Browse Topic: Dual clutch transmissions
Evaluating the impact of software changes on fuel consumption and emissions is a critical aspect of transmission development. To evaluate the trade-offs between performance improvements and potential negative effects on efficiency, a forward-looking Software-in-the-Loop (SiL) simulation has been developed. Unlike backward calculations that derive fuel consumption based solely on cycle speed and engine speed, this approach executes complete driving cycles as the Worldwide Harmonized Light-Duty Vehicle Test Cycle (WLTC) within a detailed SiL environment. By considering all relevant influencing factors in a dynamic simulation, the method provides a more accurate assessment of fuel consumption and emission differences between two versions of the transmission software. The significant contribution of this work lies in the high-fidelity integration of a real virtual Transmission Control Unit (vTCU) software within a comprehensive, validated forward-looking SiL environment. This approach enables precise delta comparisons that capture transient dynamic interactions, facilitating early, reliable software testing and validation.
The torque transfer response to rider throttle operation contributes to vehicle control in motorcycles equipped with a DCT (Dual Clutch Transmission). The clutch response is a key parameter to enhance torque transfer response. We have developed three new ECU (Electric Control Unit) control methods to enhance the clutch response on the DCT. The DCT clutch transfers torque by controlling the contact force between the clutch discs and the clutch plates. It is desirable to measure the hydraulic pressure value directly from the clutch piston chamber to control the contact force. However, since the clutch piston is a rotating body, it is impractical to place a hydraulic pressure sensor on it. Therefore, the hydraulic pressure sensor is placed along the clutch control oil line at the existing DCT system. Consequently, when oil flows in the oil line, pressure loss in the oil line causes a deviation between the hydraulic pressure sensor value and the clutch piston chamber pressure value, which limits the enhancement of clutch response. To enhance clutch response, we have studied the estimation of the hydraulic pressure value in the clutch piston chamber using the existing hydraulic pressure sensor value at the oil line. This estimation is based on the reaction force characteristics of the clutch piston and Bernoulli’s principle. By using the estimated hydraulic pressure, half-clutch control can be identified, which allows the application of higher feedback gain to enhance clutch response. We also implement correction of clutch control oil viscosity fluctuations based on the hydraulic pressure variations of the clutch control oil. With these technologies applied, the clutch response time is reduced 45% as reference compared to the existing DCT clutch control. This also reduces torque transfer response time, ultimately allowing for smoother vehicle control.
Dual Clutch Automatic Transmission (DCT) has the characteristics of light weight, fast shift speed and high transmission efficiency. Electric vehicles equipped with dual clutch transmission can effectively improve vehicle power performance and economy. Electro-hydraulic control system, as a key component of transmission, determines the quality of shift. In this paper, an electro - hydraulic control system is designed based on two - speed dry dual clutch transmission of electric vehicle. Firstly, the hydraulic components of the system were selected and calculated based on the vehicle parameters. Secondly, the electro-hydraulic control system of the dual clutch transmission was established according to the transmission control strategy and the matching hydraulic valve body assembly was designed. Then, the key components of the system were simulated to analyze their dynamic shift characteristics and response characteristics. Finally, through various tests, it is verified that the designed electro-hydraulic control system and transmission meet the design requirements. The results show that the electro-hydraulic control system can meet its working characteristics and shift requirements.
Shift fork is a key shifting element in manual and dual clutch transmission for smooth operations of gear shifting. One of the main criteria for robust design of shift fork is stiffness symmetry. Stiffness symmetry ensures straight movement of sleeve onto hub and thus helps in achieving good shift quality. Stiffness symmetry also ensures equal load distribution across two or three pads of shift fork while in operation. In this paper, we intend to demonstrate finite element simulation driven design process to improve stiffness symmetry of shift fork. Various parameters affecting stiffness symmetry are analyzed through design of experiment and selected best range for optimum design of shift fork. Output of this study will be useful for improving any design of shift fork to meet different targets of stiffness symmetry for all automobile suppliers and manufactures.
Synchronizers are shifting elements in transmissions with power interruption, such as manual transmissions (MT) and automated manual transmissions (AMT). Synchronizers are also used in dual clutch transmissions (DCT) for shifting the preselected idler gear in the load-free branch of the transmission. Electric drive units (EDU) mainly consist of a two-stage transmission combined with a high-speed electric motor. Synchronizers realize the power flow from an idler gear to a gear shaft of the transmission. Automotive transmissions are usually operated with lubricating oils in order to minimize friction and wear of the mechanical components. Lubricating oil has a major influence on torque losses and on vibration behavior of transmission components. Torsional vibrations of mechanical components in transmissions lead to natural vibrations with high impact forces and thus to high radiated airborne sound levels. This occurs in particular when hard surfaces impact and the components have a high level of spring stiffness in addition to low damping properties. A drive torque that has a rotational irregularity leads to torsional vibrations of the components outside the power flow and is the starting point for transmission noises. Synchronizers have a function-related circumferential backlash in order to be able to shift the gear in a synchronized manner and therefore contribute to undesirable transmission noises. The aim of this work is to measure the vibrations of a synchronizer ring due to torsional vibration excitation while varying various parameters and to show the influences of the parameters. In particular, the lubricating oil has an influence on the torque losses and on the vibration behavior of a synchronizer. Lubricating oil with a low coefficient of friction due to its chemical structure leads to lower torque losses of the synchronizer and reduces the vibrations, which leads to a 1-2 dB(A) lower noise level of the transmission.
Demand for electrified vehicles is increasing due to increased environmental pollution regulations and interest in highly efficient vehicles. According to these demands, research on electrified vehicles equipped with Dual Clutch Transmission (DCT) has been actively conducted for the purpose of improving energy efficiency of electrified powertrain, maximizing acceleration performance, and increasing maximum speed. However, since DCT requires clutch to clutch shifting, it is difficult to control drive torque and slip speed using two clutch actuators and a power source input. In order to solve this, a study on a multivariable shift controller has been conducted. However, this study chose a heuristic planning method to control the two outputs. However, since the slip speed and drive torque are coupled, it is necessary to tune the reference for every shift scenario, as well as create unnecessary control inputs or degrade shift control performance. Therefore, this study proposes a reference planning method considering powertrain dynamics. Specifically, by using the powertrain modeling of the electrified vehicle, a reference composed of power source input, slip speed, and drive torque can be constructed while satisfying dynamics. Using the proposed method, the slip speed is uniquely determined when the reduction ratio of the power source torque and the inertia phase time are predetermined. In order to verify the proposed planning method in this paper, an electrified powertrain simulator designed with a multivariable controller was constructed with MATLAB/SIMULINK. Afterwards, the heuristic reference planning method of the previous study and the method proposed in this paper were simulated in a vehicle composed of the same shift controller and powertrain. As a result, not only the reference automatically generated without tuning, but the energy consumption of the clutch actuator is reduced by about 10% in the control result with the same ride quality.
To address the difficulties in modeling the starting process of dual-clutch transmission (DCT) vehicles and poor adaptability of vehicles in complex driving conditions, this article proposes a new modeling and control strategy for the DCT starting system based on data-driven autoregressive moving average exogenous (ARMAX) modeling. Firstly, the DCT starting process is considered equivalent to the time series-related ARMAX model, and a data-driven ARMAX model could be obtained using input-output data relating to the starting process; also, the effectiveness of the data-driven ARMAX modeling technique is verified using the starting test of a real vehicle. Secondly, a data-driven adaptive model predictive control (A-MPC) strategy, which synthetically considers driving intention and clutch engagement status, is proposed. Finally, in order to verify the proposed control strategy, simulation analysis is conducted in different intentions; the results show that the proposed control strategy could realize the starting control effectively, and reflect driving intention. Compared with model predictive control only considering driving intention, the proposed control strategy could improve starting performance in different intentions; also, compared with the conventional control method, the A-MPC can improve the starting performance.
The dual clutch transmission is one of the possible choices for electric vehicle drivelines. The basic principle and control mode of shifting of wet dual clutch transmission are introduced, and the dynamic process of shifting of wet double clutch transmission is studied. Combined with the dynamic model of the wet clutch engagement process, the difference between the dynamic characteristics of the dual clutch transmission modeling using the Coulomb friction model and the dual-clutch transmission model using the average flow model and the micro-convex contact theory is analyzed. The shift control strategy of the dual clutch transmission proposes a correction method to improve the shifting smoothness. Studies have shown that the torque response of the wet clutch has significant hysteresis, and the improved control algorithm can significantly improve the shifting smoothness of the wet dual clutch transmission. Based on the dynamic model of the wet clutch, the torque interruption of the shift control strategy of the dual clutch transmission is studied, and the method of improving the shift smoothness by the correction of the shift control strategy is proposed.
Today, the contribution of the transportation sector on greenhouse gases is evident. The fast consumption of fossil fuels and its impact on the environment have given a strong impetus to the development of vehicles with better fuel economy. Hybrid electric vehicles fit into this context with different targets, starting from the reduction of emissions and fuel consumption, but also for performance and comfort enhancement. Lamborghini has recently invested in the development of a hybrid super sport car, due to performance and comfort reasons. Aventador series gearbox is an Independent Shift Rod gearbox with a single clutch and during gear shifts, as all the single clutch gearbox do, it generates a torque gap. To avoid the additional weight of a Dual Clutch Transmission, a 48V Electric Motor has been connected to the wheels, in a P3 configuration, to fill the torque gap, and to habilitate regenerative braking and electric boost functions. This paper discusses the usage of a control-oriented vehicle and powertrain model to analyze the performance of the first Lithium Ion Capacitor-based hybrid V12 by Automobili Lamborghini. The internal combustion engine, the gearbox, the LiC and the vehicle longitudinal dynamics models have been initially validated through the comparison with experimental data from chassis dynamometer testing, in addition to experimental results from specific components’ testing. As shown in the paper, the validated model has then been used to develop control strategies aimed at increasing comfort and performance, but also to expand the hybrid system capabilities by widening the LiC working range, and to study the possibility of implementing CO2 reduction-oriented control functions.
The following schematic diagrams reflect various methods of illustrating automotive transmission arrangements. These have been developed to facilitate a clear understanding of the functional interrelations of the gearing, clutches, hydrodynamic drive unit, and other transmission components. Two variations of transmission diagrams are used: in neutral (clutches not applied), and in gear. For illustrative purposes, some typical transmissions are shown.
This paper explores the effects of maneuvering and gust loads on the drive system and flight dynamic response of a single main rotor helicopter equipped with a two speed dual clutch transmission. The authors demonstrate that performing upshifts during certain maneuvers can significantly reduce the transmitted clutch frictional torques and the resulting clutch pack temperature rise during gear changes. For example, compared with an upshift in level flight, performing a 8° pitch-up maneuver reduced peak clutch frictional power dissipation by 63% (from 455 Hp down to 169 Hp) and reduced total upshift time by 37% (from 5 seconds down to 3 seconds). This results in an 83% reduction in total heat energy dissipated by the clutch during the upshift. Since the design of the clutch pack mass is directly proportional to the heat dissipation requirements, this new (Maneuver Assisted Shifting) MAS technique could enable significant weight savings and clutch wear reduction in helicopter two-speed transmissions.
A novel magnetorheological fluid dual clutch (MRFDC) for electric vehicle transmission is proposed in this article. The structure was based on the MR fluid clutch and traditional dual clutch equipped on internal combustion engine vehicle. Therefore the MRFDC combines the advantages of MR fluid clutch and dual clutch transmission (DCT) to achieve high control accuracy and fast response. The structure of MRFDC was designed by Unigraphics (UG) three-dimensional (3D) modeling software. Then, finite element analysis (FEA) for magnetic field was conducted by ANSYS under different applied currents from 0.1A to 1A with 0.1A space to obtain the relation between the applied current and magnetic field. In this article, Herschel-Bulkley model is used to predict the MR fluid behavior because of the high shear rate of MR fluid. Finally, output torque of MRFDC can be estimated by calculus with geometric dimensions of MRFDC structure and rheological properties of MR fluid dependent on the magnetic field generated by the applied current. Finally the relation between the applied current and output torque of the internal clutch and external clutch can be obtained, respectively. Simulation results show that the relation between the output torque and the applied current can be considered linear for internal clutch under 0-1.0A current excitation. While the applied current is below 0.3A, the relation for external clutch can also be considered as linear. Thus, it is easy to use linear control methods to achieve gear shift based on mathematical models of MRFDC by controlling the applied current through the coil of the dual clutch under the requirement of achieving the maximum driving torque.
This paper examines the effect of pulse-and-glide (PnG) driving strategies on the fuel efficiency when applied on parallel HEVs. Several PnG strategies are proposed, and these include the electrical, mechanical, and combined PnG strategies. The electrical PnG strategy denotes the hybrid powertrain control tactics in which the battery is charged or discharged according to the power demanded while maintaining the constant vehicle speed. On the other hand, the mechanical PnG strategy denotes the powertrain control tactics in which the vehicle accelerates or decelerates according to the power load while minimizing the battery usage. The combined PnG strategy involves both electrical and mechanical strategies to find a balanced point in between them. Here, a tradeoff relationship between the fuel efficiency and the vehicle drivability related to the tracking performance of the desired target speed is revealed. In the assessment of the feasibility of applying each of the formerly mentioned hybrid driving strategies, the causes of driveline heat loss are recorded and analyzed by their types. These include the engine heat loss, engine friction loss, motor loss, and the resistance loss. The motor loss includes all of the electrical energy loss induced in the powertrain electronics, and the resistance loss includes the loads acting on the vehicle such as the aerodynamic drag and rolling resistance. These factors are quantitatively analyzed for different driving strategies along with the related fuel efficiency in an integrated manner. The experimental validation is conducted using a real HEV equipped with a gasoline spark-ignition engine, transmission-mounted electric drive, and a 6-speed dual clutch transmission.
An online and real-time Condition Prediction system, so-called lifetime monitoring system, was developed at the Institute for Mechatronic Systems in Mechanical Engineering (IMS) of the TU Darmstadt, which is intended for implementation in standard control units of series production cars. Without additional hardware and only based on sensors and signals already available in a standard car, the lifetime monitoring system aims at recording the load/usage profiles of transmission components in aggregated form and at estimating continuously their remaining useful life. For this purpose, the dynamic transmission input and output torques are acquired realistically through sensor fusion. In a further step, the lifetime monitoring system is used as an input-module for the introduction of innovative procedures to more load appropriate dimensioning, cost-efficient lightweight design, failure-free operation and predictive maintenance of transmissions. This is based on damage-oriented operating strategies (so-called eLIFE) and a paradigm shift in the design philosophy relying on a smart big data approach (so-called ecoLIFE3 design procedure). The paper will present the lifetime monitoring system by the example of two concrete application cases, namely a manual and a dual clutch transmission (DCT). Furthermore, the concepts of eLIFE and ecoLIFE3 will be introduced and the economic and ecologic potentials of the approach will be discussed and quantified on basis of a DCT.
The reduction of CO2 emissions at vehicle level through the improvement of transmission efficiency represents the essential goal of transmission development engineers. New requirements, such as the recovery of the kinetic energy of the vehicle while coasting, the hybridization of drivetrains and autonomous driving, are challenges that can best be overcome with automatic transmissions. Dual clutch transmissions (DCT) with power-on-demand actuation systems offer a particularly efficient method of meeting the new requirements. However, many markets show vehicle applications with production volumes of less than 100.000 units per year. FEV’s new DCT family is conceived especially for customers in these markets. The re-use of proven subsystems which are already in series production results in a "business case" for applications with lower volumes also. This article introduces this transmission family.
An MIT student-inventor's clutchless hybrid transmission concept aims to provide high-performance vehicles an energy-saving attitude without compromise. The concept mechanism uses an electric motor to fill the acceleration lag that occurs when a driver releases the throttle and engages the clutch. A second electric motor is used for quickly speed-matching the gears during the shift since there is no mechanical means to speed up the next gear before engaging it.
Regenerative braking has been widely accepted as a feasible option to extend the mileage of electric vehicles (EVs) by recapturing the vehicle’s kinetic energy instead of dissipating it as heat during braking. The regenerative braking force provided by a generator is applied to the wheels in an entirely different manner compared to the traditional hydraulic-friction brake system. Drag torque and efficiency loss may be generated by transmitting the braking force from the motor, axles, differential and, specifically in this paper, a two-speed dual clutch transmission (DCT) to wheels. Additionally, motors in most battery EVs (BEVs) and hybrid electric vehicle (HEVs) are only connected to front or rear axle. Consequently, conventional hydraulic brake system is still necessary, but dynamic and supplement to motor brake, to meet particular brake requirement and keep vehicle stable and steerable during braking. Therefore, a complicated effect on the safety and performance of braking, mainly relating to tyre slips and locks, vehicle body bounces and braking distance will be applied by the blended brake system. In this paper, the brake energy recovery potentials of typical driving cycles are presented. Relevant critical limitations are introduced to define the available brake force distribution range for front and rear axles. Then the distribution strategies are compared and analyzed to achieve a satisfied balance between braking performance, driving comfort and energy recovery rate. Next, the required motor brake force is tuned, according to the response time and efficiency loss in transfer process which obtained in testing bench. At last, solutions for some special cases are proposed, for instance, motor brake torque interruption when downshifting occurs on long downhill. A credible conclusion is gained, through experimental validation of optimized brake force distribution strategy on a two-speed DCT based BEV testing rig, that the selected force distribution strategy help the blended brake system achieve a comfortable and safety braking during all driving conditions.
This paper presents a methodology for the assessment of the NVH (noise vibration and harshness) performance of Dual Clutch Transmissions (DCTs) depending on some transmission design parameters, e.g. torsional backlash in the synchronizers or clutch disc moment of inertia, during low speed maneuvers. A 21-DOFs nonlinear dynamic model of a C-segment passenger car equipped with a DCT is used to simulate the torsional behavior of the driveline and to estimate the forces at the bearings. The impacts between the teeth of two engaging components, e.g. gears and synchronizers, generate impulses in the forces, thus loading the bearings with force time-history characterized by rich frequency content. A broadband excitation is therefore applied to the gearbox case, generating noise and vibration issues. The metric used to assess the severity of a specific test and to compare, at least qualitatively, the NVH performance related to different design parameters sets, is based on the RMS (root-meansquare) value of each bearing force time-history. Variations from one test to another allow assessing the benefit introduced by specific design parameter modifications. Applications of the proposed methodology aimed at evaluating the effects of reducing the clutch discs moment of inertia, the synchronizers backlash and the internal backlash in the differential are presented. Finally the paper shows that results not only depend on the gearbox design but also on the specific maneuver chosen to excite the dynamic system under test: a clear trend may be seen in some cases while only negligible effects are observed in other conditions.
Dry dual clutch transmission (DCT) has played an important role in the high performance applications as well as low-cost market sectors in Asia, with a potential as the future mainstream transmission technology due to its high mechanical efficiency and driving comfort. Control system simplification and cost reduction has been critical in making dry DCT more competitive against other transmission technologies. Specifically, DCT clutch actuation system is a key component with a great potential for cost-saving as well as performance improvement. In this paper, a new motor driven clutch actuator with a force-aid lever has been proposed. A spring is added to assist clutch apply that can effectively reduce the motor size and energy consumption. The goal of this paper is to investigate the feasibility of this new clutch actuator, and the force-aid lever actuator's principle, physical structure design, and validation results are discussed in details. A prototyping of the proposed system is developed for the engagement of the clutch with a position-tracking controller. The advantages of the design and the performance of the control system developed are demonstrated through bench testing. It can be a promising low-cost clutch actuation system for a DCT transmission
Dual Clutch Transmissions (DCT) for passenger cars are being developed by OEMs and suppliers. The driving force is the improvement in fuel economy available from manual transmissions together with the comfort of automatic transmissions. A dry clutch system (dDCT) is currently the subject of research, development, and production implementation. One of the key issues in the development of a dDCT is clutch durability. In dry clutches with current linings, above a critical temperature, the friction system starts to suffer permanent damage. In addition, the clutch friction characteristics are a function of the clutch interface temperature. Because a reliable, low-cost temperature sensor is not available for this application, the clutch control engineers rely on a good thermal model to estimate the temperature of the clutches. A thermal model was developed for dry dual clutch transmissions to predict operating temperature of both pressure and center plates during all maneuvers. The model is intended to be used to a) prevent clutch plate over-heating during abusive driving scenarios such as hill holding or multiple GCVW launches in both forward and reverse on grades and b) estimate clutch friction characteristics for control purposes. It is a Simulink based model that is integrated into the transmission controller to notify drivers and take corrective actions in case of overheating. The model also predicts the initial conditions for the temperature of the clutches during engine startups. The thermal model was validated fully in a test cell environment as well as in vehicles using slip ring and telemetry hardware. The thermal model has seven states that include both bell housing air and skin temperatures. Other parameters that affect cooling performance of a dry DCT, such as ambient temperature, and engine coolant and transmission oil temperatures, are also taken into consideration.
In this paper, a new algorithm for the off-line estimation of wet clutch friction parameters is proposed for automotive transmissions, motivated by the usefulness of such an algorithm for diagnosing the condition of the clutch and transmission fluid in service. We assume that clutch pressure is measured, which is the case in dual clutch transmissions (DCT). The estimation algorithm uses measured rotational speeds and estimated accelerations at the input and output sides of a clutch, measured clutch pressures, and a simplified dynamic model of clutch friction to estimate the viscous and contact components of clutch friction torque. Coefficient of friction data is generated using the contact friction torque. A Stribeck friction model is fit to the data, and parameters in the model are then calculated by applying linear least squares estimation. The proposed estimation algorithm is tested using the simulation of a powertrain utilizing a DCT, where the clutch friction model incorporates a realistic level of fluid film squeeze dynamics. The algorithm is evaluated under ‘noiseless’ and ‘noisy’ conditions. In the ‘noiseless’ case, clutch accelerations and pressure derivatives are obtained by differentiating stored clutch speed and pressure signals. In the ‘noisy’ case, white-Gaussian noise is introduced to the stored signals, with a noise-to-signal amplitude ratio of 10% for speed signals and 5% for pressure signals. The clutch accelerations and pressure derivatives are then estimated using a Kalman filter, and results are presented for both ‘noiseless’ and ‘noisy’ cases. In both cases, friction parameters are estimated within 10% of their respective simulated values, with the estimation accuracy being generally better for the ‘noiseless’ case.
During the last years mechatronic systems developed into one of the biggest drivers of innovation in the automotive industry. The start of production of systems like dual clutch transmission, lane departure warning systems and active suspensions proves this statement. These systems have an influence on the longitudinal, steering and vertical dynamics of the vehicle. That is why the interaction on vehicle level is crucial for an optimal result in the fields of efficiency, comfort, safety and dynamics. To optimize the interaction of mechatronic systems, in this paper a new test rig concept for a complete vehicle is presented. The so-called Car-in-the-Loop-concept is capable of realistically reproducing the loads, which act on the powertrain, the steering and the suspension during a test drive. The resulting advantages are the possibility to exactly reproduce test procedures, the independence from weather conditions and a minimization of the risk of human injuries during testing of safety functions. A prototype of this concept, which includes parts of the powertrain, the steering and the chassis corresponding to the left front side of a BMW Mini Countryman, was built at the lab of the Institute for Mechatronic Systems in Mechanical Engineering of the TU Darmstadt. A test rig shaft connects the wheelhub of the BMW Mini Countryman to actuators, which generate realistic loads corresponding to the current driving situation. To provide the needed adaptiveness for the steering and suspension movement constant velocity joints and ball-spline supported length compensations are included in the test rig shaft. A highly dynamic test drive is being reproduced on the prototype to prove the functionality of the Car-in-the-Loop-concept.
As the number of fixed gear ratios in automatic transmissions continues to increase in the pursuit of powertrain system efficiency, particular consideration must continue to be focused on optimizing the design for shifting performance. This investigation focuses on the effect of shift time on the performance attributes of shift quality, durability, on schedule fuel consumption and enablers to further reduce shift time. A review of fundamental design features that enable reduced shift times in both planetary and dual clutch transmissions is presented along with key operating features of both the transmission and engine/prime mover. A lumped parameter metric is proposed to assess and compare the upshift controllability of new transmission architectures and powerflows using simple analysis. The durability of fast shift times during performance maneuvers are quantified through calculation of shifting clutch energy and power from analysis and form measurements on a powertrain dynamometer. In addition to perceived powertrain performance, powertrain dynamometer measurements running the FTP test schedules fuel consumption trends with respect to inertia phase shift time and can provide upwards of 1.25% by optimization of shift times depending on powertrain details. The paper concludes with vehicle measurements comparing part and wide-open throttle shift times for 6 and 8 speed planetary automatics transmissions.
A direct trajectory optimization approach is developed to assess the capability of a GTDI-DCT Powertrain, with a Gasoline Turbocharged Direct Injection (GTDI) engine and Dual Clutch Transmission (DCT), to satisfy stringent drivability requirements during launch. The optimization is performed directly on a high fidelity black box powertrain model for which a single simulation of a launch event takes about 8 minutes. To address this challenging problem, an efficient parameterization of the control trajectory using Gaussian kernel functions and a Mesh Adaptive Direct Search optimizer are exploited. The results and observations are reported for the case of clutch torque optimization for launch at normal conditions, at high altitude conditions and at non-zero grade conditions. The results and observations are also presented for the case of simultaneous optimization of multiple actuator trajectories at normal conditions.
The 2016 production NSX made its much-awaited global debut at NAIAS in January. More technical details of Acura's mid-engine AWD hybrid supercar will be shared by Honda R&D experts at the SAE 2015 World Congress. Three years removed from its concept-design debut, the Acura NSX supercar took to the 2015 North American International Auto Show (NAIAS) stage once more, this time in its production form. While recognizable as that concept's progeny, the next-generation 2016 NSX revealed this January in Detroit has evolved over its 36-month development program. The Ohio-based, American-led R&D team for the new NSX, with Ted Klaus, Chief Engineer and Global Development Leader, at the helm, has made design and engineering decisions both big and small-but none insignificant-every step of the way.
Items per page:
50
1 – 50 of 111