Four-Wheel Differential Steering Control of IWM Driven EVs

Abstract

This paper aims to realize the four-wheel differential steering function of an in-wheel motor (IWM) driven electric vehicle (EV) with a steer-by-wire (SBW) system. The dynamic models of four-wheel differential steering vehicle (4WDSV) and four-wheel-steering vehicle (4WSV) are established, and a frontwheel-steering vehicle (2WSV) with the neutral steering characteristics and a drop filter of the sideslip angle is employed as the reference model to provide the ideal yaw rate and sideslip angle. According to the reference model, the decoupling and fractional PI  D  controllers are designed for the 4WSV to obtain the standard inputs, i.e., the front and rear wheel steering angles, which is finally drawn as the MAP. Furthermore, the sliding mode controller (SMC) and torque distributor are designed to control the 4WDSV to have the same yaw rate as the 4WSV, whose inputs are consulted from the MAP drawn in advance according to the vehicle speed. The simulation results of several vehicle models with/without the controller of two working conditions (reverse and in phase steering) are presented, which indicates that the proposed decoupling and fractional PI  D  controller for the 4WSV is effective to obtain its standard inputs, and the proposed SMC and torque distributor for the 4WDSV ensure that it has the same yaw rate as the 4WSV, as well as the good robustness. INDEX TERMS Four-wheel differential steering, in-wheel motor driven, decoupling, fractional PI  D  control, sliding model control.

Hierarchical control of differential steering for four-in-wheel-motor electric vehicle

“…Then the sliding mode controller (SMC) and torque distributor were designed to control the four-wheel differential steering vehicle (4WDSV) to have the same yaw rate as the 4WSV. And the simulation results verified the effectiveness of the proposed controllers [27].…”

“…For these multi-actuated electric vehicles, a lot of research have been done, such as the fault-tolerant control [3], the chassis coordinated control [4,5], the integrated vehicle-following control [6][7][8], the energy management strategy [9][10][11], the battery state-of-charge (SOC) estimation [12][13][14], the driving modes [15][16][17], the strength analysis of key components [18,19] and so on. In addition, their appearances also make the differential steering possible, which can be used not only to assist the driver to turn the vehicle [20][21][22][23], but also as a backup system [24][25][26][27][28] and even the only steering system of the vehicle [2,29,30], which can further simplify the structure of the vehicle. Among them, the literatures [2,[25][26][27][28][29][30] are most related to this study.…”

“…In addition, their appearances also make the differential steering possible, which can be used not only to assist the driver to turn the vehicle [20][21][22][23], but also as a backup system [24][25][26][27][28] and even the only steering system of the vehicle [2,29,30], which can further simplify the structure of the vehicle. Among them, the literatures [2,[25][26][27][28][29][30] are most related to this study.…”

Robust fuzzy sliding mode controller for a skid-steered vehicle subjected to friction variations

“…Similarly, the experimental verification of the effectiveness of a fractional order PI controller for a four-wheeled SSV is discussed in [ 27 ]. A fractional order PID controller is reported for generating the standard inputs in a four-wheeled differential drive applications [ 28 ]. Apart from the usual applications of fractional order calculus in control formulations, it is very important to highlight some of its benefits such as robustness to noise and disturbances, wide stability margins and its inherent memory.…”

Studies on Energy Consumption of Electric Light Commercial Vehicle Powered by In-Wheel Drive Modules

“…Despite the unfavorable increase of the unsprung mass of the vehicle, the ability to steer each wheel in various road situations [8,9], as well as the use of electric regenerative braking [10], provide an opportunity to improve the traction properties of the vehicle [11][12][13]. At the same time, the use of a direct drive in the wheel requires the implementation of new technological solutions, such as active suspension [14,15] or a spring system for the electric drive module [16][17][18], the development of various braking algorithms and systems such as anti-lock braking system (ABS), brake assist (BAS), electronic brakeforce distribution (EBD), electronic stability control (ESP) or acceleration slip regulation (ASR), and the use of an electronic differential with the possibility of driving the wheels in the 4 × 2, 4 × 4 system [19]. Motors mounted in the wheels also allow a significant extension of the steering range, giving the vehicle new possibilities in terms of maneuverability.…”