Hydraulics and pneumatics are both forms of fluid power, a common means of driving and controlling mechanical motions. It is one of the three kinds of power, with the other two being mechanical and electrical. Fluid power systems are widely used in most machinery, such as automobiles and construction equipment.
The National Fluid Power Association (1
) has an excellent introduction to the topic, which includes a general overview and descriptions of over 20 practical applications. It also looks at the current state of fluid power technology and how it has progressed in recent years. For a more detailed discussion of fluid power principles and how hydraulic and pneumatic devices operate, Integrated Publishing (2
) offers twelve chapters of material, complete with diagrams. Fluid Power Web (3
) is a comprehensive source of information about components, vendors, and software. Ideas and Applications is an especially interesting section, as it periodically gives a new article about clever, innovative ways of using fluid power systems. Every two months, the Fluid Power Society (4
) publishes a journal with a few articles about industry news and trends. Three specialized issues are offered each year, and there is an archive with issues that date back to 1998. A complete hydraulics system is broken down into its constituent parts and explained at this Web site (5
). The author uses many drawings and animations to illustrate the physical processes involved in hydraulics. The Institute of Hydraulics and Automation (6
), located at the University of Tampere in Finland, has a very active research program with many focus areas. Telerobotics, mobile hydraulics, cavitation, and virtual testing are all investigated at the institute, and project descriptions in each of these areas are given on the site. The Division of Fluid Power Technology (7
) at a Swedish university has developed a digital simulation tool for fluid power system design. Called HOPSAN, the software can be freely downloaded from the Web site to run on the Windows operating system (a Fortran compiler is required for Windows 95 and newer). Students at Purdue University (8
) have recently built "what is thought to be the first vehicle that uses water in all of its hydraulic systems." This article highlights the students' achievement and considers the rationale behind this original design.