The Fluid Power and Mechatronic Section carries out research within the areas of control, energy usage and systems optimisation of fluid power mechatronic systems. Research activities include the following main areas:
- Control of Fluid Power Motion Control Systems
- Automated Design Procedures
- Energy Usage in Mobile Hydraulic Applications
- Hydraulic Control Valves
- Autonomous Vehicles for the Agricultural Sector
- Fault-tolerant Electro-hydraulic Steering of Industrial Vehicles.
Control of Fluid Power Motion Control Systems
General research is done in the area of motion control of hydraulic machinery. Of selected areas may be mentioned active damping of oscillations in hydraulic vehicles and tool centre control of hydraulic robot manipulators, mobile hydraulic cranes and excavators.
The activities include sophisticated modelling, analysis, simulation and experimental verification of components, subsystems and systems to be controlled. Applied control deals with both linear and non-linear control theory, and includes among others adaptive controllers, active damping approaches and inverse modelling techniques combined with optimisation theory for determining optimal controller settings and avoiding instability as often encountered in hydraulic systems.
Automated Design Procedures
The design process of fluid power mechatronic systems is a complicated task, requiring substantial expert knowledge to obtain satisfactory performance. Research is carried out to develop systematic methods for the design, component sizing and controller development for such systems, using optimisation techniques for topological and dimensional synthesis, as well as controller parameter adjustment.
The research deals with both serial and concurrent synthesis procedures and is based on Predictable Desing Performance. Part of the research will be a deal of the PhD project Electric Load Sensing and Power Management in Mobile Hydralic Applications.
Energy Usage in Mobile Hydraulic Applications
Energy Usage in hydraulic systems is one of the prime factors of concern today in developing new systems, as generally systems efficiency of hydraulic systems are low. Research is carried out on a number of applications to determine the energy usage and distribution in these, in order to be able to better utilise the energy, through redesigned and improved control of the systems.
As the energy effiency is highly related to the hydraulic system layout, part of the research is done in connection with the above mentioned research in Automated Design Procedures for developing methodologies for system design, in which system efficiency is one of the prime objectives. The research goal is to develop hydraulic systems with better system efficiency and performance to meet future demands.
Hydraulic Control Valves
Increasing demands for the performance of hydraulic systems has set new demands for hydraulic valves, and research is carried out to determine requirements for future valves and how these should be designed. Current research is on developing a new proportional control valve for use in mobile hydraulics which is capable of gulfilling the dynamic, efficiency and controllability requirements of future hydraulic systems. The project is carried through as a industrial PhD project in collaboration with Sauer-Danfoss. Research as well covers new and/or improved techniques for actuation of the spools.
Autonomous Vehicles for the Agricultural Sector
At present an autonomous vehicle platform with independent steering, traction and height adjustment on all four wheels is being developed at the department and the first control stategies for controlling the height adjustments and active suspension are being tested. Future research will ge towards energy efficiency control of the diesel engine and pump to just meet the power requirements in the system, besides developing control strategies for traction control, steering and coordination of all these functions under driving.
Fault-tolerant Electro-hydraulic Steering of Industrial Vehicles
A new concept for steering equipment known as steer-by-wire (SbW) is increasingly revieving focus in the industrial/agricultural vehicle sector. The SbW concept is characterized by the replacement of the steering column by a digital commucation wire. While this concept introduces advantages such as more freedom for cabin design, simplified assembly procedures and increased driver comfort it also introduces a safety issue not present in conventional manual and servo-assisted steering equipment. The vehicle operator is unable to manually turn the steering wheels by muscular means in case of a malfunction in the SbW steering equipment. As a consequence SbW steering equipment must be designed in a way to tolerate any single potential dangerous failure. This research project focuses on developing such fault-tolerant electro-hydraulic steering architectures.