TY - JOUR
T1 - New paradigms for the integration of yaw stability and rollover prevention functions in vehicle stability control
AU - Rajamani, Rajesh
AU - Piyabongkarn, Damrongrit Neng
PY - 2013
Y1 - 2013
N2 - The integration of rollover prevention and yaw stability control objectives in electronic stability control (ESC) has traditionally been done based on a priority calculation. The control system nominally focuses on yaw stability control until a danger of rollover is detected. When a danger of rollover is detected, the control system switches from yaw stability control to rollover prevention. This paper focuses on an integrated ESC system wherein the objectives of yaw stability and rollover prevention are addressed simultaneously, rather than one at a time. First, we show that staying on a desired planar trajectory at a specified speed results in an invariant rollover index. This implies that rollover prevention can be achieved whenever there is a danger of rollover only by reducing vehicle speed, since changing the desired vehicle trajectory is not a desirable option. In this regard, it is shown that a vehicle that reduces its speed before entering a sharp curve performs significantly better than a vehicle that uses differential braking during the turn for yaw stability control. Second, this paper explores how the use of steer-by-wire technology can address the tradeoff between yaw stability, speed, and rollover prevention performance. It is shown that the use of traditional steer-by-wire simply as an additional actuator cannot by itself ameliorate the tradeoff. However, this tradeoff can be eliminated if steer-by-wire is used to invert the direction of the roll angle of the vehicle. A new steer-by-wire algorithm that uses transient countersteering is shown to change the location of the rollover dynamics from the neighborhood of an unstable to a stable equilibrium. In this case, a desired trajectory can indeed be achieved by the vehicle at the same speed with a much smaller danger of rollover. This is a novel and viable approach to integrating the yaw stability and rollover prevention functions and eliminating the inherent tradeoffs in the performance of both.
AB - The integration of rollover prevention and yaw stability control objectives in electronic stability control (ESC) has traditionally been done based on a priority calculation. The control system nominally focuses on yaw stability control until a danger of rollover is detected. When a danger of rollover is detected, the control system switches from yaw stability control to rollover prevention. This paper focuses on an integrated ESC system wherein the objectives of yaw stability and rollover prevention are addressed simultaneously, rather than one at a time. First, we show that staying on a desired planar trajectory at a specified speed results in an invariant rollover index. This implies that rollover prevention can be achieved whenever there is a danger of rollover only by reducing vehicle speed, since changing the desired vehicle trajectory is not a desirable option. In this regard, it is shown that a vehicle that reduces its speed before entering a sharp curve performs significantly better than a vehicle that uses differential braking during the turn for yaw stability control. Second, this paper explores how the use of steer-by-wire technology can address the tradeoff between yaw stability, speed, and rollover prevention performance. It is shown that the use of traditional steer-by-wire simply as an additional actuator cannot by itself ameliorate the tradeoff. However, this tradeoff can be eliminated if steer-by-wire is used to invert the direction of the roll angle of the vehicle. A new steer-by-wire algorithm that uses transient countersteering is shown to change the location of the rollover dynamics from the neighborhood of an unstable to a stable equilibrium. In this case, a desired trajectory can indeed be achieved by the vehicle at the same speed with a much smaller danger of rollover. This is a novel and viable approach to integrating the yaw stability and rollover prevention functions and eliminating the inherent tradeoffs in the performance of both.
KW - Electronic stability control
KW - rollover prevention
KW - vehicle dynamics
KW - yaw stability
UR - http://www.scopus.com/inward/record.url?scp=84879298405&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84879298405&partnerID=8YFLogxK
U2 - 10.1109/TITS.2012.2215856
DO - 10.1109/TITS.2012.2215856
M3 - Article
AN - SCOPUS:84879298405
SN - 1524-9050
VL - 14
SP - 249
EP - 261
JO - IEEE Transactions on Intelligent Transportation Systems
JF - IEEE Transactions on Intelligent Transportation Systems
IS - 1
M1 - 6303917
ER -