For Andrea's Research:
Monika's Research

Research Focus

Pump pressurization

Our research activities focus on two major areas - energy saving hydraulic drive systems and the development and optimization of pumps and motors. Current activities in the systems area include projects on new circuit solutions, appropriate mathematical modeling and simulation strategies, advanced actuator and drive line control concepts as well as methods for online prognostics and condition monitoring for agricultural and other mobile machines. The so-called "CASPAR" team focuses largely on improving unit efficiency and noise reduction in axial piston machines. In-house software such as CASPAR, AVAS and SUEZ are extensively used and continually developed to further increase our insight into the detailed inner workings of hydrostatic pumps and motors.

HIL test rig

Hydraulic Power Trains and Hybrid Systems

The focus is on new transmission concepts including advanced power train control strategies for off-road and on­road vehicles The goal of the research is to investigate ways to drastically reduce fuel consumption and emissions for different kind of vehicles. The research activities include:

  • Modeling and simulating of power trains using PSDD, an in­house MATLAB/Simulink Library
  • Performance prediction, including fuel consumption
  • New circuit solutions for continuously variable transmissions and hydraulic hybrids
  • Hardware-in-the-loop testing of power trains
  • Energy recovery concepts

Active Vibration Damping and Machine Diagnostics

Generic methods for online and on-board condition monitoring of hydraulic systems of off-road machinery are under development. The methods will indicate impending failures of complex hydraulic systems, even those that are properly maintined. The research also includes new concepts for active vibration control of off-road vehicles through the use of energy saving displacement controlled actuators, providing:

  • Improved ride comfort and additional fuel savings
  • Increased operator productivity and descreased fatigue
  • Flexible maintenance intervals due to online monitoring
  • Increased machine productivity and reliability, leading to more on-the-job hours
L15 Active Vib
Energy Saving Actuators

Energy Saving Actuators and Machine Power Management

Displacement controlled linear and rotary actuators are being proposed and invesitgated as possible solutions for substantial energy reductions in fluid power systems. The research focueses on new circuits, advanced control concepts, and power management strategies for multi-actuator, displacement controlled, systems. By replacing current resistance, or valve, controlled actuators, throttling losses can be nearly eliminated allowing for major fuel savings, while also allowing for the possibility of energy recovery during aiding loads. Feedback control, path coordination, and path optimization additionally increase machine productivity, effectively saving even more fuel to accomplish the same task. Details include:

  • Modeling of actuators and complex multi-domain, coupled, systems
  • Development of new controls and power management concepts
  • Experimental work using special actuator test rigs
  • Machine field testing

Multifunction Pump & Motor Test Rigs

The Maha Research Center has several special test rigs to support their research in the field of pump and motor development. This includes test rigs for:

  • Steady state measurements of pumps and motors
  • Low speed testing and startability measurement of motors
  • Dynamic performance of pumps and motors
  • Measurements of tribological systems, e.g., piston/cylinder interface and valve plate/cylinder block interface
  • Measurement of instantaneous cylinder pressure during real-time pump operation
  • Thermal measurement of valve plate/cylinder block interface
  • *NEW* Sound intensity measurement of pumps and motors
Special Test Rigs
CASPAR Micro Motion

Multi-Domain Modeling of Pumps and Motors

One of our primary research areas, the focus is on discovering the physical effects influencing energy dissipation in pumps and motors and to develop appropriate models describing these effects. Custom, in-house software tools are being extensively used and developed to predict the conditions and the load carrying ability of the flow through sealing and bearing gaps, considering non-isothermal gap flow, micro-motion of parts, and fluid-structure interaction. The ultimate goal is to predict energy dissipation and to find new methods for pump and motor design. The product of this research will allow:

  • Improved efficiency of pumps and motors
  • Increased power density
  • Descreased design time, with more accurate results

Noise Control and Acoustics

The goal for this area of research is to understand the sources of noise within hydraulic systems. The use of complex hydraulic systems has led to the demand for a more comprehensive understanding of audible noise. The utilization of axial-piston based hydraulic systems by numerous industries with a wide range of operating conditions has motivated our research to center on the design of a pump/motor or system. The Airborne Noise (ABN) emitted from the hydraulic system can be attributed to two main sources, namely, Fluid Borne Noise (FBN) and Structure Borne Noise (SBN). It is important that all projects consider both sources of noise.

CASPAR Pressure Field

Noise Reduction for Pumps, Motors, and Transmissions

Noise sources in pumps, motors, and the combination of the two in hydrostatic transmissions are being studied. The aim is to investigate the influence of pump and motor design on fluid-borne and structure-borne noise. Our custom software tools aid in reducing both of these primary noise sources. The full scope of research in this area includes:

  • Modeling of pump and motor noise sources
  • Transmission line modeling
  • Valve plate optimization
  • Measurement of airborne noise
CASPAR Pressure Field