Hydraulic systems ensure there is the transmission of power by using the fluid pressure within a sealed system. Most of the brakes which are used in aircraft, cars among others apply the hydraulic principle (www.servi.no) . The reasons why hydraulic systems are more popular when compared to both the electrical and mechanical systems is because they offer a great number of advantages. Some of these advantages include generating more power within a small space. Fluid leakage from the system can cause a lot of problems and this can hinder the performance of the system and the system may stop working at all.
Working of the Hydraulics systems
When it comes to creating pressure hydraulic systems utilize liquids. Liquids are incompressible because they are made of too many particles which are close together (https://www.servi.no/service-og-vedlikehold/oljeanalyser/) . When the particles are in motion they tend to collide with each other. Since the pressure in liquids is equally distributed in every direction means if a force is applied at one point in a liquid is transferred to the other points on the liquid. Hydraulic systems working is based on the pascal principle where pressure is determined by the force applied divided by the cross-sectional area which should be in meters squared.
In hydraulic systems, when a small force is applied to a small cross-sectional area it transmits pressure and builds up a greater force over a large area (https://www.servi.no/var-produksjon/ventiler-og-ventilblokker/) . For instance, if you have two containers of different sizes and you connect them and on one cylinder you apply a force you will find out that the pressure generated is equal in both cylinders. Since one cylinder has a bigger volume it tends to produce a great force in spite of the pressure remaining constant in both cylinders.
The above is the working of the hydraulic system and some of the reasons its the most preferred choice for most manufacturers.