Browse Topic: Traction control
ABSTRACT In this paper, a conceptually new research direction of the tire slippage analysis is provided as a new technological paradigm for agile tire slippage control. Specifically, the friction coefficient-slippage dynamics is analyzed and its characteristic parameters are introduced. Next, the nonlinear relation between the wheel torque and the tire instantaneous rolling radius incorporating the longitudinal elasticity factor is analyzed. The relation is shown to be related to the tire slippage. Further, its importance is clarified by deriving its dynamics and specifically, the instruction is given how it can be utilized to control slippage. Finally, the indices are introduced to assess the mobility and agility of the wheel in order to achieve optimal response to severe terrain conditions. The indices comprise of the introduced friction coefficient-slippage characteristic parameters. Citation: M. Ghasemi, V. Vantsevich, D. Gorsich, J. Goryca, A. Singh, L. Moradi, “Physics Based
ABSTRACT When building simulation models of military vehicles for mobility analysis over deformable terrain, the powertrain details are often ignored. This is of interest for electric and hybrid-electric vehicles where the maximum torque is produced at low speeds. It is easy to end up with the drive wheels spinning and reducing traction and eventually the vehicle digging itself down in the soil. This paper reveals improvements to mobility results using Traction Control Systems for both wheeled and tracked vehicles. Simulations are performed on hard ground and two types of deformable soil, Lethe sand and snow. For each soft soil, simulations have been performed with a simple terramechanics model (ST) based on Bekker-Wong models and complex terramechanics (CT) using the EDEM discrete element soil model which Pratt & Miller Engineering (PME) has been instrumental in developing. To model the traction control system a PD controller is used that tries to limit the slip velocity at low speed
ABSTRACT A new integrated testing system for the validation of stochastic vehicle-snow interaction models is presented in this paper. The testing system consists of an instrumented test vehicle, vehicle-mounted laser profilometer and a snow micropenetrometer. The test vehicle is equipped on each tire with a set of 6-axis wheel transducers, and a GPS-based data logger tracks vehicle motion. Data is also simultaneously acquired from the sensors from the test vehicle’s Electronic Stability Program. The test vehicle provides measurements that include three forces and moments at each wheel center, vehicle body slip angle, speed, acceleration, yaw rate, roll, and pitch. The profilometer has a 3-D scanning laser and an Inertial Measurement Unit to compensate for vehicle motion. Depth of snow cover, profile of snow surface and wheel sinkage can be obtained from the profilometer. The snow micropenetrometer measures the strength of the snow cover before and after vehicle traversal. Preliminary
The purpose of this SAE Information Report is to describe currently known automotive active stability enhancement systems, as well as identify common names which can be used to refer to the various systems and common features and functions of the various systems. The primary systems discussed are: a ABS - Antilock Brake Systems b TCS - Traction Control Systems c ESC - Electronic Stability Control The document is technical in nature and attempts to remain neutral regarding unique features that individual system or vehicle manufacturers may provide
This SAE Recommended Practice identifies and defines terms specifically related to truck and bus braking systems including Antilock Brake Systems (ABS) and Electronically Controlled Braking Systems (ECBS
The current simulation models of EV and ICE Vehicles are well known in industry for their use in estimating the fuel economy or Range benefits because of controller calibrations and component sizing. However, there is a gap in understanding the behavior of accessories such as HVAC, power steering and other such auxiliary loads and the energy losses associated with them. Impact of thermal behavior of electronics on vehicle range also needs to be studied in detail. These kinds of studies help OEM and tier 1 manufactures in improving their design concepts significantly with minimum cost and development time. Hence, the focus of this study is on building simulation models of thermal, electrical, traction and control circuits of a typical electric vehicle. These models are then integrated, and analysis is performed to understand vehicle system level performance metrics. Individual models have been built for HVAC and thermal circuit of on EV in AMESim, HV and LV electrical power distribution
This SAE Recommended Practice establishes uniform procedures for testing battery electric vehicles (BEVs) which are capable of being operated on public and private roads. The procedure applies only to vehicles using batteries as their sole source of power. It is the intent of this document to provide standard tests which will allow for the determination of energy consumption and range for light-duty vehicles (LDVs) based on the federal emission test procedure (FTP) using the urban dynamometer driving schedule (UDDS) and the highway fuel economy driving schedule (HFEDS) and provide a flexible testing methodology that is capable of accommodating additional test cycles as needed. Additionally, this SAE Recommended Practice provides five-cycle testing guidelines for vehicles performing supplementary testing on the US06, SC03, and cold FTP procedure. Realistic alternatives should be allowed for new technology. Evaluations are based on the total vehicle system’s performance and not on
A TCS strategy of electric vehicle with 4 in-wheel motors is proposed in this paper. The control method consists of three parts: target slip rate calculation, target torque calculation and coordination control. By using Lyapunov stability analysis algorithm, the target slip rate boundary which makes the system stable is obtained. The target torque of each wheel is calculated by PI controller. According to the engineering experience, the TCS coordinated control strategy under split friction coefficient (split-μ) road, and friction coefficient jump(μ jump) road is proposed. The test results show that this strategy can improve the acceleration comfort and yaw stability of vehicles on uniform low friction coefficient (low μ) , split-μ and μ jump road
As the world searches for ways to reduce humanity’s impact on the environment, the automotive industry looks to extend the viable use of the gasoline engine by improving efficiency. One way to improve engine efficiency is through more effective control. Torque-based control is critical in modern cars and trucks for traction control, stability control, advanced driver assistance systems, and autonomous vehicle systems. Closed loop torque-based engine control systems require feedback signal(s); indicated mean effective pressure (IMEP) is a useful signal but is costly to measure directly with in-cylinder pressure sensors. Previous work has been done in torque and IMEP estimation using crankshaft acceleration and ion sensors, but these systems lack accuracy in some operating ranges and the ability to estimate cycle-cycle variation. In this study, we show that a data driven system to estimate IMEP using frequency content of crank acceleration, exhaust pressure, and ion current with
This SAE Recommended Practice establishes uniform test procedures for air brake systems pneumatic, electronic, and electrical/pneumatic valves with respect to: a Input-output performance b Leakage characteristics c Low temperature evaluation d Elevated temperature evaluation e Corrosion resistance evaluation f Endurance testing g Structural integrity h Vibration testing
This document is written to address acceleration and deceleration control issues related to heavy-duty trucks and buses greater than 10000 GVW
This document is not a standard, it is a candidate for a standard being submitted to SAE for their consideration as a comment to SAE J2735. The term SAE J2735 SE candidate is used within this document to refer to this submission. This document specifies dialogs, messages, and the data frames and data elements that make up the messages specifically for use by applications intended to utilize the 5.9 GHz Dedicated Short Range Communications for Wireless Access in Vehicular Environments (DSRC/WAVE, referenced in this document simply as “DSRC"), communications systems. Although the scope of this Standard is focused on DSRC, these dialogs, messages, data frames and data elements have been designed, to the extent possible, to be of use for applications that may be deployed in conjunction with other wireless communications technologies. This standard therefore specifies the definitive message structure and provides sufficient background information to allow readers to properly interpret the
A Direct Yaw-Moment Control (DYC) logic for a rear-wheel-drive electric-powered vehicle is proposed. The vehicle is a Formula SAE (FSAE) type race car, with two electric motors powering each rear wheel. Vehicle baseline balance is neutral at low speeds, for increased maneuverability, and increases understeering at high speeds (due to the aerodynamic configuration) for stability. A controller that can deal with these yaw response variations, modelling uncertainties, and vehicle nonlinear behavior at limit handling is proposed. A two-level control strategy is considered. For the upper level, yaw rate and sideslip angle are considered as feedback control variables and a cubic-error Proportional Derivative (PD) controller is proposed for the feedback control. For the lower level, a traction control algorithm is used, together with the yaw moment requirement, for torque allocation. Performance of the controller was evaluated using the Sine with Dwell maneuver and also a lap time simulation
Wheel slip control is crucial to active safety control systems such as Traction Control System (TCS) and Anti-lock Braking System (ABS) that ensure vehicle safety by maintaining the wheel slip in a stable region. For this reason, a wide variety of control methods has been implemented by both researchers and in the industry. Moreover, the use of new electro-hydraulic or electro-mechanical brakes, and in-wheel electric motors allow for a more precise wheel slip control, which should further improve the vehicle dynamics and safety. In this paper, we compare two methods for wheel slip control: a loop-shaping Youla parametrization method, and a sliding mode control method. Each controller is designed based on a simple single wheel system. The benefits and drawbacks of both methods are addressed. Finally, the performance and stability robustness of each controller is evaluated based on several metrics in a simulation using a high-fidelity vehicle model with several driving scenarios
Separate from the event data recorder (EDR), which records and stores data from qualifying vehicle crash events, the Vehicle Control History (VCH) on Toyota vehicles records and stores certain vehicle data based on select driver inputs, such as hard acceleration or braking, or upon the activation of certain vehicle dynamic control systems such as antilock braking system (ABS), traction control (TRAC), vehicle stability control (VSC), and the pre-collision system (PCS). In the United States, VCH was first equipped on the 2013 Toyota RAV4 and has been subsequently introduced into other Toyota and Lexus models. Most recently, in addition to VCH data, additional PCS operational data (PCS-O) and image data (PCS-I) may be recorded and stored. The image storage capability may record under certain conditions such as if the system has automatically applied the vehicle brakes. PCS-O and PCS-I data became available with the launch of Toyota Safety Sense (TSS), a grouping of advanced active safety
Today’s vehicles rely on multiple interconnected networks of Electronic Control Units (ECUs) that govern almost every automotive function - from engine timing and traction control to side-mirror adjustment and GPS. In-vehicle networks used for inter-ECU communication, most commonly the CAN bus, were not designed with cybersecurity in mind, and as a result, communication by corrupt devices connected to the bus is not authenticated. A multitude of attack vectors allow attackers to control a device on the bus; reports abound of successful hacking of vehicles, by exploiting vulnerable devices and by spoofing messages. Such remote-connectivity and physical-access exploit types must be prevented, to mitigate the threats of impersonation, eavesdropping, replay and reversing. We present the IVAS, In-Vehicle Authentication Scheme. IVAS is an in-place cryptographic scheme: the first CAN messaging solution to ensure both authentication and confidentiality without additional data such as
This SAE document defines a recommended practice for implementing circuit identification for electrical power and signal distribution systems of the Class 8 trucks and tractors. This document provides a description of a supplemental circuit identifier that shall be utilized in conjunction with the original equipment manufacturer’s primary circuit identification as used in wire harnesses but does not include electrical or electronic devices which have pigtails. The supplemental circuit identifier is cross-referenced to a specified subsystem of the power and signal distribution system identified in Section 5
In this SAE Recommended Practice, attention will be given to passenger cars and light trucks (through Class III
Electronic control units (ECU) from Kawasaki Ninja ZX-6R and ZX-10R motorcycles were tested in order to examine the capabilities and behavior of the event data recorders (EDR). All relevant hexadecimal data was downloaded from the ECU and translated using known and historically proven applications. The hexadecimal translations were then confirmed using data acquisition systems as well as the Kawasaki Diagnostic Software (KDS)1. Numerous tests were performed to establish the algorithms which cause the EDR to record data. Issues of sensor and power loss were analyzed and discussed. Additionally, data sets were studied that involved maximum deceleration from ABS brakes. Similarly, data sets that involved traction control intervention were studied and analyzed. It was determined that the EDR recording ‘trigger’ was caused by the activation of the tip-over sensor, which in turn shuts the engine off. However, specific conditions must be met with regards to the rear wheel rotation prior to
The purpose of this SAE Information Report is to describe currently known automotive active stability enhancement systems, as well as identify common names which can be used to refer to the various systems and common features and functions of the various systems. The primary systems discussed are: a ABS - Antilock Brake Systems b TCS - Traction Control Systems c ESC - Electronic Stability Control The document is technical in nature and attempts to remain neutral regarding unique features that individual system or vehicle manufacturers may provide
In recent times, electric vehicles (EV) are gaining a lot of attention as they run clean and are environment friendly. Recent advances in the applications of integrating control systems in automotive vehicles have made it practicable to accomplish improvement in vehicle's longitudinal and lateral dynamics. This paper deals with a brief overview of current state of art vehicle technologies like direct yaw moment control, traction control and side slip control of EV. There are various controller algorithms available in literature with different torque vectoring strategies. As EV can be precisely controlled because of quick in hub wheel motor response times, therefore various torque vectoring strategies can be comfortably used for enhancing vehicle dynamics. Moreover, by using four independent in-wheel motors, several types of motion controls can be performed. These motion controls are intensively researched by a comprehensive literature review with an aim to obtain desired vehicle
This document supersedes SAE J2012 DEC2007, and is technically equivalent to ISO 15031-6:2010 with the exceptions described in 1.2. This document is intended to define the standardized Diagnostic Trouble Codes (DTC) that On-Board Diagnostic (OBD) systems in vehicles are required to report when malfunctions are detected. SAE J2012 may also be used for decoding of enhanced diagnostic DTCs and specifies the ranges reserved for vehicle manufacturer specific usage. This document includes: a Diagnostic Trouble Code format. b A description of the standardized set of Diagnostic Trouble Codes and descriptions contained in SAE J2012DA. The two most significant bytes of a DTC may be decoded according to two different lists; DTC Format Identifier 0x00 and 0x04. c A description of the standardized set of Diagnostic Trouble Codes subtypes known as Failure Types contained in SAE J2012-DA (applies only when three byte DTCs are used
Vehicle dynamics control (VDC) for motorcycles had a fast growth during the last 10 years. The available technologies comprise curve-safe ABS and traction control (TC) systems, anti-wheelie control, right up to comprehensive motorcycle stability systems including even more control functions. VDC systems rely on real-time information about the current motorcycle dynamic state. Thus motorcycles are equipped with additional sensor units, namely MEMS inertial measurement devices, capable of gathering accelerations and angular rates. The application of model-based estimation theory enables the determination of the necessary information about the in-plane and out-of-plane motion, e.g. the motorcycle lean angle. Since VDC systems include safety critical control functions, the validation within simulations including sensor characteristics is mandatory. The MEMS accelerometer and gyroscope features include low-cost and small footprint, however there are considerable stochastic sensor errors to
Since the introduction of electronically controlled air suspension (ECAS) systems in the nineties, no major improvements have been made in the realm of controlling air suspensions in the heavy duty truck market. Despite the lack of improvement, a need exists for intelligently controlled air suspension systems, specifically systems which can be applied to 6x2 axle configurations in the North American market. This study outlines a concept proposal for a novel suspension control concept which encompasses traction control capabilities in addition to suspension control for improved fuel efficiency benefit. The major novelty of the concept is that, by utilizing specific axle configurations and tires, a shift in pressure from the driven to the non-driven axles may result in improvements in the overall fuel economy of the vehicle. The shift in pressure will allow ride height to be maintained while increasing fuel economy benefits if the tires used on the non-driven axles have lower rolling
This SAE Recommended Practice establishes uniform test procedures for air brake systems pneumatic valves with respect to: a Input-Output Performance b Leakage Characteristics c Low Temperature Evaluation d Elevated Temperature Evaluation e Corrosion Resistance Evaluation f Endurance Testing g Structural Integrity h Vibration Testing
A program of integrated electro-hydraulic braking system is proposed, and its structural composition and working principle are analyzed. According to the structural and mechanical characteristics of all key components, through some reasonable assumptions and simplifications, a motor, a brake master cylinder, four brake wheel cylinders, solenoid valves and an ESP (Electronic Stability Program) algorithm model is set up and simulations of typical braking conditions are carried out based on the Matlab/Simulink. Finally, after the assembly of each sub-model is complete and combining a vehicle which is set up in CarSim software environment, simulation tests and comprehensive performance analysis of the active safety stability control for a vehicle in double lane change and single lane change situations are carried out respectively. According to the dynamic characteristic curves of system, the effects of different structural and control parameters on braking performance are analyzed. To
Developments of new Electric and Hybrid propulsion systems demands chassis adaptations. The purpose of the XeV project was to develop and integrate a full suite of active chassis systems to deliver a fully electrified All-Wheel-Drive Pick-up truck. To achieve so, a new chassis frame, engine cradles and battery box were designed to bring direct drive from electric motor to wheel. On the other hand, for a four-wheelindependent-drive, a new rear suspension design was implemented, and a complex torque vectoring and traction control strategy was developed to provide optimum on and off road performance. All systems were tuned to meet the new drivetrain configuration, weight distribution and vehicle loading conditions making it possible to achieve comparable results with respect to the original combustion engine vehicle
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