Position sensors on actuators

We look at the important role that position sensors play when fitted to actuators in ensuring precision is always met together with the data they generate.

Actuators are used in nearly every moving piece of equipment, from automatic doors to oil refinery equipment, from cars to luxury yachts. Traditionally they use hydraulic technology to effect the linear movement, as a small initial force can be easily translated into a larger output force and they are reliable, able to cope with heavy loads and challenging environments. Electric actuators are becoming more popular, but as they are relatively new there are limitations on what they are capable of moving, so product designers often stick with hydraulic actuators for their reliability and capability.

Position sensors fitted to actuators, whether hydraulic or electrical, measure the distance of travel and play a very important role in the accurate operation of these actuators, ensuring that they stop at a pre-defined place and only move as far as they are supposed to. In processing industries especially, the accuracy and reliable operation of actuators is imperative for monitoring the operation of the machinery and identifying quickly when things are not working as they should, thereby reducing downtime and wastage.

The data generated by linear position sensors fitted to actuators can be used to ensure the safe and reliable operation of the equipment it is fitted to, with real-time monitoring possible for many applications where consistency is vital. This data can also be analysed to inform decisions about maintenance schedules, as differences in the measurements gathered by the linear position sensors can identify the point at which a piece of machinery starts to operate differently, suggesting a need for maintenance. Parts that need frequent replacement due to wear and tear and those that need regular lubrication are good candidates for being fitted with position sensors that can detect those small changes in operation that mean some intervention is needed.

The data gathered from sensors on actuators in machinery can be used not only to inform a maintenance schedule that leads to increased productivity, but also to inform the design of the next generation of any type of machinery that uses actuators, or in fact any moving parts in equipment. By combining the information about the changes in preventative maintenance schedules that are driven by data feedback with the design process of a new version, it is possible to engineer a solution to frequent maintenance by designing out the causes of wear and tear in the first place, or by designing in a lubrication system for example. It is also possible to design a piece of equipment that is built with linear position sensors to begin with, rather than these being fitted retroactively. The ongoing use of sensors and the data they generate means that the process of intelligent design and reducing maintenance downtime can continue even with the new equipment.

In the case of linear position sensors being fitted to the suspension in the Formula Student Spain race team, that Positek sponsors, this data is used to inform the design of better suspension systems and new types, and although there are no actuators used in the suspension system, it is a good example of how the data gathered by linear position sensors can be used in the design process of the next stage of developments. Not only can changes be made to the suspension set up during testing, but the same data can be used in the design and specification of their new style of suspension. We will be bringing you an update soon on how the race team is getting on and how our sensors are helping them to improve their car design.