- Videos of the Institute
- Spectacular Examples of Hydraulic Drives and Actuators
- Videos of different pumps
Videos of the Institute
Hydraulic Buck Converter
The principle of the hydraulic buck converter (step down converter) corresponds largely with the electric buck converter (see the schematic of both devices). In the forward mode (to lift the load Flast) the pressure sided switching valve VP is operated in a pulse-width control mode. When the valve is on, the fluid in the inductance pipe (LH) is accelerated and when VP is off, the momentum of that fluid makes fluid from the tank line (pT) to be sucked into the system via the check valve VCHK,T. In this way much higher energetic efficiencies are achieved than with proportional valves, which just waste the surplus of pressure (pS-plast). This converter can recuperate energy when the load is lowered by a proper switching of the valve VT. Then it works as the hydraulic ram which is a step up converter.
This system requires quite high switching frequencies in the range beyond 50 Hz for a reasonable compactness.
Hydraulically Actuated Robotic Leg
The leg was developed by the Italian Institute of Technology. IMH tested the application of the hydraulic buck converter for a more efficient hydraulic actuation.
- Peng S., Kogler H., Guglielmino E., Scheidl R., Caldwell D.: The Use of a Hydraulic DC-DC Converter in the Actuation of a Robotic Leg, in: Proc. of the 2013 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2013), Tokyo, Japan, 2013.
- Guglielmino E., Semini C., Kogler H., Scheidl R., Caldwell D.: Power Hydraulics - Switched Mode Control of Hydraulic Actuation, in: Proc. 2010 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS 2010), October 18-22, 2010, Taipei, Taiwan, 2010.
- Kogler H., Scheidl R., Ehrentraut M., Guglielmino E., Semini C., Caldwell D.: A Compact Hydraulic Switching Converter for Robotic Applications, in: Proc. Bath/ ASME Symposium on Fluid Power and Motion Control - FPMC2010, September 15-17, 2010, Bath, UK, Page(s) 56-68, 2010.
- Guglielmino E., Semini C., Yang Y., Caldwell D., Scheidl R., Kogler H.: Energy Efficient Fluid Power in Autonomous Legged Robotics, in: Proc. 2009 ASME Dynamic Systems and Control Conference, Hollywood, California, 2009.