Abstract: A novel force measuring device of simple design is provided with complementary stop surfaces protecting the device against over-loading. Alternatively, overloading is prevented by duplicating the force measuring device with two portions operating in opposite directions of force application. Such force measuring devices are advantageously incorporated in couplings between a motor driven vehicle and a further vehicle to be coupled thereto. Signals derived from these force measuring devices are used in a board computer for controlling the operation of the motor driven vehicle and the further vehicle coupled thereto.