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Cameras and image processing hardware are rapidly evolving technologies, which enable real-time applications for passenger cars, ground robots, and aerial vehicles. Visual odometry (VO) algorithms estimate vehicle position and orientation changes from the moving camera images. For ground vehicles, such as cars, indoor robots, and planetary rovers, VO can augment movement estimation from rotary wheel encoders. Feature-based VO relies on detecting feature points, such as corners or edges, in image frames as the vehicle moves. These points are tracked over frames and, as a group, estimate motion. Not all detected points are tracked since not all are found in the next frame. Even tracked features may not be correct since a feature point may map to an incorrect nearby feature point. This can depend on the driving scenario, which can include driving at high speed or in the rain or snow.

The need of weight reduction for fuel reduction and CO₂ regulations enforces the use of light-weight materials for structural parts also. The importance of reinforced composites will grow in this area. While the structural behavior and the simulation up to high strain-rate processes for those materials have been in the focus of investigation for many years, nowadays the simulation of high cycle fatigue behavior is getting important as well. Efficient fatigue analysis for metals was developed by understanding the microscopic behavior (crack nucleation and initiation) and bringing it to the macroscopic level by combining it with the matching test data (SN curves, etc.). Similar approaches can be applied to composite materials as well.

The Hybrid Cellular Automaton (HCA) algorithm is a generative design approach used to synthesize conceptual designs of crashworthy vehicle structures with a target mass. Given the target mass, the HCA algorithm generates a structure with a specific acceleration-displacement profile. The extended HCA (xHCA) algorithm is a generalization of the HCA algorithm that allows to tailor the crash response of the vehicle structure. Given a target mass, the xHCA algorithm has the ability to generate structures with different acceleration-displacement profiles and target a desired crash response. In order to accomplish this task, the xHCA algorithm includes two main components: a set of meta-parameters (in addition target mass) and surrogate model technique that finds the optimal meta-parameter values. This work demonstrates the capabilities of the xHCA algorithm tailoring acceleration and intrusion through the use of one meta-parameter (design time) and the use of Kriging-assisted optimization.

Simultaneous Localization and Mapping (SLAM) algorithms are extensively utilized within the field of autonomous navigation. In particular, numerous open-source Robot Operating System (ROS) based SLAM solutions, such as Gmapping, Hector, Cartographer etc., have simplified deployments in application. However, establishing the accuracy and precision of these ‘out-of-the-box’ SLAM algorithms is necessary for improving the accuracy and precision of further applications such as planning, navigation, controls. Existing benchmarking literature largely focused on validating SLAM algorithms based upon the quality of the generated maps. In this paper, however, we focus on examining the localization accuracy of existing 2-dimensional LiDAR based indoor SLAM algorithms. The fidelity of these implementations is compared against the OptiTrack motion capture system which is capable of tracking moving objects at sub-millimeter level precision.

Residual stress prediction arising from manufacturing processes provides paramount information for the fatigue performance assessment of components subjected to cyclic loading. The determination of the material model to be applied in the numerical model should be taken carefully. This study focuses on the estimation of residual stresses generated after deep rolling of cast iron crankshafts. The researched literature on the field employs the available commercial material codes without closer consideration on their reverse loading capacities. To mitigate this gap, a single element model was used to compare potential material models with tensile-compression experiments. The best fit model was then applied to a previously developed crankshaft deep rolling numerical model. In order to confront the simulation outcomes, residual stresses were measured in two directions on real crankshaft specimens that passed through the same modeled deep rolling process.

In order to explore approaches for improving object detection accuracy in intelligent vehicle system, we exploit super-resolution techniques. A novel method is proposed to confirm the conjecture whether some popular super-resolution networks used for environmental perception of intelligent vehicles and robots can indeed improve the detection accuracy. COCO dataset which contains images from complex ordinary environment is utilized for the verification experiment, due to it can adequately verify the generalization of each algorithm and the consistency of experimental results. Using two representative object detection networks to produce the detection results, namely Faster R-CNN and YOLOv3, we devise to reduce the impact of resizing operation. The two networks allow us to compare the performance of object detection between using original and super-resolved images. We quantify the effect of each super-resolution techniques as well.

Spot Welds are a category of welds used extensively in automotive structures, normally for metals. The fatigue analysis of such spot welds can be evaluated using (a) the Point 2 Point (P2P) method where a beam or bar is used to connect the 2 surfaces being joined, (b) a more modern approach where the 1D element is replaced with an “equivalent” brick element, or (c) a third approach that falls somewhere between where a “spider” and circular ring of elements, is used to represent the spot weld. In all 3 cases there is an assumption that the cross section is circular. For some specialist cases such as plastic connectors, the cross section is not circular so a new user defined weld is proposed. This paper will describe the approach that is based on the concept that a user generated tensor line can be used (equivalent to the theoretical Force/Moment to stress algorithms built into the P2P approach) along with special S-N curves create for different joint shapes.

Collaborative robots are more and more used in smart manufacturing because of their capability to work beside and collaborate with human workers. With the deployment of these robots, manufacturing tasks are more inclined to be accomplished by multiple humans and multiple robots (MH-MR) through teaming effort. In such MH-MR collaboration scenarios, the task distribution among the multiple humans and multiple robots is very critical to efficiency. It is also more challenging due to the heterogeneity of different agents. Existing approaches in task distribution among multiple agents mostly consider humans with assumed or known capabilities. However human capabilities are always changing due to various factors, which may lead to suboptimal efficiency. Although some researches have studied several human factors in manufacturing and applied them to adjust the robot task and behaviors.

In the high frequency range, the SEA method has been applied to air borne path with success to predict both internal and external sound environment. Nevertheless, structure-borne prediction is still at issue -especially for cars, in the range 200 to 2000 Hz- as results are widely dependant on subsystem partition and validity of various assumptions required by SEA. Experimental SEA test technique (ESEA), applied to car bodies, has brought to the fore that SEA power balanced equations could robustly describe structure-borne noise. To make ESEA predictive, the database of measured FRF is simply replaced and enlarged by synthesized data generated from a finite element (FE) model and a selected observation grid of nodes. This technique, called Virtual SEA (VSEA), has been presented at SAE/NVC 2003.

Many of the vehicle components are manufactured by sheet metal forming process together with joining methods like the spot or seam weld, which will cause work hardening and thermal deformations in the products. As result, undesirable residual stresses, uneven thickness distribution and weld notches can be generated in the final product. Since the fatigue life of an automotive component depends on the manufacturing effects, much care should be given on the estimation of the process effects. In this study, fatigue life of a vehicle suspension component is estimated with finite element methods with considering the stamping and welding process effects. Residual stress distribution due to work hardening and thermal deformation is obtained, and used in determining the fatigue life as the mean stress effect. The simulation result is compared with test result and it shows the fatigue life is affected much more by welding rather than stamping.

The paper discusses two methods to implement error compensation framework for NC machining. In the first case a novel real-time co-interpolator is utilized that has been developed and demonstrated on a machine tool equipped with an open architecture controller (OAC). The second solution features near-time reprocessing of the NC programs, that is more suitable for existing machining systems. A P-type, iterative learning control (ILC) algorithm is also presented for calculating the error compensation values. The paper concludes with the results of machining tests, showing the effectiveness of the error compensation methodologies.

This paper examines some key aspects of the manufacturing process that “ Transformation Induced Plasticity” (TRIP) steels would be exposed to, and systematically evaluate how the forming and thermal histories affect final strength and ductility of the material. We evaluate the effects of in-service temperature variations, such as under hood and hot/cold cyclic conditions, to determine whether these conditions influence final strength, ductility and energy absorption characteristics of several available TRIP steel grades. As part of the manufacturing thermal environment evaluations, stamping process thermal histories are included in the studies. As part of the in-service conditions, different pre-straining levels are included. Materials from four steel suppliers are examined. The thermal/straining history versus material property relationship is established over a full range of expected thermal histories and selected loading modes.

Due to alternate local heating and cooling (Thermal cycles) during welding, complex stresses occur and so residual stresses and angular distortion occur after welding. The residual stresses and angular distortion present in the welded components cause internal cracks and mismatching of welded automobile structures. Also the tensile residual stresses in area near the weldment may cause fractures under certain conditions whereas compressive residual stresses in the base plate may reduce buckling strength of structural members. Hence a welding system which is capable of predicting and acting according to it is the need of the hour. It is difficult to obtain a more reliable complete analytical solution to predict angular distortion and maximum residual stresses for a wide range of welding processes, materials and process parameters.

Superplastic forming (SPF) is a manufacturing process that can facilitate increased use of aluminum in automobile body structures. Despite considerable advantages with regards to formability and tooling costs, the process has been mostly limited to low volume production due to relatively long cycle times. This paper focuses on the development of a simulation capability to model a novel double-action mechanical pre-forming SPF process which can enhance formability as well as improve production efficiency by combining technology of hot stamping and conventional superplastic forming. A commercial explicit finite element analysis (FEA) code was adopted to establish feasibility of the forming process. The predictive accuracy of the FEA code was established in terms of thickness distribution and material drawn-in by correlating simulation results with experiments conducted with a deep draw die.

A math-based approach is now in use to reduce transmission control algorithm development time and prototyping iterations, and to improve transmission control algorithm and software quality. This paper will describe the application of this efficient approach to the development of a transmission control algorithm for production. The processes for algorithm design, closed-loop and rapid prototype testing, auto-code generation of production software, and potential hardware-in-the-loop verification are described with references to supporting development tools. This approach enables upfront, math-based development and performance assessment of transmission control algorithms and their interactions with other powertrain and vehicle control algorithms. Examples will illustrate the efficiency of the control algorithm development approach over a wide range of conditions.

A novel method to measure parallelism of press line under dynamic operation by using high speed digital image correlation (HSDIC) system is presented. The construction and working principle of the measurement system are studied. Target with mark field array is designed, which achieve the continuous measurement during slide moving. The data evaluation method was discussed in detail. The results demonstrate that the full-field digital image correlation is an effective method to quantify the parallelism of press line during the press line operation.

In automotive body manufacturing, there are two processes are often applied, Nominal Build and Functional Build. The Nominal Build process requires all individual stamping components meet their nominal dimensions with specified tolerances. While, the Functional Build process emphasizes more on the tolerances of the entire assembly as opposed to those of the individual stamped parts. The common goal of both processes is to build the body assemblies that meet the specified tolerances. Although there is strict tolerance specified for individual stamping parts the finished stampings frequently are released to assembly process with certain levels of dimensioning deviations, or they are within the specified tolerances but require heavy clamping during assembly. It is of high interest to predict the dimensional deviations in the stamping sub-assembly or body-in-white assembly process.

A modern aircraft wing contains many complex pipes and ducts which, amongst other functions, form the fuel management and bleed air systems. These parts are often fabricated from thin sheet material using a combination of forming and welding and the manufacturing process is predominantly manual requiring highly skilled labor. Since each wing may only contain one or two of each part type the product volumes are very low, typically a few hundred per year. This means that conventional mass production approaches used in, for example the automotive industry, are not economically viable and the parts are thus disproportionately expensive. The current fabrication process involves splitting the component into parts that can be press formed from sheet, laser trimmed and then manually welded together in a fixture. This process requires a perfect fit between the parts whose quality is reliant on the initial forming process.

Damaged or discrepant holes in metal and composites aircraft are time consuming and expensive to repair. Bushing the hole back to nominal size using press or shrink fit bushings; often in conjunction with doublers or local riveted patches, are not very effective and can change the local stiffness of the structure. Using a cold expanded high interference ForceMate repair bushing is a more cost effective alternative that has the advantage of not altering the local stiffness or dynamic response of the repair location while locally cold working the surrounding material to enhance the life and damage tolerance of the repair. A ForceMate2 panel repair method has been adapted to repair elongated or oversized holes in thin panel structures or removable access panels. This paper describes the methods and discusses testing and evaluation done to qualify the repairs in structural or panel repair applications.

P/M parts are often machined after sintering to meet tight dimensional tolerances or accommodate design features that cannot be molded during compaction. The development of new polymeric lubricants opens the possibility of machining P/M components prior to sintering, which could result in a considerable reduction of machining costs. This study compares the green and ejection characteristics of binder-treated FC-0205 mixes containing either a new high green strength lubricating system or conventional EBS wax. The comparison was carried out on TRS specimens and gears pressed from 6.8 to 7.2 g/cm3 on laboratory and production scale presses. The influence of these lubricating systems on green machining was also determined on gear shape specimens pressed to 6.8 and 7.0 g/cm3. Results showed that mixes containing the new lubricating system exhibit similar compressibility and a better lubrication behavior than mixes admixed with the conventional EBS wax.