This paper consists of two components. The First component addresses a key AHS infrastructure support issue—providing eight extra connector ramps, in addition to the eight existing highway-to-highway connector ramps for the conventional manual traffic, at a highway-to-highway interchange for accommodating continuous automated driving from one highway to the crossing highway. The proposed staggered-diamond design requires only four, instead of eight, separate structures and hence greatly increases the feasibility of AHS infrastructure support. However, the reduced infrastructure complexity at such interchanges could still constrain considerably the design, operation and evolution of AHS. This is the focus of the second component. The staggered-diamond is also applicable to the design of eight additional highway-to-highway connector ramps directly connecting the manual HOV lanes on two crossing highways (assuming that the manual HOV lane is adjacent to the median). As in the case of AHS, the potential of (manual) HOV-lane concept can not be completely fulfilled without such direct highway-to-hjghway connector ramps. The provision of such HOV connector ramps could considerably speed up the manual HOV traffic and could be a significant additional incentive for ridesharing.
Jacob Tsao. "A Staggered-Diamond Design for Automated/Manual-HOV Highway-to-Highway Interchanges and Constraints on AHS Design for Accommodating Automated Highway Change" Intelligent Vehicle Highway Systems Journal (IVHS Journal) (1995): 281-292.