in this paper the factor of safety (fs) and critical line-segments slip surface obtained by the alternating variable local gradient (avlg) optimization method was presented as a new topic in 2d. results revealed that the percentage of reduction in the fs obtained by switching from a circular shape to line segments was higher with the avlg method than other methods. the 2d-avlg optimization meth...

In this paper, a robust adaptive tracking control scheme is proposed for compensation of the stick-slip friction in a mechanical servo system. The control scheme has a sliding control input to compensate friction forces. The gain of the sliding control input is adjusted adaptively to estimate the linear bound of the stick-slip friction. By introducing the sliding control input, the global stabi...

Both active safety and fuel economy are important issues for vehicles. This paper focuses on a traction control strategy with an efficiency model in a distributed driving electric vehicle. In emergency situation, a sliding mode control algorithm was employed to achieve antislip control through keeping the wheels' slip ratios below 20%. For general longitudinal driving cases, an efficiency model...

This thesis treats different aspects of automotive control-systems and consists of four papers covering different areas in this large field. The first paper presents a 9-degrees-of-freedom dynamic model of a tractorsemitrailer vehicle, aimed at simulation and evaluation of active chassis-systems for stability enhancements. Special focus is put on inclusion of the dynamics of load transfer, whic...

In this paper, a robust wheel slip control system based on a sliding mode controller is proposed for improving traction-ability and reducing energy consumption during sudden acceleration for a personal electric vehicle. Sliding mode control techniques have been employed widely in the development of a robust wheel slip controller of conventional internal combustion engine vehicles due to their a...

Falls impose significant negative impacts to the US population and economy. A significant number of falls may be prevented via appropriate slip-responses since a strong relation exists between slips and falls. More importantly, as severe slips are more prone to result in a fall, identifying severe slippers along with the responsible factors for their adverse motor control and severe slipping sh...

In this work we present hardware and simulation results for control strategies towards series-elastic actuated (SEA) hopping systems. There is an abundance of work regarding the implementation of highly simplified hopper models, the prevalent example being the Spring Loaded Inverted Pendulum (SLIP) model, with the hopes of extracting fundamental control ideas for running and hopping robots. How...

One of the key topics in robotics is legged locomotion, taking inspiration from walking and bouncing gaits of bipeds and quadrupeds. A fundamental tool for analyzing running and hopping is the Spring Loaded Inverted Pendulum (SLIP), thanks to its simplicity but also effectiveness in modeling bouncing gaits. Being completely passive, the SLIP model does not have the ability to modify its net ene...