Development of Compact Automated Benchtop Pressure Generator Platform Capable of Dynamic Pressure Control up to 7 kilobar
Hydrostatic pressure in the range up to several thousand bars is now recognized to have fundamental effects on the structure and function of biological systems ranging from proteins, cell, to whole organisms. Much of the high pressure equipment in use for biological applications, however, continues to be a domain for do-it-yourself enthusiasts and is not, therefore, well suited for adoption by vast majority of life science laboratories. The HUB series of pressure generators was conceived to offer life scientists a highly flexible, compact, yet simple to use source of high pressure. While high pressure research will always require some equipment customization, the availability of “plug-and-play” pressure generators will greatly simplify the required effort. Computer-based data acquisition and control allows easier integration of the pressure generator into an experimenter’s custom setup. The individual instruments of the HUB series contain compressed airdriven intensifiers with piston cross-section area ratios of 1:160; 1:440 and 1:880, respectively, resulting in generation of the hydrostatic pressure up to 7,000 bar, depending on the model. This presentation highlights two advanced software control features of the HUB pressure generators. One uses proportional–integral–derivative (PID) algorithms to maintain precise (±0.01%) static pressure despite the effects of temperature fluctuation (and associated thermal expansion), and non-zero seal friction. The second illustrates the use of an active control algorithm to enable a constant pressure intensifier to emulate a constant displacement (flow rate) pump, within a defined band of operation.