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A Heavy Tractor Semi-Trailer Stability Control Strategy Based on Electronic Pneumatic Braking System HIL Test

SAE International Journal of Vehicle Dynamics, Stability, and NVH

State Key Laboratory of Automotive Simulation and Control, Jilin University, China-Hongyu Zheng, Yangyang Miao
United States-Bin Li
  • Journal Article
  • 10-03-03-0016
Published 2019-10-15 by SAE International in United States
Aiming to improve the handling performance of heavy tractor semi-trailer during turning or changing lanes at high speed, a hierarchical structure controller is proposed and a hardware-in-the-loop (HIL) test bench of the electronic pneumatic braking system is developed to validate the proposed controller. In the upper controller, a Kalman filter observer based on the heavy tractor semi-trailer dynamic model is used to estimate the yaw rates and sideslip angles of the tractor and trailer. Simultaneously, a sliding mode direct yaw moment controller is developed, which takes the estimated yaw rates and sideslip angles and the reference values calculated by the three-degrees-of-freedom dynamic model of the heavy tractor semi-trailer as the control inputs. In the lower controller, the additional yaw moments of tractor and trailer are transformed into corresponding wheel braking forces according to the current steering characteristics. The HIL test bench of the electronic pneumatic braking system is built to verify the effectiveness of the strategy. Double lane-change maneuver, sinusoidal maneuver, and J-turn maneuver are selected as handling and stability test conditions. The LabView real-time…
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Fuel Efficiency Improvement in Automatic Transmissions by Lockup Slip Methodology

Mahindra & Mahindra, Ltd.-Arun Sukumar
Published 2019-10-11 by SAE International in United States
Increasing of automatic transmissions in passenger cars is based on pleasure of driving, smooth acceleration and easy operation makes the customer satisfaction. Challenges beyond 2020 is BS VI emission norms in India - a very tough goals on CO2& NOx reduction in Gasoline & Diesel vehicles. But its setback in lower fuel economy.To support & enhance fuel economy in Automatic transmissions as part of drivetrain technologies, this article discusses about the power losses in torque converters and experiments on the actual Automatic transmission (AT) vehicle on-road to understand the real city driving behavior in the aspects of gear utilization & gas pedal utilization throughout the entire traffic conditions. With that data research, slip area and slipping conditions is determined & clutch slip control is enabled at area in torque converter by ensuring that NVH parameters are not affected.The addition of the Lock-up Slip system add value in terms of “Joy of Driving” by providing a 2-3% improvement in fuel economy over the previous one.
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Modelling and Validation of a Control Algorithm for Yaw Stability & Body Slip Control Using PID & Fuzzy Logic Based Controllers

SITAMS-Chellappan Kavitha
VIT University-Umashankar Lath, Sanyam Kakkar, Aman Agarwal, Bragadeshwaran Ashok, Vemuluri Ramesh Babu, Sathiaseelan Denis Ashok
Published 2019-10-11 by SAE International in United States
Advanced driver-assistance systems (ADAS) are becoming an essential part of the modern commercial automobile industry. Vehicle handling and stability are determined by the yaw rate and body slip of the vehicle. This paper is a comparative study of a nonlinear vehicle stability control algorithms for steering control based on two different controllers i.e. fuzzy logic based controller and PID controller. A full vehicle 14DOF model was made in Simulink to simulate an actual vehicle. The control algorithms are based on a two-track 7-DOF model with a non-linear tire model based on Pacejka “Magic tire formula”, which was used to establish the desired response of a full vehicle 14DOF model. It was found that the fuzzy logic-based control algorithm demonstrated an overall superior performance characteristic than a PID based control algorithm; this includes a significant decrease in time lag and overshoot. The proposed control algorithms were validated through the co-simulation of Carsim and Simulink in real time.
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Ford revisits OHV layout, big displacement for new commercial-truck V8

SAE Truck & Off-Highway Engineering: October 2019

Bill Visnic
  • Magazine Article
  • 19TOFHP10_09
Published 2019-10-01 by SAE International in United States

In a still-heated market for highly profitable heavy-duty pickups and commercial vehicles, Ford doesn't intend to be outdone by General Motors' and FiatChrysler's recently-launched new efforts, announcing the power and torque figures for its all-new 7.3-L gasoline V8 for its 2020 models and reminding that major revisions for 2020 for its Power Stroke diesel V8 also portend to increased power.

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Ford returns to OHV for new commercial-truck V8

Automotive Engineering: September 2019

Bill Visnic
  • Magazine Article
  • 19AUTP09_14
Published 2019-09-01 by SAE International in United States

In a still-heated market for highly profitable heavy-duty pickups and commercial vehicles, Ford doesn't intend to be outdone by General Motors' and FiatChrysler's recently-launched new lineups. It announced the SAE-certified power and torque figures for its all-new 7.3-L gasoline V8 for its 2020 models, while reminding that major revisions for its 2020 Power Stroke diesel V8 also portend to increased power.

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A Novel Heating-Coating Hybrid Strategy for Wind Turbine Icing Mitigation

Iowa State University-Linyue Gao, Liqun Ma, Yang Liu, Hui Hu
Published 2019-06-10 by SAE International in United States
The electro-thermal method is most commonly used for wind turbine anti-/de-icing. The upmost drawback of such systems is the high power consumption. In the present study, we proposed to use a durable slippery liquid-infused porous surface (SLIPS) to effectively reduce the power requirement of the heating element during the anti-/de-icing process. The explorative study was conducted in the Icing Research Tunnel at Iowa State University (ISU-IRT) with a DU91-W2-250 wind turbine blade model exposed under severe icing conditions. During the experiments, while a high-speed imaging system was used to record the dynamic ice accretion process, an infrared (IR) thermal imaging system was also utilized to achieve the simultaneous surface temperature measurements over the test model. In comparison to the traditional electrical heating strategies to brutally heat massive area of entire turbine blades, a novel heating-coating hybrid strategy, i.e., combining a leading-edge (LE) heating element to cover the first 30% of the chord length (C) along with using SLIPS to coat entire blade surface, was found to be able to keep the entire blade surface completely…
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An Experimental Investigation of a Wind-Driven Water Droplet over the Slippery Liquid Infused Porous Surface

Iowa State University-Liqun Ma, Hui Hu
Published 2019-06-10 by SAE International in United States
The promising anti-icing performance of the slippery liquid infused porous surface (SLIPS) has been recently demonstrated for various engineering applications. The runback icing for aircraft and wind turbines could be effectively mitigated considering the timely removal of water droplet by the wind shearing force due to the low adhesion on the SLIPS. In this study, the flow field both inside and around the wind-driven droplet over the SLIPS was experimentally investigated by using Particle Image Velocimetry (PIV) technique. Previous studies majorly focus on the internal flow pattern before the droplet incipient motion. In this study, the flow field inside a moving droplet was firstly investigated. As a result of the low surface adhesion of the SLIPS, droplet oscillations were eliminated and the droplet internal flow field could be corrected from the optical distortion. Besides the discussion on the wind speed, the droplet viscosity was also studied by varying the water concentration of the glycerin-water solution. It was found that the internal circulation was highly related with the droplet viscosity. The inner circulations within the water…
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An Experimental Study to Evaluate the Droplet Impinging Erosion Characteristics of an Icephobic, Elastic Soft Surface

Iowa State University-Liqun Ma, Zichen Zhang, Yang Liu, Hui Hu
Published 2019-06-10 by SAE International in United States
Elastic soft material/surface, such as Polydimethylsiloxane (PDMS), is a perspective, useful and low-cost hydrophobic and icephobic coating. While it has been reported to have good mechanical durability, its erosion durability under the high impacting of water droplets pertinent to aircraft inflight icing phenomena has not been explored. In this study, the droplet imping erosion characteristics of an icephobic PDMS surface/material is evaluated systematically upon the dynamic impinging of water droplets at different impact velocities (~ up to 75m/s), in comparison with other state-of-the-art icephobic materials/surfaces, such as superhydrophobic surface (SHS) and slippery liquid-infused porous surface (SLIPS). Surprisingly, the contact angle (CA) of the elastic PDMS is shown to have an over 20° increase (from 105° to 128°), which represents better hydrophobicity, after the erosion test which is mainly contributed to the higher roughness of the eroded PDMS surface. As for the icephobicity evaluation, intact PDMS was found to has ultra-low ice adhesion (~8 kPa), in comparison with SHS (i.e., ~100kPa) and SLIPS (i.e., ~35kPa). PDMS also shows outstandingly stable ice adhesion during the erosion test…
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Understanding the Stick Slip Behavior of Plastics and Target Setting: An OEM Perspective

Mahindra & Mahindra, Ltd.-Sundaralingam Somasundharam, Amit Kumar, Riyazuddin Mohammed, Prasath Raghavendran
Published 2019-06-05 by SAE International in United States
Automotive OEMs are aggressively using different materials for interiors due to value proposition and variety of options available for customers in market. Excessive usage of different grade plastics with zero gap philosophy can cause stick slip effect leading to squeak noise. Even though systems and subsystems are designed using best practices of structural design and manufacturing tolerances, extreme environmental conditions can induce contacts leading to squeak noise. Appropriate selection of interface material pairs can minimize the possibilities of squeak conditions. Stick-slip behavior of different plastics is discussed in the present study, along with critical parameters during material compatibility testing in a tribological test stand. Friction coefficient of different material pairs for a defined normal load and sliding velocity are analyzed for patterns to recognize squeaks versus time. An OEM perspective is presented with focus on material selection using objective metrics like coefficient of friction and set targets for raw material suppliers regarding compatible materials. In the next step, an algorithm based on machine learning approach has been developed for estimating stick-slip performance.
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Distributed Drive Electric Vehicle Longitudinal Velocity Estimation with Adaptive Kalman Filter: Theory and Experiment

China Automotive Engineering Research Institute Co., Ltd.-Yaming Zhang
Tongji University-Bo Leng, Lu Xiong, Zhuoping Yu, Dequan Zeng
Published 2019-04-02 by SAE International in United States
Velocity is one of the most important inputs of active safety systems such as ABS, TCS, ESC, ACC, AEB et al. In a distributed drive electric vehicle equipped with four in-wheel motors, velocity is hard to obtain due to all-wheel drive, especially in wheel slipping conditions. This paper focus on longitudinal velocity estimation of the distributed drive electric vehicle. Firstly, a basic longitudinal velocity estimation method is built based on a typical Kalman filter, where four wheel speeds obtained by wheel speed sensors constitute an observation variable and the longitudinal acceleration measured by an inertia moment unit is chosen as input variable. In simulations, the typical Kalman filter show good results when no wheel slips; when one or more wheels slip, the typical Kalman filter with constant covariance matrices does not work well. Therefore, a gain matrix adjusting Kalman filter which can detect the wheel slip and cope with that is proposed. Simulations are carried out in different conditions, including no wheel slips, one wheel slips, all wheel slip, passing a bump, and variable acceleration…
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