All the fun of the fair This article takes a look at how widely are sensors used at fair grounds and how they time and position each ride, to a split second and keep us and the rides safe. Not all the applications of non-contact sensor uses are serious and technical, probably the last place you would think of finding sensors is one place dedicated to fun and enjoyment the fun fair! The popular traditional fun fair carousel is one such attraction that makes use of non-contact position sensors to keep the horses or other models rising and falling to the right heights. They move up and down on hydraulic cylinders that are controlled by the feedback gained from the sensors detecting the position of the model at any given point. This level of control over each individual model makes the ride run smoothly, with each model following the gentle up and down motion as the carousel turns. The sensors also come into play when the ride ends, as each model needs to return to the base position so the passengers can disembark.Rotary non-contact sensors can be used on rides like the magic teacups, to ensure that the cars stop with the openings in the right position for the customers to get in and out. These same rotary sensors can also be used to measure and control the speed at which the cups spin; some variations of the magic teacups can be operated at a low speed only for small children, and then sped up for groups of older people. The ability to measure the spin speed also means that if one of the cups is faulty and is going too fast, or in an unusual pattern it can be detected and repaired.On more thrilling rides, such as rollercoasters, non-contact sensors play a very important role in several areas. Often the larger rides with a long track, will have more than one car going round at any one time, in order to get more people on the ride over the course of the day (just imagine how much longer the queue would be if there were only one car compared to two or three), but there is a safety concern over the failure of one of these cars to complete a section and the ensuing crash between the stopped car and the one behind it. Sensors are placed at various points on the track to record each car passing at the right time. If a sensor fails to detect the car passing, the entire ride will shut down instantly until the stopped car has been recovered.Sensors that detect whether the shoulder or lap bars are properly locked also have the ability to stop the ride, to ensure that the car does not leave unless every passenger is locked in safely. This is why ride attendants will close every safety bar, even in empty seats before the ride leaves, as it cannot go without every safety belt being detected as closed. When the ride finishes the car always stops in the same place, allowing passengers off one side and on the other. Again, it is a sensor that detects the car entering the last phase of the ride and starts to slow the car down, applying the brakes fully at the point where the ride needs to stop. Sensors are also used to set off the camera to take unflattering pictures of people screaming on the ride.It is very important that non-contact sensors are used in theme parks and funfairs, as contact switches will wear out very quickly due to the repeated motion and contact between the two parts. Non-contact sensors do not suffer the same wear and tear and only need to be replaced as part of routine maintenance or when they are broken for other reasons. Article published on: 30/12/2016 Article last updated on: 30/12/2016