The primary function of an automobile rear View Mirror is to provide the driver with a clear vision interpretation of all objects to the rear and side of the vehicle. The rear View Mirror is a bluff body and there are several problems associated with the rear View Mirror. These include buffeting, image distortion (due to aerodynamically induced and structural vibration), aerodynamically induced noise (due to cavities and gaps) and water and dirt accumulation on Mirror glass Surface. Due to excessive glass vibration, the rear View Mirror may not provide a clear image. Thus, vibrations of Mirror can severely impair the driver's vision and safety of the vehicle and its occupants. The rear View Mirrors are generally located close to the A-pillar region on the side window. A conical vortex forms on the side window close to A-pillar due to A-pillar geometry and the presence of side rear View Mirror and flow separation from it makes the airflow even more complex. The primary objective of this work is to study the aerodynamic pressures on Mirror Surface at Various speeds to determine the effects of aerodynamics on to Mirror vibration. Additionally, the Mirror was modified by Shrouding around the external periphery to determine the possibility of minimisation of aerodynamic pressure fluctuations and thereby vibration. The Shrouding length used for the analysis was of 24mm, 34mm and 44mm length. The mean and fluctuating pressures were measured using a production rear side View Mirror fitted to a ¼ quarter production passenger car in RMIT Industrial Wind Tunnel. The tests were also conducted in semi-isolation condition to understand influence of the A-pillar geometry. The mean and fluctuating pressures were converted into non-dimensional pressure coefficients (Cp and Cprms) and the frequency content of the fluctuating pressure was analysed. The results show that the fluctuating aerodynamic pressures are not uniformly distributed over an automobile Mirror Surface. The highest magnitude of fluctuating pressure for the standard Mirror was found at the central bottom part of the Mirror Surface. The highest magnitude of fluctuating pressure for the modified Mirror was found at the central top part of the Mirror Surface. As expected, the modification has significant effect on the magnitude of fluctuating pressure. The results show that an increase of Shrouding length reduces the magnitude of the fluctuating pressure. The frequency-based analysis was done to understand the energy characteristics of the flow, particularly to its phase, since it is the out of phase components that usually cause Mirror rotational vibration. The spectral analysis showed that the magnitude of the energy distribution reduces with increase of shrouding length throughout the frequency range. Flow visualisation was also used to supplement the pressure data. The effects of yaw angles were not included in this study, however, are thought to be worthy of further investigation. On road testing and the variation of mirror locations might have some effects on the fluctuating pressures. These need to be investigated in the future work. The quarter model used in this study was a car specific. However, for more generic results, a simplified model with variable geometry can be used in future study.

The purpose of the present study was to examine effects of driver, vehicle, and environment characteristics on Collision Warning System (CWS) design. One hypothesis was made that the capability of collision avoidance would not be same among a driver, vehicle, and environment group with different characteristics. Accident analysis and quantitative analysis was used to examine this hypothesis in terms of ‘risk’ and ‘safety margin’ respectively. Rear-end collision had a stronger focus in the present study. As a result of accident analysis, heavy truck showed a higher susceptibility of the fatal rear-end accidents than car and light truck. Also, dry road surface compared to wet or snow, dark condition compared to daylight condition, straight road compared to curved road, level road compared to grade, crest or sag, roadway having more than 5 travel lanes compared to roadway having 2, 3 or 4 travel lanes showed a higher susceptibility of the fatal rear-end accidents. Relative rear-end accidents involvement proportion compared to the other types of collision was used as a measure of susceptibility. As a result of quantitative analysis, a significant difference in terms of Required Minimum Warning Distance (RMWD) was made among a different vehicle type and braking system group. However, relatively small difference was made among a different age, gender group in terms of RMWD. Based on the result, breaking performance of vehicle should be regarded as an input variable in the design of CWS, specifically warning timing criteria, was concluded.

Examensarbetet har genomförts i samarbete med Meritor HVS AB i Lindesberg som tillverkar fram- och bakhjulsaxlar till buss- och lastbilsindustrin. Projektet behandlar de fixturer som används vid transport av bakhjulsaxlar. Målet med arbetet var att utveckla en ny transportfixtur som passar majoriteten av deras bakaxelmodeller och som förebygger skador vid transport. Projektet har genomförts enligt metodiken systematisk konstruktion som beskrivs enligt Johannesson, Persson och Petterssons (2004). Systematisk konstruktion kan delas in i fem steg: produktspecificering, konceptgenerering, utvärdering och val av koncept, detaljkonstruktion samt slutkonstruktion. De problem som Meritor har med transportfixturerna är att de i hög grad slits och att skyddsbeläggningarna inte håller. Det finns för projektet 30 aktuella bakaxelmodeller som skall kunna transporteras med samma fixtur. Meritor använder sig av en grundfixtur och diverse nödlösningar för att kunna hantera alla modeller. De nya fixturkoncepten begränsas av de nuvarande stålrackens dimensioner och fixturernas positioner i dem. Utifrån de konceptförslag som tagits fram i arbetet, fördes de två mest lämpade koncepten vidare till slutkonstruktion. Det första konceptet, T-fixturen, bygger på den fixtur som används idag och är således ett förbättringsförslag. Förbättringarna består av en ökad anläggningsyta, bättre skyddsbeläggning samt vikt- och hållfasthetsoptimeringar. Det andra konceptet, pinnfixturen, bygger även den på samma grundfixtur men använder sig av två öglor som finns på varje axelmodell. Genom att placera axelns öglor över två pinnar i fixturen uppnås en total fixering av axeln. / This thesis has been carried out in cooperation with Meritor HVS AB in Lindesberg that manufactures front and rear wheel axles for the bus and truck industry. The project focuses on fixtures used in the transportation of rear wheel axles. The goal of the project was to develop a new transport fixture that suits the majority of rear axle models and prevents damage during transport. The project is based on the systematic design methodology described by Johannesson, Persson and Pettersson (2004). Systematic design can be divided into five stages: product specification, concept generation, concept evaluation and selection, detailed design and final design. The main issue with Meritors fixtures is that they wear out easily and that the protective coating breaks. One fixture type needs to be able to handle the 30 rear axle models relevant to this project. Meritor currently uses a basic structure combined with miscellaneous temporary solutions to handle all models. The new conceptual fixture is limited by the current steel rack, it´s dimensions and fixture positions within the construction. Based on the concept designs put forward in the work, the two most suitable concepts were brought through to final design. The first concept, the T-fixture, was based on the fixture in use today and is thus an improvement. The improvement consists of an increased contact surface, better protective coating as well as weight and strength optimizations. Concept two, the Rod fixture, is also based on the same basic fixture but uses two loops that are available on every axle model. By placing the axle loops over the two rods in the fixture, a total immobilization of the axle is achieved.

<p>The purpose of the present study was to examine effects of driver, vehicle, and environment characteristics on Collision Warning System (CWS) design. One hypothesis was made that the capability of collision avoidance would not be same among a driver, vehicle, and environment group with different characteristics. Accident analysis and quantitative analysis was used to examine this hypothesis in terms of ‘risk’ and ‘safety margin’ respectively. Rear-end collision had a stronger focus in the present study. </p><p>As a result of accident analysis, heavy truck showed a higher susceptibility of the fatal rear-end accidents than car and light truck. Also, dry road surface compared to wet or snow, dark condition compared to daylight condition, straight road compared to curved road, level road compared to grade, crest or sag, roadway having more than 5 travel lanes compared to roadway having 2, 3 or 4 travel lanes showed a higher susceptibility of the fatal rear-end accidents. Relative rear-end accidents involvement proportion compared to the other types of collision was used as a measure of susceptibility. </p><p>As a result of quantitative analysis, a significant difference in terms of Required Minimum Warning Distance (RMWD) was made among a different vehicle type and braking system group. However, relatively small difference was made among a different age, gender group in terms of RMWD. Based on the result, breaking performance of vehicle should be regarded as an input variable in the design of CWS, specifically warning timing criteria, was concluded.</p>

During monitoring of rear-mounted equipment, frequent rearward turning of tractor drivers in awkward postures can cause musculoskeletal disorders related to the back, neck, and shoulders. A camera-based monitoring system, consisting of one or more cameras placed on the implement and a monitor placed inside the tractor cab, has potential ergonomic benefits compared with traditional implement monitoring strategies by reducing the rearward turning and twisting movements of tractor drivers. A camera-based monitoring system was compared with two traditional monitoring strategies (direct looking and using rear-view mirrors) in a lab environment using a Tractor Air-Seeder Driving Simulator. The operator’s reaction time and response errors, head/neck movement (acceleration), and neck muscle temperature were compared for the three monitoring strategies. The camera-based monitoring system yielded significantly (α=0.05) better outcomes in terms of acceleration and muscle temperature values. No significant difference was observed for response errors.

During monitoring of rear-mounted equipment, frequent rearward turning of tractor drivers in awkward postures can cause musculoskeletal disorders related to the back, neck, and shoulders. A camera-based monitoring system, consisting of one or more cameras placed on the implement and a monitor placed inside the tractor cab, has potential ergonomic benefits compared with traditional implement monitoring strategies by reducing the rearward turning and twisting movements of tractor drivers. A camera-based monitoring system was compared with two traditional monitoring strategies (direct looking and using rear-view mirrors) in a lab environment using a Tractor Air-Seeder Driving Simulator. The operator’s reaction time and response errors, head/neck movement (acceleration), and neck muscle temperature were compared for the three monitoring strategies. The camera-based monitoring system yielded significantly (α=0.05) better outcomes in terms of acceleration and muscle temperature values. No significant difference was observed for response errors.

This master‘s thesis deals with a design construction of a bath body and an opening rear face for a dedicated tractor trailer MEGA EASY. The purpose of this master’s thesis is to create research and concept of the bath body and the rear face, to design mechanism for opening the rear face and to compute the construction using the finite element method. Additionally, this master’s thesis includes selected technical drawings.

abstract: Toward the ambitious long-term goal of a fleet of cooperating Flexible Autonomous Machines operating in an uncertain Environment (FAME), this thesis addresses several critical modeling, design and control objectives for ground vehicles. One central objective was to show how off-the-shelf (low-cost) remote-control (RC) “toy” vehicles can be converted into intelligent multi-capability robotic-platforms for conducting FAME research. This is shown for two vehicle classes: (1) six differential-drive (DD) RC vehicles called Thunder Tumbler (DDTT) and (2) one rear-wheel drive (RWD) RC car called Ford F-150 (1:14 scale). Each DDTT-vehicle was augmented to provide a substantive suite of capabilities as summarized below (It should be noted, however, that only one DDTT-vehicle was augmented with an inertial measurement unit (IMU) and 2.4 GHz RC capability): (1) magnetic wheel-encoders/IMU for(dead-reckoning-based) inner-loop speed-control and outer-loop position-directional-control, (2) Arduino Uno microcontroller-board for encoder-based inner-loop speed-control and encoder-IMU-ultrasound-based outer-loop cruise-position-directional-separation-control, (3) Arduino motor-shield for inner-loop motor-speed-control, (4)Raspberry Pi II computer-board for demanding outer-loop vision-based cruise- position-directional-control, (5) Raspberry Pi 5MP camera for outer-loop cruise-position-directional-control (exploiting WiFi to send video back to laptop), (6) forward-pointing ultrasonic distance/rangefinder sensor for outer-loop separation-control, and (7) 2.4 GHz spread-spectrum RC capability to replace original 27/49 MHz RC. Each “enhanced”/ augmented DDTT-vehicle costs less than 􀀀175 but offers the capability of commercially available vehicles costing over 􀀀500. Both the Arduino and Raspberry are low-cost, well-supported (software wise) and easy-to-use. For the vehicle classes considered (i.e. DD, RWD), both kinematic and dynamical (planar xy) models are examined. Suitable nonlinear/linear-models are used to develop inner/outer-loopcontrol laws. All demonstrations presented involve enhanced DDTT-vehicles; one the F-150; one a quadrotor. The following summarizes key hardware demonstrations: (1) cruise-control along line, (2) position-control along line (3) position-control along curve (4) planar (xy) Cartesian stabilization, (5) cruise-control along jagged line/curve, (6) vehicle-target spacing-control, (7) multi-robot spacing-control along line/curve, (8) tracking slowly-moving remote-controlled quadrotor, (9) avoiding obstacle while moving toward target, (10) RC F-150 followed by DDTT-vehicle. Hardware data/video is compared with, and corroborated by, model-based simulations. In short, many capabilities that are critical for reaching the longer-term FAME goal are demonstrated. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2015

To perform lane-change maneuvers safely, sufficient distance to the subsequent traffic is required. In the present study distance estimations to the subsequent vehicle (Experiment 1) and lane-change decisions (Experiment 2) were gathered in dependency of left wing-mirror settings: Different vertical settings resulted in low and high vehicle positions with less or more pavement visible in the mirror. Additionally, the visibility or non-visibility of the observer's rear door was varied. Findings indicated that a low vertical position of the following vehicle in the mirror and a visible rear door lead to shorter distance estimations and more cautious lane-change decisions than a high vertical position and a non-visible rear door. Consequently, wing-mirror settings are important for traffic safety.

The current driving simulator study investigates the effect of 2 distinct levels of distraction on a drivers’ situational awareness and latent and inherent hazard anticipation. In this study, rear-end crashes were used as the primary crash configuration to target a specific category of crashes due to distraction. The two types of task load used in the experiment was a cognitive distraction (mock cell-phone task) & visual distraction (I-pad task). Forty-eight young participants aged 18-25 years navigated 8 scenarios each in a mixed subject design with task load (cognitive or visual distraction) as a between-subject variable and the presence/absence of distraction representing the within-subject variable. All participants drove 4 scenarios with a distraction and 4 scenarios without any distraction. Physiological variables in the form of Heart rate and heart rate variability was collected for each participant during the practice drives and after each of the 8 experimental drives. After the completion of each experimental drive, participants were asked to fill up a NASA TLX questionnaire which quantifies the overall task load experienced by giving it a score between 1 and 100, where higher scores translate to higher perceived task load. Eye-movements were also recorded for the proportion of latent and inherent hazards anticipated and mitigated for all participants. Standard vehicle data (velocity, acceleration & lane offset) were also collected from the simulator for each participants’ each drive. Analysis of data showed that there was a significant difference in velocity, lane offset and task load index scores across the 2 groups (between-subject factors). The vehicle data, heart rate data and TLX data was analyzed using Mixed subject ANOVA. There was also a logistic regression model devised which showed significant effects of velocity, lane offset, TLX scores and age on a participants’ hazard anticipation abilities. The findings have a major practical implication in reducing drivers’ risk of fatal, serious or near crashes.