Having a family with a predisposition towards travel sickness is often a problem. I’d like a journey planner which could not only find me the shortest path between A and B, or avoid toll roads, but could also indicate the route which was least likely to require me to hose out the car later.

Today’s invention is a simple algorithm which can be used to calculate a value for the nausea potential of any road journey. Conventional online road planners already assign a value for sensible speed to any point on a journey. Using this value of local speed, it’s easy to calculate the accelerative forces (‘g’) on passengers, which I believe are what cause the illness.

I assume that experiencing a high ‘g’ force for a longer time causes a proportional increase in sickness. At any point on the road for which the speed v is known, the instantaneous queasiness index q is given by v/r (where r is the radius of curvature of the road at any point). Totalling this along the length of a number of candidate routes would allow the least unpleasant travel experience to be selected (the one with smallest total q).

This approach might be easily be extended to include g forces associated with driving up and down hills.