CACC Platoons with imperfect V2V communication
Advisors: Dr. Swaroop Darbha, Dr. Sivakumar Rathinam, Dr. Dileep Kalathil
PhD Thesis Topic
There is a renewed interest in connected and highly automated vehicles, in both academia and industry.
One of the main advantages of automated driving is the ability to improve mobility and safety on highways. Connectivity in vehicles has been demonstrated to safely allow vehicle platooning at short inter vehicular spacing - which would otherwise be unsafe for human drivers.
The minimum allowable (safe) spacing is governed by the actuation lags (especially brake actuation) in the vehicle. Analytical results have been published in the past providing sufficient conditions for platoon stability for Cooperative Adaptive Cruise Control (CACC - one vehicle lookup) control policies. But, these results assume that the Vehicle to Vehicle (V2V) communication link is lossless. But we know from simulations and experiments that if this ideal link assumption is dropped, the performance of the string deteorates and could induce instability in the platoon. One such simulation is shown below. The platoon on the left experiences packet losses while that on the right has perfect communication links. We can see that the lossy platoon on the left is not string stable and experiences multiple rear-end collisions.
We were able to derive sufficient conditions for string stability of CACC platoons operating under lossy V2V links based on the parasitic lags in the braking system of each vehicle.
Please refer to these publications for more details: