rural areas. They are important, especially in agriculture, tourism, and forestry, connecting rural to urban areas. This systematic literature study comprises 105 reviewed publications on gravel road maintenance. Review articles on maintenance management practices, especially concerning objective condition assessment and data-driven methods (DDMs), are lacking. Therefore, this review provides a concise overview of current gravel road maintenance practices and ongoing research on objective condition assessment and DDMs for gravel road maintenance. It offers researchers in gravel road maintenance and other related fields a clear indication of where to focus their research efforts, as it suggests the direction for future research. Visual assessment methods are predominant for monitoring the condition of gravel roads, while objective methods and DDMs are not common. Research on gravel roads and their maintenance has increased in the last two decades, especially in North America and Northern Europe. Condition assessment is shifting from subjective to objective methods, utilizing knowledge from technological advancements in image processing, vibration and acoustics analysis, and so forth. There are some excellent research initiatives for objectively assessing the condition of gravel roads and DDMs, but the practical implementation is limited. Implementing objective assessment methods and DDMs generally improves the management of gravel roads with regard to decision-making, maintenance costs, safety, and the stability and comfort of the ride. Objective condition assessment and DMs have the potential to enhance maintenance practices in the maintenance of gravel roads., Sustainable maintenance of gravel road (HUG)

There is an increasing need for an effective monitoring strategy for the performance and condition of Down The Hole drilling. To achieve that, it is important to gain knowledge in the physics involved in Down The Hole drilling processes.A logical way to gain such understanding is to develop simulation models that are capable to represent the process. That requires physical understanding and thus, it is an iterative process. To capture the physics, it is essential to couple the axial impact, and the subsequent axial motion, with the rotation of the drill. The indentation into the rock due to impact and the subsequent resistance against rotation will couple the rotation to the axial motion and vice versa. The scenario is complicated due to the non-linear nature in the contacts and the varying stiffness of the rock.This paper presents a methodology that can be used to couple the axial and rotational motions of the DTH drills and explores the pros and cons of such a 3D simulation model.Keywords: DTH, 3D simulation, Condition monitoring

Needs for new competences and knowledge arise as industry 4.0 evolves in increasingly digitalized production. This development entails that job transformations and future skills need attention from the perspective of industry 5.0, where human and machine find ways of working together to improve production performance. Facing this perspective, one challenge is a growing need for novel lifelong learning initiatives, to meet emerging and altering occupations for the fulfilment of future skill requirements. This challenge is addressed here by portraying a case where three Swedish universities have formed a distinctive collaboration to develop a flexible (i.e. blended) course for professionals, in the subject of Digitally-enabled production. The purpose is to develop a sustainable collaboration between the universities and create a course format on master level addressing lifelong learning for the increasingly digitalized production. The ambition is to increase the impact of the universities respective efforts by sharing resources and utilizing individual specialized expertise to develop a practical and relevant course that can reach a larger target group. The course encompasses industry 4.0 readiness on three levels of production systems; plant-, production cell-, and component level; to adopt a holistic view of digitalization in production. We followed an action research approach for continuously collecting and documenting our experiences during the course development, implementation, and dissemination of the course. Within the frame of action research, an explorative case study describes and analyzes the initiative. The results highlight challenges and opportunities for succeeding with this form of co-produced course. The joint course gives professionals possibilities to work on cases from their own companies with expert supervision from three manufacturing levels to address complex challenges in industry 4.0 implementation. To conclude, the importance of li

Reliable simulations of the DTH drilling cycle are important in understanding the physics related todrilling, which in turn enables development of robust performance and condition monitoring methodologies. The DTH models available today model different aspects of the system like impact, hydraulics etc. separately. There are models available that incorporates hydraulics/pneumatics with onedimensional structural dynamics of the system. A common drawback of such models is that the effectof rotation is neglected. In reality rotation is an integral part of the DTH system and is interconnectedwith other parameters of drilling. This paper focuses on a simple model that combines rotation of thedrill string with the impact and hydraulic mechanics. The aim is to build upon this basic model tofacilitate the development of a more robust and accurate model that represents the condition andperformance monitoring problem.

The gravel road network is an essential function for rural residents and entrepreneurs. Traditional maintenance of gravel roads is well-functioning but provides a relatively high maintenance cost per unit length of the road. In addition, every maintenance action and extraction and transport of new gravel contribute to increased climate impact and resource depletion. Today, maintenance planning is carried out periodically based on the maintenance history, which also is reflected in the economic models and procurement methods. Current maintenance plans may be enhanced and will not be a reliable basis in the future, for instance due to climate change. Instead, real needs and conditions must be given greater consideration. Today, appropriate maintenance management systems are lacking, e.g., to be able to evaluate maintenance deficiencies, prioritize objects and choose the appropriate maintenance action. Moreover, the knowledge available at specific stakeholders is not shared with other actors. In this paper, an Information and Communication Technology (ICT) system for gravel road maintenance is proposed in the form of a cloud-based system covering the information needs of stakeholders in the gravel road maintenance ecosystem. Requirement specifications are given for the subsystems intended for the maintenance executioner and the maintenance planner. The specifications are based on workshops and interviews conducted with stakeholders, where requirements were acquired using techniques such as User stories, Use case scenarios, and mock-up prototypes. System examples corresponding to the requirements specifications are also given., Sustainable maintenance of gravel roads

High quality information is essential for the efficient decision making. Road condition is, together with traffic frequency, commonly used as input forclassifying road status. Road condition is also a major input for the maintenance executor (vehicle operator) when deciding on maintenance actions, such asamount of gravel to replenish. With better condition related information, the maintenance execution as well as maintenance planning could be greatlyimproved. The current deficiencies in gravel road condition monitoring methods and technologies are described in this paper, and an approach for objectivemeasurement of gravel road condition is proposed, including new measurement techniques and systems as well as information processing for decision making.This is realized by utilizing research findings from the area of signal processing, maintenance engineering, and information systems engineering in the specificcontext of gravel road monitoring, thus utilizing available technologies and methods as well as physics.

KIT, XPRES

As more features are added to the heavy duty construction equipment, its complexity increases and early fault detection of certain components becomes more challenging due to too many fault codes generated when a failure occurs. Hence, there is a need to complement the present onboard diagnostics method with a more reliable diagnostics method for adequate condition monitoring of the heavy duty construction equipment in order to improve uptime.Major components of the driveline (such as the gearbox, torque converter, bearings and axles) are components necessary to monitor. A failure among any of these major components of the driveline may result in the machine standing still until a repair is scheduled. In this paper, vibration based condition monitoring methods are presented with the purpose to provide a diagnostic framework possible to implement onboard for monitoring of critical driveline parts in order to reduce service cost and improve uptime.For the development of this diagnostic framework, sensor data from the gearbox, torque converter, bearings and axles are considered. Further, the feature extraction of the data collected has been carried out using adequate signal processing methods, which includes: Adaptive Line Enhancer and Order Power Spectrum respectively. In addition, Bayesian learning was utilized for adaptive learning of the extracted features for deviation detection. Bayesian learning is a powerful prediction method as it combines the prior information with knowledge measured to make updates. The results indicate that the vibration properties of the gearbox, torque converter, bearings and axle are relevant for early fault detection of the driveline. Furthermore, vibration provides information about the internal features of these components for detecting deviations from normal behavior. In this way, the developed methods may be implemented onboard for the continuous monitoring of these critical driveline parts of the heavy duty construction equipment. T

At excavations of quarries, construction sites or in mining, etc. articulated haulers are commonly used for the transportation of material. Thus, articulated haulers are exposed to a diversity of different worksites that all will load them differently. With a continuously growing market and added exhaust emission regulations, the machines need to be continuously optimized to meet durability and weight (fuel efficiency) requirements. In the structural design of any given component in an articulated hauler, the assumed loads used will reflect on its design. However, it is rarely the case that the loads used in the design procedure strictly represents the dynamic loads a hauler will be subjected to. As a result, the machines are generally oversized. To address the issue of oversized components, a statistical approach for the estimation of their fatigue life may be utilized. With the aid of power spectral density estimates of a components dynamic loads in combination with a finite element model of the component its vibration response in terms of power spectral densities may be estimated. Based on the vibration response spectra the component's fatigue life may be estimated assuming that the components dynamic loads may be considered as weakly stationary stochastic processes. To investigate if the dynamic loads used for fatigue life estimation may be considered as weakly stationary stochastic processes; stationarity tests have been carried out as well as estimates of the kurtosis and the mean square value as a function of time have been produced. The results indicate that the dynamic loads may not be considered as weakly stationary stochastic processes. Furthermore, by segmenting the dynamic load time series into segments that can be considered as weakly stationary the estimated fatigue life seems to decrease slightly if compared to the case when assuming that the dynamic loads are weakly stationary.

Light road construction machinery such as manually operated reversible plate compactors or reversible vibratory plates are used for compacting sand, gravel, rock fill, soil, etc. with the aid of vibration. The purpose of the vibration excitation of the ground is to produce pressure waves that penetrate the ground layers to overcome the resisting friction between the soil particles, in order to reduce the soil porosity and permeability. During compaction, the ground is dynamically excited via a compactor's bottom plate. However, the actual spatial dynamic behaviour of a compactor's bottom plate during operation may not be known. To increase the knowledge concerning the spatial dynamic behaviour of a compactor's bottom plate during operation, a reversible plate compactor whose bottom plate has been considered as a rigid body in its design has been investigated. An increased knowledge concerning the dynamic behaviour of compactor's bottom plate during operation is likely to enable a further improvement in the design of reversible vibratory plates concerning their performance, vibration exposure of operator, etc. To acquire knowledge concerning the dynamic behaviour of the bottom plate of a reversible vibratory plate during operation, spatial measurements of its acceleration response have been carried out on it during operation on rubber mats. Operating deflection shape analyses of the bottom plate have been carried out based on both power spectral density estimates and power spectrum estimates of the recorded acceleration responses. The fact that the frequency of the vibration excitation of the reversible plate compactor varied slightly, and thus induced a frequency modulated vibration response of the plate, was considered in the ODS analysis. The analyses indicate different dynamic behaviours of the bottom plate depending on the operation of the reversible vibratory plate, i.e. if it operates in idle, reverse or forward motion.

New competences and knowledge needs arises as manufacturing industry evolves and becomes increasingly digitalized. Facing this transformation, one of the challenges is the continuous and growing need for novel initiatives for competence development.The case portrayed here stems from a Swedish cross-university project aiming to jointly develop and offer courses for competence development of professionals in the manufacturing and IT sectors. The ambition is to increase the impact of the universities' respective efforts of meeting industry competence needs, where the continuous digital transformation entails that employees must develop or even change their qualifications. The case outlined focus co-production of a joint course package, at master level, between three universities and their respective company networks. Participating universities have long traditions in working closely with companies in research and education, where approaches for co-production have evolved over time. We make use of our joint understanding of the manufacturing industry's specific competence needs and our experiences of sustainable course formats for participants working full time.The joint course covers aspects of a manufacturing company on three levels: plant level i.e. material and production flows, cell level e.g. robotic simulation and visualisation, and system level i.e. data acquisition and monitoring through sensors. Each university is developing a course module of 2.5 ECTS, addressing a level respectively of their specialist competence. Participants are to complete assignments for each course module, i.e. for all three manufacturing levels, where the previous assignment provides an input to the next level, enabling the participants to encompass a holistic view of a manufacturing system. Participants need to combine study and work and at the same time they wish to extend their network, hence we are adopting a blended learning approach, where virtual labs and web conferences are mix

In order to reduce unnecessary stops and expensive downtime originating from clutch failure of construction equipment machines; adequate real time sensor data measured on the machinein combination with feature extraction and classification methods may be utilized. This paper, based on a study at Volvo Construction Equipment,presents a framework with feature extraction methods and an anomaly detection module combined with Case-Based Reasoning (CBR) for on-board clutch slippage detection and diagnosis in a heavy duty equipment. The feature extraction methods used are Moving Average Square Value Filtering (MASVF) and a measure of the fourth order statistical properties of the signals implemented as continuous queries over data streams. The anomaly detection module has two components,the Gaussian Mixture Model (GMM) and the Logistics Regression classifier. CBR is a learning approach that classifies faults by creating a new solution for a new fault case from the solution of the previous fault cases. Through use of a data stream management system and continuous queries (CQs), the anomaly detection module continuously waits for a clutch slippage event detected by the feature extraction methods, the query returns a set of features which activates the anomaly detection module. The first component of the anomaly detection module trains a GMM to extracted features while the second component uses a Logistic Regression classifier for classifying normal and anomalous data. When an anomalyis detected, the Case-Based diagnosis module is activated for fault severity estimation., Validerad;2018;Nivå 1;2018-03-19 (rokbeg)

The drilling industry is steadily moving towards automation. To have a better control over the drilling operation and to optimize the drilling performance, it is necessary to have a good understanding of the physics involved in the process. A good simulation model of the drilling process/system would be of great value in assisting this and in enabling the development of strategies to optimize it. A representative simulation model can provide insights into various phenomena that appear during drilling for different drilling conditions. Such a model is also likely to be of assistance in preparing various measurements. Issues such as choosing the type of sensors, their positions and which quantities to measure are supported by a model. A well calibrated model in combination with information extracted from measured data are hence likely to assist in selecting control strategies for optimized drilling performance. In this paper we present a MATLAB based 1D simulation model of a Down The Hole (DTH) drill and compare it with an existing 1D model in terms of computational speed and accuracy. The emphasis is to make a 3D model of a DTH system that is computationally efficient and accurate.

Quantifying and Monitoring of drilling performance are becoming exceedingly important in the case of Down the Hole drilling. Various economic, environmental and safety constraints are driving the drilling process to become more efficient. To make a robust system that would enable the performance/condition monitoring of the drilling, we must understand how different properties like different line pressure etc. respond to various drilling conditions and what information can they provide regarding the Drilling Performance. A comparison of different properties like spectral properties, of the vibration signals and Pressure signals under known conditions would enable better understanding of the drilling system and the physics behind the process. A comparison is made between the Spectral properties of the vibrational signals obtained from remote locations on the drill rig and pressure signals that provide the feed and holdback forces to the drill string and a correlation between their characteristics and patterns under good and bad drilling conditions have been made. A simplified model of the system is simulated and results are compared with the patterns obtained from analyzing the Vibration signals., Ej belagd 170403

Mellan bebyggda enklaver och väldefinierade stadslandskap stöter man på underliga ytor, till synes tomma, ödsliga och utan någon som helst funktion. Ytorna definieras ofta som stadens mellanrum och det är utifrån dessa platsers existens som uppsatsen grundas på. Mellanrummen skiljer sig ofta markant från den välordnade och kontrollerade staden, men är alltjämt en del av den. Målet är att genom litteraturstudier undersöka vad mellanrummens värden tros ha för staden och dess invånare. Studien ska utgöra ett underlag till en fortsatt diskussion kring vad som betecknar dessa platser och vad de kan ha för värde utifrån ett planerings- och användarperspektiv. Genom litteraturstudien har jag kommit fram till att det är mellanrummens oklara, odefinierade och flyktiga karaktär som är dess största tillgång och värde, och att mellanrummet inte innehåller några förutbestämda regler för hur man som brukare av landskapet bör bete sig. Stadens mellanrum är öppna för appropriering, självorganisering, kreativitet och spontanitet. Mellanrummen är en plats där användare kan agera tillfälligt i nuet. Detta innebär att mellanrummen utgör ett alternativ till det kontrollerade offentliga rummet, och kan på så vis kan bli en frizon för det som annars inte passar in. Uppsatsen behandlar även arkitekten och planerarens förhållningssätt till staden och dess mellanrum. Jag har genom studien kunnat se tre olika riktlinjer som skiljer sig åt. Den första riktlinjen menar att; bara genom att lämna mellanrummen åt sitt blivande kan de överleva och utvecklas. Den andra faller tillbaka på ett traditionellt planeringsideal och ser inte dessa platser som en del av professionen. Den tredje riktlinjen utgör ett förhållningssätt som utgår från att staden alltid är i förändring. Det är ett synsätt där den lokala platsen och dess historia spelar stor roll för hur platsen utvecklas. Riktlinjen menar att genom en växelverkande process kan arkitekturen kopplas ihop mer sammanflätat med staden och dess invånare, Between built enclaves and well-defined urban landscapes, peculiar areas emerges, seemingly empty, desolate, and without any function. These residual places are the subject of that the thesis is based upon. Residual space often differs significantly from the well-ordered and controlled urban areas, but is nevertheless a part of it. The goal is to, through literature studies, explore the values of residual spaces could have for urban inhabitants and for the city itself. The study will provide a basis to conduct a discussion around what these sites represent from a user- and planning perspective. Thanks to the literature study, I have come to the conclusion that it is the vague, undefined and volatile character of the residual space that is it’s greatest asset and value. The residual space contains no predetermined rules or demands of certain behaviour. Residual space is open to appropriation, self-organization, creativity and spontaneity, where users are able to act temporarily in the present. This means that the residual space is an alternative, and thus can become a free zone for what does not fit into the controlled public space. The thesis also deals with the architects and planners different approaches to the city and it’s spaces. Thanks to the study I was able to see three different guidelines that differs. The first guideline says that, only by leaving residual space from intervention, they can survive and evolve. Others fall back on traditional planning ideals and doesn’t see these places as part of their profession. The third way of approaching residual space and town planning assumes that the city is always changing. The local site and it’s history plays a big part in how the site developes. Through this interactive process architecture can be more closely connected with the city and its inhabitants.

In Atlas Copco a wide range of machines is produced from surface drill rigs, exploration drill rigs, underground drill rigs both for mining and construction to underground loader and haulers for mines. Recently new rock excavation methods have developed in cooperation with large mining companies. The machines are produced in low volume and often customized although having a modular approach. Time for validation is limited due to machines available for test are planned for customer delivery. It is on regular basis needed to validate and investigate vibrational behavior of installations as power packs and drivelines to get loads for simulation, identify resonances, operational deflection shapes, and vibration and stress levels for life length estimations under operational conditions. The time for a 40-180 Channel measurement is now down the range of 13 days. To reduce the time it takes to perform measurement a systematic approach has been taken that includes mainly three areas. First the Bookkeeping of all information and data needed for the analysis and reporting is input before or during the measurement. Systematic Approach of how to setup sensors, handle cable and equipment, planning and measurement. This includes practical examples of how to. Finally it is very important to take steps to assure Quality early in the measurement and also avoiding disturbances in the sensor path. There will be practical examples of important disturbances to look out for and quality check to perform. It should also be noted that the measurements is regular measured in mines or start up halls under rpm sweeps or/and operating conditions of the machines.

Quantifying and Monitoring of drilling performance are becoming exceedingly important in the case of Down the Hole drilling. Various economic, environmental and safety constraints are driving the drilling process to become more efficient. To make a robust system that would enable the performance/condition monitoring of the drilling, we must understand how different properties like different line pressure etc. respond to various drilling conditions and what information can they provide regarding the Drilling Performance. A comparison of different properties like spectral properties, of the vibration signals and Pressure signals under known conditions would enable better understanding of the drilling system and the physics behind the process. A comparison is made between the Spectral properties of the vibrational signals obtained from remote locations on the drill rig and pressure signals that provide the feed and holdback forces to the drill string and a correlation between their characteristics and patterns under good and bad drilling conditions have been made. A simplified model of the system is simulated and results are compared with the patterns obtained from analyzing the Vibration signals.

In In this demo session, it will be shown how to perform Active Noise Control (ANC) and various important Acoustic experiments remotely on the remotely controlled ANC laboratory developed by Blekinge Institute of Technology, Sweden. An important consideration in ANC is the active control’s performance dependence on the spatial position of the reference and error sensors, etc. This will be highlighted particularly. This feature is recently implemented using stepper motors which can be controlled via the Internet. It will be demonstrated how to write and upload active noise control algorithms e.g. Filtered-X Least Mean Square (FXLMS) to a digital signal processors (DSP) board. For the acoustic experiments various interesting acoustic properties such as waveforms, speed of sound, mode shapes and sound pressure spectra may be measured. A short guide about the measurements and PowerPoint presentation will be provided during the demo to facilitate for the users. The Lab setup and the equipment will be shown to the user using Skype and a web camera., Conference of 13th International Conference on Remote Engineering and Virtual Instrumentation, REV 2016 ; Conference Date: 24 February 2016 Through 26 February 2016; Conference Code:121080

This paper describes a remote implementation of Galileos inclined plane experiment, focused on secondary school students. A remotely controlled inclined plane has been designed and implemented in the VISIR lab at Blekinge Institute of Technology (BTH), Sweden. In this demo session, it will be demonstrated how to perform measurements remotely in the remotely controlled Inclined Plane Laboratory. A web camera is used to show the experiment. Data concerning the distance a cube has slided down the inclined plane are collected. These data are stored in a file and can subsequently be analyzed by the students. The friction acting on the cube sliding down the inclined plane and its acceleration may for instance be investigated., Conference of 13th International Conference on Remote Engineering and Virtual Instrumentation, REV 2016 ; Conference Date: 24 February 2016 Through 26 February 2016; Conference Code:121080

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Ej belagd 170403

The learning outcomes or educational objectives (goals) of a remote controlled laboratory via the Internet is the subject of discussion in this paper. The developers of remote laboratories are often self motivated individuals or academic groups, who only focus on development, accessibility and usability of their laboratories. The key question i.e. the intended learning outcomes or educational goals of a remotely controlled laboratory are frequently ignored or simply not given enough priority to be considered. This may lead to under utilization or complete failure of a particular remote laboratory. In this paper the challenges in formulating and achieving the educational objectives of a remotely controlled active noise control and acoustics laboratory are discussed.