Equilibrium Analysis of Drifting Vehicles for Control Design

2009 ◽  
Author(s):  
Rami Y. Hindiyeh ◽  
J. Christian Gerdes
Keyword(s):  
Saddle Points ◽  
Operating Regime ◽  
Longitudinal Force ◽  
Rear Wheel ◽  
Equilibrium Analysis ◽  
Bicycle Model ◽  
Wheel Drive ◽  
Force Coupling ◽  
Low Sensitivity ◽  
Insight Into

This paper presents an analysis of the dynamics of a rear wheel drive vehicle during cornering at high sideslip angles (“drifting”) using a three-state bicycle model. This model builds upon previous work with a two-state bicycle model by incorporating longitudinal dynamics and a nonlinear tire model with simplified lateral-longitudinal force coupling. Analysis of this model reveals the existence of unstable “drift equilibria” corresponding to steady state cornering at high sideslip angles with significant longitudinal force applied at the rear tire. These equilibria are saddle points, with characteristics that exhibit low sensitivity to friction and speed variation. The analysis of the equilibria provides insight into vehicle dynamics in an operating regime responsible for major safety concerns in everyday driving. It also sheds light upon aspects of the system dynamics that account for behavior observed in autonomous drift experiments and must be considered in future controller designs.

scholarly journals Terrestrial force production by the limbs of a semi-aquatic salamander provides insight into the evolution of terrestrial locomotor mechanics

2021 ◽  
Author(s):  
Sandy Momoe Kawano ◽  
Richard W. Blob
Keyword(s):  
Adult Life ◽  
Force Production ◽  
Rear Wheel ◽  
Ambystoma Tigrinum ◽  
Terrestrial Locomotion ◽  
Hind Limbs ◽  
Wheel Drive ◽  
Reaction Forces ◽  
Pleurodeles Waltl ◽  
Insight Into

Amphibious fishes and salamanders are valuable functional analogs for vertebrates that spanned the water-to-land transition. However, investigations of walking mechanics have focused on terrestrial salamanders and, thus, may better reflect the capabilities of stem tetrapods that were already terrestrial. The earliest tetrapods were aquatic, so salamanders that are not primarily terrestrial may yield more appropriate data for modelling the incipient stages of terrestrial locomotion. In the present study, locomotor biomechanics were quantified from semi-aquatic Pleurodeles waltl, a salamander that spends most of its adult life in water, and then compared to a primarily terrestrial salamander (Ambystoma tigrinum) and semi-aquatic fish (Periophthalmus barbarus) to evaluate whether walking mechanics show greater similarity between species with ecological versus phylogenetic similarities. Ground reaction forces (GRFs) from individual limbs or fins indicated that the pectoral appendages of each taxon had distinct patterns of force production, but hind limb forces were comparable between the salamanders. The rate of force development ('yank') was sometimes slower in P. waltl but generally comparable between the three species. Finally, medial inclination of the GRF in P. waltl was intermediate between semi-aquatic fish and terrestrial salamanders, potentially elevating bone stresses among more aquatic taxa as they move on land. These data provide a framework for modelling stem tetrapods using an earlier stage of quadrupedal locomotion that was powered primarily by the hind limbs (i.e., "rear-wheel drive"), and reveal mechanisms for appendages to generate propulsion in three locomotor strategies that are presumed to have occurred across the water-to-land transition in vertebrate evolution.

Insight into the thermostability and low sensitivity of energetic salts based on planar fused-triazole cation

Polyhedron ◽  
2021 ◽  
Vol 201 ◽  
pp. 115158
Author(s):  
Chengming Bian ◽  
Qunying Lei ◽  
Ji Zhang ◽  
Xiang Guo ◽  
Zhinan Ma ◽  
...  
Keyword(s):  
Energetic Salts ◽  
Low Sensitivity ◽  
Insight Into

Development of the Control Strategy for an Innovative 4WD Device

2006 ◽  
Author(s):  
Federico Cheli ◽  
Paolo Dellacha` ◽  
Andrea Zorzutti
Keyword(s):  
Automotive Industry ◽  
Controller Design ◽  
Rear Wheel ◽  
Front Axle ◽  
Torque Distribution ◽  
Actuation System ◽  
Wheel Drive ◽  
Wet Clutch ◽  
The One ◽  
Engine Crankshaft

The potentialities shown by controlled differentials are making the automotive industry to explore this field. While VDC systems can only guarantee a safe behaviour at limit, a controlled differential can also increase the handling performance. The system derives from a rear wheel drive architecture with a semi-active differential, to which has been added a controlled wet clutch that directly connects the front axle and the engine crankshaft. This device allows distributing the drive torque between the two axles, according to the constraints due to kinematics and thermal problems. It can be easily understood that in this device the torque distribution doesn’t depend only from the central clutch action, but also from the engaged gear. Because of that the central clutch controller has to consider the gear position too. The control algorithms development was carried on using a vehicle model which can precisely simulate the handling response, the powertrain dynamic and the actuation system behaviour. A right powertrain response required the development of a customize library in Simulink. The approach chosen to carry on this research was the one used in automotive industry nowadays: an intensive simulation campaign was executed to realize an initial controller design and tuning.

Modeling and Controlling of Anti-Slip Regulation Based on Limited-Slip Differential

2011 ◽  
Vol 86 ◽  
pp. 762-766
Author(s):  
Jian Jun Hu ◽  
Peng Ge ◽  
Zheng Bin He ◽  
Da Tong Qin
Keyword(s):  
Dynamic Models ◽  
Fuzzy Controller ◽  
Rear Wheel ◽  
Pi Controller ◽  
Hydraulic Control ◽  
Electronic Throttle ◽  
Adhesion Coefficient ◽  
The Road ◽  
Wheel Drive ◽  
Hydraulic Control System

The dynamic models of whole rear-wheel drive vehicle, limited-slip differential, hydraulic control system and electronic throttle were established. Simulations of acceleration course on split-µ road, checkerboard-µ road, low-µ road and step-µ road were carried out combining electronic throttle PI controller and limited-slip differential fuzzy controller. The results show that the Anti-slip Regulation quickly works according to the road adhesion coefficient, effectively inhibits the slip of driving wheels on low adhesion coefficient road, the acceleration performance driving on bad roads was improved obviously, and show a good adaptability.

scholarly journals Vehicle Sideslip Angle Estimation Based on Tire Model Adaptation

Electronics ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 199 ◽  
Author(s):  
Kanwar Bharat Singh
Keyword(s):  
Experimental Tests ◽  
Estimation Algorithm ◽  
Rear Wheel ◽  
Stability Control ◽  
Operating Conditions ◽  
Successful Implementation ◽  
Tire Model ◽  
Sideslip Angle ◽  
Wheel Drive ◽  
Sideslip Estimation

Information about the vehicle sideslip angle is crucial for the successful implementation of advanced stability control systems. In production vehicles, sideslip angle is difficult to measure within the desired accuracy level because of high costs and other associated impracticalities. This paper presents a novel framework for estimation of the vehicle sideslip angle. The proposed algorithm utilizes an adaptive tire model in conjunction with a model-based observer. The proposed adaptive tire model is capable of coping with changes to the tire operating conditions. More specifically, extensions have been made to Pacejka's Magic Formula expressions for the tire cornering stiffness and peak grip level. These model extensions account for variations in the tire inflation pressure, load, tread depth and temperature. The vehicle sideslip estimation algorithm is evaluated through experimental tests done on a rear wheel drive (RWD) vehicle. Detailed experimental results show that the developed system can reliably estimate the vehicle sideslip angle during both steady state and transient maneuvers.

scholarly journals Geometric performance parameters of three-point hitch linkage system of a 2WD Indian tractor

2016 ◽  
Vol 61 (No. 1) ◽  
pp. 47-53 ◽  
Author(s):  
G.V. Kumar Prasanna
Keyword(s):  
Linkage Analysis ◽  
Rear Axle ◽  
Performance Parameters ◽  
Effective Utilization ◽  
Pivot Point ◽  
Wheel Drive ◽  
Weight Transfer ◽  
Insight Into

Geometric performance parameters of three-point hitch system of a most sold model of a 2-wheel drive Indian tractor were determined by generating the path of upper and lower hitch points by kinematic linkage analysis. At various locations of pivot point of upper link and adjustments in the length of lift rods, hitch linkage system of the tractor fulfilled all the requirements specified by the standards for category-I and II hitches. An insight into the kinematic linkage analysis revealed that the hitch linkage of the selected tractor is the most suitable for operations with soil working implements. Attachment of upper link to the topmost pivot point reduced the change in orientation of implement during lifting and ensured better weight transfer from implement to the rear axle of tractor. The kinematic linkage analysis has the potential to identify the best settings of the hitch linkage system for the effective utilization of tractor power during various farm operations.

Collaborative control of a dual electro-hydraulic regenerative brake system for a rear-wheel-drive electric vehicle

2018 ◽  
Vol 233 (4) ◽  
pp. 1035-1046 ◽  
Author(s):  
Jonathan Nadeau ◽  
Philippe Micheau ◽  
Maxime Boisvert
Keyword(s):  
Electric Vehicle ◽  
Energy Recovery ◽  
Rear Wheel ◽  
Brake System ◽  
Force Distribution ◽  
Hydraulic Brake ◽  
Brake Pressure ◽  
Wheel Drive ◽  
Brake Force ◽  
Brake Force Distribution

Within the field of electric vehicles, the cooperative control of a dual electro-hydraulic regenerative brake system using the foot brake pedal as the sole input of driver brake requests is a challenging control problem, especially when the electro-hydraulic brake system features on/off solenoid valves which are widely used in the automotive industry. This type of hydraulic actuator is hard to use to perform a fine brake pressure regulation. Thus, this paper focuses on the implementation of a novel controller design for a dual electro-hydraulic regenerative brake system featuring on/off solenoid valves which track an “ideal” brake force distribution. As an improvement to a standard brake force distribution, it can provide the reach of the maximum braking adherence and can improve the energy recovery of a rear-wheel-drive electric vehicle. This improvement in energy recovery is possible with the complete substitution of the rear hydraulic brake force with a regenerative brake force until the reach of the electric powertrain constraints. It is done by performing a proper brake pressure fine regulation through the proposed variable structure control of the on/off solenoid valves provided by the hydraulic platform of the vehicle stability system. Through road tests, the tracking feasibility of the proposed brake force distribution with the mechatronic system developed is validated.

Conceptual Designs of Strong Hybrid Vehicle Powertrains

2004 ◽  
Author(s):  
Gene Y. Liao ◽  
Trudy R. Weber ◽  
Shawn D. Sarbacker ◽  
Donald P. Pfaff
Keyword(s):  
Energy Recovery ◽  
Torque Converter ◽  
Hybrid Vehicle ◽  
Rear Wheel ◽  
Front Axle ◽  
Wheel Drive ◽  
Hybrid Powertrains ◽  
Conceptual Designs ◽  
Variable Transmission ◽  
Braking Energy Recovery

This paper describes four conceptual designs of strong hybrid vehicle powertrains. These concepts enable conversion of conventional powertrains into strong hybrid powertrains with minimal tear-up to the existing architecture. These concepts are configured as follows: (1) incorporates an electric machine attached to the front axle of a conventional rear-wheel-drive vehicle; (2) a Flywheel-Alternator-Starter (FAS) system with a motor placed between the torque converter and the transmission; (3) same as previous one but where the torque converter is replaced by a starting clutch; and (4) a dual mode Electric Variable Transmission (EVT). These concepts provide extensive hybrid functionality such as, electric motor-only drive; launch assist, braking energy recovery and regeneration. Simulation results indicate that the proposed strong hybrid concepts have the potential to provide fuel economy gains of 19% to 26% over conventional powertrains.

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