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Self-calibration of sensors has become highly essential in the era of self-driving cars. Reducing the sensors’ errors increases the reliability of the decisions made by the autonomous systems. Various methods are currently under investigation but the traditional methods still prevail which maintain a strong dependency on human experts and expensive equipment that consume significant amounts of labor and time. Recently, various calibration techniques proposed for extrinsic calibration for Autonomous Vehicles (AVs) mostly rely on the camera 2D images and depth map to calibrate the 3D LiDAR points. While most methods work with the whole frame, some methods use the objects in the frame to perform the calibration. To the best of our knowledge, majority of these self-calibration methods rely on using actual or falsified ground truth values.

With the development of intelligent and electric vehicles, higher requirements are put forward for the active braking and regenerative braking ability of the braking system. The traditional braking system equipped with vacuum booster has difficulty meeting the demand, therefore it has gradually been replaced by the integrated braking system. In this paper, a novel Integrated Braking System (IBS) is presented, which mainly contains a pedal feel simulator, a permanent magnet synchronous motor (PMSM), a series of transmission mechanisms, and the hydraulic control unit. As an integrative system of mechanics-electronics-hydraulics, the IBS has complex nonlinear characteristics, which challenge the accurate pressure control. Furthermore, it is a completely decoupled braking system, the pedal force doesn’t participate in pressure-building, so it is necessary to precisely identify driver’s braking intention.

Lane detection is an important component in automatic pilot system and advanced driving assistance system (ADAS). The stability and precision of lane detection will directly determine precision of control and lane plan of vehicles. Traditional mechanical vision lane detection approaches in complicated environment have the deficiencies of low precision and feature semantic description disabilities. But the lane detection depending on deep learning, e.g. SCNN network, LaneNet network, ENet-SAD network have imbalance problems of splitting precision and storage usage. This paper proposes an approach of high-efficiency deep learning Segnet-LSTM semantic segmentation network. This network structure is composed with encoding network and corresponding decoding networks. First, convolution and maximum pooling. The proposal extracts texture details of five images and stores searching position of maximum pooling. Meanwhile, it will implement interpolate processing to the lost points.

Over the years, the complexity of autonomous vehicle development (and concurrently the verification and validation) has grown tremendously in terms of component-, subsystem- and system-level interactions between autonomy and the human users. Simulation-based testing holds significant promise in helping to identify both problematic interactions between component-, subsystem-, and system-levels as well as overcoming delays typically introduced by the default full-scale on-road testing. Software in Loop (SiL) simulation is utilized as an intermediate step towards software deployment for autonomous vehicles (AV) to make them reliable. SiL efforts can help reduce the resources required for successful deployment by helping to validate the software for millions of road miles. A key enabler for accelerating SiL processes is the ability to use Simulation as a Service (SaaS) rather than just isolated instances of software.

This paper studies the implementation and validation of control algorithms for an autonomous drag racing vehicle. The previously developed modeling equations are first implemented with control in a realistic simulation environment complete with synthetic sensor data and decision-making algorithms. The controller is then transformed into an embedded on-board processing unit for on-vehicle testing. Camera, lidar, and radar sensor data are investigated and algorithms are created to provide information from physical sensors rather than synthetic data. The control related to actuation of the steering, brake, throttle, and shifting systems are further discussed, along with human-vehicle interaction in terms of handoff and emergency takeovers. The control algorithms are then validated on the research vehicle. This is demonstrated by completing a fully autonomous quarter-mile drag race, complete with camera detection for the staging sequence and MPC trajectory following.

Driving cycles are usually defined by vehicle speed as a function of time and they are typically used to estimate fuel consumption and pollutant emissions. Currently, certification driving cycles are mainly used for this purpose. Since they are artificially generated, the resulting estimates and analyzes can generally be biased. In order to address these shortcomings, recent research efforts have been directed towards development of statistically representative synthetic driving cycles derived from recorded real-world data. To this end, this paper focuses on synthesis of multidimensional driving cycles using the Markov chain-based method and particularly on their validation. The synthesis is based on Markov chain of fourth order, where the road slope is accounted, as well. The corresponding transition probability matrix is implemented in the form of a sparse matrix parameterized with a rich set of recorded city bus driving cycles.

Multiple models to estimate motion sickness (MS) have been proposed in the literature; however, few capture the influence of visual cues, limiting the models’ ability to predict MS that closely matches experimental MS data. This is especially significant in the presence of conflicts between visual and vestibular sensory signals. This paper provides an analysis of the gaps within existing MS estimation models and addresses these gaps by proposing the visual-vestibular motion sickness (VVMS) model. In this paper, the structure of the VVMS model, associated model parameters, and mathematical and physiological justification for selecting these parameters are presented. The VVMS model integrates vestibular sensory dynamics, visual motion perception, and visual-vestibular cue conflict to determine the conflict between the sensed and true vertical orientation of the passenger.

Nd: YAG Laser Welding Process (LWP) is the most efficient method commonly used for the joining of different kinds of materials, whether it can be a sheet or plate. LWP in general, uses high power density, frequency and travel speed or feed rate as primary process parameters in order to perform a joining process across the metals. This paper investigates the effect of free vibrational characteristics for Stainless Steel 304 (SS 304) joints which are reinforced with Al2O3 micro particles processed by dual side (welding performed on the top and bottom surface of sheets) Nd: YAG LWP. The inclusion of micro particles was inserted directly across the weld pool region, by fabricating drills with a constant gap between each drilled holes. Totally 12 samples were fabricated with different laser power, travel speed and by keeping the frequency level as constant for all the experiments.

The power train components of vehicles are firmly attached to the Engine mounting bracket. It plays very important role in performance of vehicle and its comfortable ride. As SAE India Supra car was high performance vehicle, the mounting brackets undergo high static and dynamic loading conditions due to that Huge amount of vibrations were produced. By careful designing and analysis of engine mounting bracket we can mitigate the vibration produced in the vehicle. The current paper discusses the modelling of bracket in Catia, Static and Modal Analysis of bracket was carried out in FEAST Software. Optimization of bracket is carried out in hyper mesh Software for weight reduction. A Formula Student car is required to be highly manoeuvrable and quick with high rates of acceleration and deceleration. Hence the mounting of the engine should be well constrained and the mount brackets need to be light-weight and designed to safely bear the inertial loads and maximize vibration transmission.

The current work investigates the hot corrosion demeanour of Hastelloy X weldment produced with autogenous mode through key-hole plasma arc welding (K-PAW). The hot corrosion test has been performed for weldment in molten salt-1 (MS-1) (75 % Na2SO4 + 25 % V2O5) and molten salt-2 (MS-2) (75 % Na2SO4 + 20 % V2O5 + 5 % NaCl) circumstance for 25 hrs (25 cycles) at 900 °C. The MS-1 substrate of both base metal and weldment provided the lowest weight gain than the MS-2 substrate. The NaCl in the MS-2 causes severe hot corrosion on the substrate, whereas the absence of NaCl in MS-1 reduces the hot corrosion effects. The highest parabolic constant is observed for K-PAW weldment in MS-2 condition. The tendency of hot corrosion rate follows the order of, Base Metal MS-1 < K-PAW MS-1 < Base Metal MS-2 < K-PAW MS-2. The occurrence of protective phases like chromium oxides (Cr2O3), spinel oxides (NiCr2O4 and NiFe2O4) Nickel oxide (NiO) on the substrate resist the further oxidation.

In this work, Flash butt welding process was completely studied and the parameters for improvement of productivity were established with the help of flash butt welding machine. This work tries to confirm that an exploratory type of research is mostly preferred and analysis has to be done to achieve the end output. Quality affirmation and cost of value are the two significant variables that influence the efficiency of flash butt welding. To accomplish excellent quality and less cost of value different components that impact the welded joint and procedure are considered and comprehended. As commitment towards this point, an examination was done in the flash butt welding system. One of the fundamental goal of this investigation was to build up the imperfection free parameters. This was done initially by studying the different defects that occur in flash butt welded joints.

This investigation addresses the effect of exposure time applied through shot peening as one of the severe plastic deformation technique on mechanical behavior of Al 7075-T6 alloy. Shot peening induces hardened layer in the surface region due to work-hardening effect by shot peening. The specimen shot peened for 105 s (SP105) exhibited highest values of tensile strength (591 MPa), yield strength (550 MPa) and surface hardness (265 VHN) as compared with untreated specimen with 568 MPa, 504 MPa and 184 VHN respectively. The increment in tensile properties are due to rapid improvement in the surface work-hardening by virtue of peening treatment with 105 s duration. In contrast, the shot peened alloy exhibited lower percentage elongation and higher surface roughness as compared with untreated one. The surface morphology and roughness studies before and after the treatment analyzed by suitable characterization.

In these work AZ91 magnesium matrix composites reinforced with two weight fractions (5 and 10 wt. %) of TiB2 particulates were fabricated by cold chamber die casting process technique. The microstructure, density, hardness, mechanical properties of the specimens was investigated. Microstructure studies showed that fairly uniform distribution of reinforcements was achieved up to the weight fraction studied. As compared to base alloy AZ91, the hardness and tensile strength considerably increased with increasing reinforcement content. The presence of TiB2 particles improved the hardness around 24.4 %, compressive strength around 67.2% and the yield strength around 20%. The enormous amount of increment in the compressive strength due to the dislocation density created by the difference in thermal properties of matrix and composites and also due to the micro-pores presence in the composite.

The present work focuses on the processing and characterization of LPG cylinder made up of glass fibre reinforced composite (GFRC) material. The commercial steel LPG cylinder is difficult to handle due to more weight and easily corroded with moisture environment. To overcome this problem, composite material which has high specific stiffness, high specific strength, less weight and high corrosion resistance to moisture is used to fabricate the LPG cylinder. In this investigation, the LPG cylinder with dimensions of commercial 5 kg Steel LPG cylinder is made by filament winding technique. While fabricating, the fibres are wounded on the plastic inner container which is used as gas-tight in-liner. The specimens are prepared from the fabricated composite LPG cylinder. The material properties of composite materials are evaluated by the tensile test, compression test, flexural test, density test and impact test.

The rapid deficiency of fossil fuel resources encourages the research community to discover the sustainable alternate fuel, in order to overcome the fuel cost and also meet the stringent emission norms. In this connection, the current investigation explores the influence of cobalt chromate with significant potential of citronella biofuel for CI engine applications. In present investigation, the synthesized cobalt chromate nano additive blended with citronella biofuel with the help of magnetic stirrer for a period of 15 to 20 minutes on a volume basis. In this experimentation, various blend contractions are prepared as follows as 50ppm, 100ppm, and 150ppm to run the engine. The outcome results explore that the 100ppm cobalt chromate dispersion in biofuel has a significant increase in brake thermal efficiency as 2.9% than raw citronella biofuel.

In the automotive applications, the main functionality of the HVAC system includes heating, ventilation, and cooling or air-conditioning of the vehicle to achieve the desired indoor thermal comfort. In the current scenario, the conventional vapor compression based HVAC system is widely used. The typical refrigerants used to operate this equipment include HFCs and HFOs which are susceptible to cause an environmental hazard. This article aims to assess the performance of a hypothetical solar-driven thermoelectric based rotary desiccant wheel HVAC system (D-HVAC) to be used for automotive applications. The D-HVAC system uses the desiccant wheel to remove the latent heat, energy wheel to remove the sensible heat, evaporating coolers to achieve further cooling, the regeneration of the desiccant wheel by hot air and water as the refrigerant. In the case of a solar-driven-DHVAC system, solar energy is utilized for the regeneration of the desiccant wheel in place of hot air.

The economic growth of the company depends on the quality and delivery time of the components. The pursuit of new techniques is mandatory to maintain quick delivery time without compromising quality. Ergonomics is one such technique that helps to improve workstation productivity by reorganizing the workspace, changing the sequence in operations, up-gradation of machine tools, reducing operator fatigue, etc. The ergonomic study was performed in a tractor steering gearbox manufacturing unit. In the present work, an ergonomic assessment of the workstation is done. Ergonomics assessment includes RULA assessment and Work-place assessment helped to find out the factors influencing the work station to be in the alert zone. During the observation of base milling operation, the operator needs to clamp and de-clamp the steering box manually by using mechanical tools. Due to which operator feel more fatigue in the wrist and lower-arm position which reduces productivity.

In regions like Indian Subcontinent, Gulf or Saharan & Sub-Saharan Africa, where the sunshine is abundant almost all year round, air-conditioning is an important aspect of vehicles (passenger cars, buses etc.). Higher heat means higher cooling demand which in turn means bigger AC system. Like other auxiliaries, AC compressor is a parasitic load on the engine. The best way to beat heat and reduce cabin heat load is to stop heat build-up itself. The present paper explores one such means of reducing cabin heat build-up by leveraging latent heat properties of phase change materials and thus improving the air condition performance. With the help of a case study this paper aims at detailing comprehensive effect of phase change material (PCM) and its application on the heat build-up inside the cabin of a vehicle, the air conditioning cooling performance, the time required to achieve comfort temperature, work of compression performed by AC compressor and COP.

This paper deals with designing methodology of centrifugal type automatic decompression system (CADS) for small gasoline engine. CADS reduce the operator’s fatigue to start the engine. When engine cranked, CADS releases combustion pressure of the engine via opening of exhaust valve momentarily during compression stroke, which drastically reduces the hand pulling force required to start the engine with recoil starter unit. A 172 cc gasoline engine, which has applications in agricultural purposes, has been used for designing and development of CADS, which has to be installed at camshaft cam gear assembly of engine. With the new developed concept operator’s hand pulling force for starting the engine has been reduced to 41 % and henceforth durability of engine starting system increased significantly. In this paper detailed design approach has been discussed of working model of CADS.

Electric motor mounts resonate at high frequency in the range of 600 to 1000Hz with motor excitation frequency resulting in isolation performance deterioration. There is a selection process of motor mounts such that the force-transfer under transient torque reduced and also avoids high-frequency resonance. The rubber dynamic stiffness plays a significant role in excitation frequency. Rubber shape factor and compound directly contribute towards the dynamic stiffness properties of the mount. Isolation efficiency depends on force transfer to the body and resonance phenomenon. In this paper, the rubber shape of motor mounts, which affect progression characteristics as well as high-frequency resonance, is discussed. The wings-effect of rubber bushes discussed which can be tuned to get the desired frequency shift in order to avoid resonance.