News Article | December 3, 2015
« Navigant forecasts annual fuel cell vehicles sales to exceed 228,000 units by 2024 | Main | Boeing, Canadian aviation industry launch sustainable aviation biofuel project using forestry waste » General Motors is applying third-generation advanced high-strength steel to the new Chevrolet LOVA RV from SAIC-GM, thereby reducing the weight of selected body components by approximately 20%. The recreational vehicle (RV) was launched on 19 November 2015. The new steel offers a superior balance of strength and ductility as compared to the first generation of high-strength steels. The fuel economy of a vehicle is generally considered to increase by 6 to 8% for every 10% reduction in body weight. In 2009, GM began encouraging steel manufacturers to produce third-generation advanced high-strength steel with superior formability and tensile strengths of 1,000 MPa and higher for vehicle bodies. Among all the state-of-art steel-making processes, the GM China Science Lab in Shanghai identified the Quench and Partition (Q&P) process as one of most promising solutions for producing third-generation advanced high-strength steel.cQ&P steel represents a new type of ultrahigh-strength steel with good ductility to improve fuel economy while promoting passenger safety. With a final microstructure of ferrite (in the case of partial austenitization), martensite, and retained austenite, Q&P steel exhibits an excellent combination of strength and ductility. Through a specially-designed quenching and partitioning treatment, retained austenite can be stabilized in the steel microstructure at room temperature, which significantly improves the formability of steel. In 2011, GM China Science Lab joined GM’s Pan Asia Technical Automotive Center (PATAC) joint venture, Baosteel and Tongji University to establish an expert team to develop solutions for introducing Q&P steels into GM vehicles. Research groups within the GM China Science Lab, GM China Advanced Technical Center (ATC), and the GM Warren Technical Center in the United States collaborated on research and development of third-generation advanced high-strength steel. This global development network was instrumental in the successful implementation of the advanced steel technology in GM vehicles. In the past, nearly 25 years of research and development were required to go from initial steel development concepts to production of the first-generation high-strength steels such as dual-phase steel. Through open innovation, GM and its partners have been able to shorten significantly the concept-to-production process of third generation steels. GM has also contributed significantly to the application of key technologies by studying materials, microstructures and assessing their performance. Findings from these investigations are now being applied to the development of third-generation 1,200 MPa Q&P steel. In addition, assessment methods that precisely measure the performance of third-generation advanced high-strength steel, especially in terms of crashworthiness, have been adopted by a number of steelmakers. Technical learnings such as these are being shared worldwide within GM and will be instrumental to future applications of third-generation steels in GM vehicles around the globe.
Xing Y.,Shanghai University of Engineering Science |
Hu M.,Pan Asia Technical Automotive Center |
Zeng H.,Pan Asia Technical Automotive Center |
Wang Y.,Shanghai University of Engineering Science
International Journal of Production Research | Year: 2015
Auto-body compliant parts are easily deformed during clamping and welding, and fixture layout is very important to the final product quality. However, it is very difficult to design fixture layout because it needs to synchronously satisfy the requirements of assembly tolerance and gravity deformation, which are calculated by finite element analysis. This paper proposes a new method to optimise fixture scheme by a non-domination sorting social radiation algorithm (NSSRA). Firstly, unfeasible nodes are eliminated by four rules according to manufacturing experiences. Afterwards, a few groups are divided based on positions of all feasible nodes. N groups are optimised using NSSRA. Finally, the best fixture layout is generated by selecting the feasible points among the optimal groups in last step. A case study of inner hood is used to illustrate the proposed method, and the results suggest that NSSRA has better efficiency and higher accuracy than NSGA-II. © 2015 Taylor and Francis.
Lin C.,Beijing Institute of Technology |
Xu Z.,Beijing Institute of Technology |
Zhang R.,Pan Asia Technical Automotive Center
Mathematical Problems in Engineering | Year: 2015
A hierarchical control algorithm of direct yaw moment control for four-wheel independently actuated (FWIA) electric ground vehicles is presented. Sliding mode control is adopted to yield the desired yaw moment in the higher layer of the algorithm due to the possible modeling inaccuracies and parametric uncertainties. The conditional integrator approach is employed to overcome the chattering issue, which enables a smooth transition to a proportional + integral-like controller, with antiwindup, when the system is entering the boundary layer. The lower level of the algorithm is given to allocate the desired yaw moment to four wheels by means of slip ratio distribution and control for a better grasp of control boundaries. Simulation results, obtained with a vehicle dynamics simulator, Carsim, and the Matlab/Simulink, show the effectiveness of the control algorithm. © 2015 Cheng Lin et al.
Cao L.,State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body |
Chen H.,State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body |
Ren X.,Pan Asia Technical Automotive Center |
Ouyang Z.,State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body
Applied Mechanics and Materials | Year: 2010
A new integrated child safety seat is presented in this paper. The seat is a two-mode seat for a motor vehicle cooperable with an adult seat belt assembly to provide two modes operation including an adult seat mode and a child seat mode. The seat locates in the center of the rear seat. The structure of the seat was designed in detail. The height of the booster of the seat can be adjusted continuously according to the seated shoulder height of the child passenger. The depth of booster cushion also can be changed according to the size of the passenger. The sled test with the seat was conducted. The seat simulation models with different booster heights were developed using MADYMO software and validated. Then, these models were used to study the performance of the seat in frontal impact. Some key parameters of the seat were studied in simulation test. The results of the test and simulation show that the seat can provide effective protection for the children aged from 3 to 10 years in frontal impact. © (2010) Trans Tech Publications.
Li C.,Wuhan University of Technology |
Deng Y.,Wuhan University of Technology |
Xin Y.,Pan Asia Technical Automotive Center
SAE Technical Papers | Year: 2016
As a key component of airstream system equipped in the road sweeper, the structure of the suction nozzle determines its internal flow field distribution, which affects the dust-sucking efficiency to a great degree. This research is aiming to determine a better suction nozzle structure. Starting with an analysis of the one used in a certain type of road sweeper, the initial model of the suction nozzle is established, and the internal flow field is simulated with typical computational fluid dynamics (CFD) software named FLUENT. Based on the simulation results, the dust-sucking capability of the initial structure is evaluated from the aspects of pressure and velocity distribution. Furthermore, in order to explore the influence of different structural parameters on the flow field distribution within the suction nozzle, models with different cavity heights and shoulder angles are established, and Univariate Method is utilized to analyze the contrast models. The model with chamfering is also studied in the same way. Based on these simulation results, an optimized scheme of the initial structure is proposed. Moreover, the simulation of two-phase flow in the optimized structure is completed on the basis of discrete phase model (DPM), the particle trajectory is tracked and the result shows a significantly better dust-sucking effect with a more reasonable pressure field and velocity field in comparison with the initial model. Through present researches, the structure of the suction nozzle is expected to be improved, and it also provides a design reference for the development of high efficiency road sweepers. © 2016 SAE International.
Tian H.,Pan Asia Technical Automotive Center |
Chen P.,Pan Asia Technical Automotive Center
Lecture Notes in Electrical Engineering | Year: 2013
Lever analogy is very useful in analyzing gear-train including more than one planetary gear sets. The lever analogy is a translational-system representation of the rotating parts for the planetary gear. Applying lever analogy to GM 6T40E transmission, kinematic and dynamic analysis is shown in this paper. Model based shift control strategy is based on dynamic lever analogy. By setting target output torque and desired turbine speed profile, the clutch pressure and torque request to engine can be commanded. With more investigation on lever analogy, enhanced control strategy and new function are already invented. © Springer-Verlag 2013.
Ming D.,Pan Asia Technical Automotive Center
Lecture Notes in Electrical Engineering | Year: 2013
Research and/or Engineering Questions/Objective: Active headrest is usually utilized to mitigate the whiplash injury to the occupant from the rear impact by way of moving forward during the collision to shorten the distance and the contact duration between the occupant head and the headrest thus reduce the neck injury index. But the spread application of the active headrest is limited due to its high cost. This paper explore the approach of applying a passive head restraint to alleviate the whiplash injury during the rear impact. Methodology: Aimed at earning high rating of GOOD in the rear impact condition in IIHS through minimize the neck injury, this paper presents the method of development and optimization of head restraint insert/surface and seat back suspension and the by way of simulation and vehicle test. Results: The rigidity distribution of seat back suspension, and quality of the integration design of head restraint foam and insert have great impact to the neck injury resulted from the rear collision. In order to keep the seat comfort, a space between the occupant head and the head restraint surface has to be maintained. In the premise of satisfying the seat comfort to the greatest extend, by way of adjusting seat back suspension and the head restraint insert/surface, the head restraint can rapidly contact the occupant head in the collision, thus reduce the shear load and tension to the neck, and earning highest rating of GOOD in IIHS. Limitations of this study: This paper study the rear impact load case of IIHS only, does not consider 2012 version CNCAP and Euro NCAP. But the approach set forth in this article can be applicable for mitigate the neck injury in the rear impact. What does the paper offer that is new in the field in comparison to other works of the author This paper study the development and optimization of passive head restraint to improve the occupant protection performance of the head restraint in the rear impact with the minor cost increase. The paper offers the active contribution in lower the cost and the vehicle mass. Conclusion: In the premise of satisfying the seat comfort to the greatest extend, by way of adjusting head restraint insert/surface and seat back suspension, the headrest can rapidly contact the occupant head in the collision, thus reduce the shear load and tension to the neck, and earning highest rating of GOOD in IIHS. This paper study the development and optimization of passive head restraint to improve the occupant protection performance of the headrest in the rear impact without increase the cost. The paper offers the active contribution in lower the cost and the vehicle mass. © Springer-Verlag 2013.
Hu X.,Pan Asia Technical Automotive Center |
Liu Y.,Pan Asia Technical Automotive Center |
Zhu L.,Pan Asia Technical Automotive Center
AIP Conference Proceedings | Year: 2013
Advanced high strength steel is the basic structure material for lightweight design and safety enhancement for automobile industry. Quenching and partitioning steel is a recently developed kind of low carbon and low alloy material with retained Austenite for the requirements of both high strength and high ductility. This paper focuses on the formability of a hinge pillar for some car under numerical modelling analysis. The results show that QP980 has an equal elongation comparing with DP590. Moreover, the numerical modelling results of QP980 are more sensitive to the selection of yielding equation comparing with DP590. © 2013 AIP Publishing LLC.
Dai H.,Tongji University |
Guo P.,Tongji University |
Wei X.,Tongji University |
Sun Z.,Tongji University |
Wang J.,Pan Asia Technical Automotive Center
Energy | Year: 2015
A common drawback of the SOC (State of Charge) estimators of EV (electric vehicle) traction batteries nowadays is that they don't consider the difference among individual cells and employ the "averaged SOC" as the state of charge of the pack. Over-charge or over-discharge may happen to the weak cells with this SOC value in vehicular applications. In this study, a novel approach for online pack SOC estimation and correction is proposed, which combines a traditional SOC estimator and an ANFIS (adaptive neuro-fuzzy inference system). The traditional KF (Kalman filtering) based estimator is applied to firstly estimate the "averaged SOC" of the battery pack, and the ANFIS is then used to online correct the "averaged" SOC estimation with the information of cell differences and loading current. The influence of cell differences on SOC estimation is embodied in the fuzzy rules of the ANFIS, which is trained offline. Validation results by experiments show that, the proposed method has the potential to overcome the drawbacks of traditional SOC estimators caused by cell-to-cell variations in a battery pack, and the corrected SOC is more reasonable than the traditional "averaged SOC". © 2014 Elsevier Ltd.
News Article | November 3, 2016
« BMW has sold more than 100,000 EVs and PHEVs worldwide over three years | Main | GM demos 8 connected vehicle safety applications in Shanghai » Buick’s plug-in hybrid Velite Concept will make its global debut at the Guangzhou auto show, which opens on November 18. The Velite Concept will provide a template for upcoming models being launched under the Buick Blue new energy vehicle strategy. The development of the Velite Concept was led by the Pan Asia Technical Automotive Center (PATAC), GM’s engineering and design joint venture in Shanghai with SAIC, leveraging GM’s global resources. The Velite Concept is powered by a high-performance plug-in hybrid electric vehicle (PHEV) powertrain that is effective, responsive and smooth. Its SIDI engine is paired with GM’s latest modular intelligent electric drive system and a high-performance modular lithium-ion battery pack, which work together to optimize efficiency under varying driving conditions. The introduction of the Velite Concept follows August’s global debut of the Buick LaCrosse Hybrid Electric Vehicle (HEV) in Shanghai. (Earlier post.) Additional products featuring HEV, PHEV and extended-range electric vehicle (EREV) powertrains are on the way from Buick to provide diverse intelligent solutions for green mobility. Buick has sold more than 7 million vehicles in China since its introduction by SAIC-GM in 1998.