Abstract: A tractor unit (10) and a trailer unit (14) are connected by a connecting pin (33) on one unit (12, 14) which is in use received in an opening (21) in a connecting surface of the other unit, the connecting pin (33) including a sensor device (70) to sense loads imposed on the connecting pin (33) as the trailer unit (14) tends to decelerate or accelerate relative to the tractor unit (12), there being a control system, including a controller (65) which receives signals from the sensor device (70) representative of loads imposed on the connecting pin (33), and at least one electrical motive machine (50) is controlled, the machine (50) being capable of being electrically driven by power from an electrical storage device to provide drive to drive at least one ground engaging wheel (45a, 45b) and of generating electrical power for storage by an electrical storage device (58), such as to minimize the loads imposed on the connecting pin (33).

Abstract: A tractor unit (10) and a trailer unit (14) are connected by a connecting pin (33) on one unit (12, 14) which is in use received in an opening (21) in a connecting surface of the other unit, the connecting pin (33) including a sensor device (70) to sense loads imposed on the connecting pin (33) as the trailer unit (14) tends to decelerate or accelerate relative to the tractor unit (12), there being a control system, including a controller (65) which receives signals from the sensor device (70) representative of loads imposed on the connecting pin (33), and at least one electrical motive machine (50) is controlled, the machine (50) being capable of being electrically driven by power from an electrical storage device to provide drive to drive at least one ground engaging wheel (45a, 45b) and of generating electrical power for storage by an electrical storage device (58), such as to minimise the loads imposed on the connecting pin (33).

Abstract: A process of producing from an elongate tube a tubular structural component having a first longitudinal section integrally connected to a second longitudinal section, the second section being located at the end of the tube and being of a desired cross-sectional shape and size, the cross-sectional size of the second section being greater than that of the first section, the process including selecting a mandrel having a cross-sectional shape and size corresponding to the second section, relatively axially feeding said end of the tube over the mandrel in order to form said second section, the choice of the size of mandrel and the rate of feed and the axial pressure applied to said tube being controlled such that the wall thickness of the second section is on average at least 70 percent of the average wall thickness of the first wall section.