  The problem of maximizing the probability of two trucks being coordinated to
merge into a platoon on a highway is considered. Truck platooning is a
promising technology that allows heavy vehicles to save fuel by driving with
small automatically controlled inter-vehicle distances. In order to leverage
the full potential of platooning, platoons can be formed dynamically en route
by small adjustments to their speeds. However, in heavily used parts of the
road network, travel times are subject to random disturbances originating from
traffic, weather and other sources. We formulate this problem as a stochastic
dynamic programming problem over a finite horizon, for which solutions can be
computed using a backwards recursion. By exploiting the characteristics of the
problem, we derive bounds on the set of states that have to be explored at
every stage, which in turn reduces the complexity of computing the solution.
Simulations suggest that the approach is applicable to realistic problem
instances.
