Abstract: The system comprises a spring between the vehicle body and each wheel, a shock absorber associated with each spring and which is switchable electromagnetically between soft and hard settings, one or more accelerometers measuring vertical acceleration of the vehicle body, an electronic filter for filtering the signals from the accelerometer to select a band width of frequencies, either side of the primary ride frequency of the vehicle, and control means for switching the shock absorbers between the soft and hard settings whenever a pre-determined level of vertical motion within this band width is exceeded either in the bump or rebound directions.

Abstract: A method of, and system for, spraying is provided in which voltages generated by the passage of pressurized medium through a spray nozzle is monitored. The generated voltage has characteristic patterns. Monitoring the variations in these patterns or the exceeding of predetermined voltage limits enable close control to be monitored over the spraying operation and for remedial action to be taken in due time.