linear state bisection is introduced as a new method to find time-invariant state feedback control laws for a special form of underactuated nonlinear systems. the specialty of the systems considered is that every unactuated state should be coupled with at least two directly actuated states. the basic idea is based on bisecting actuated states and using linear combinations with adjustable parame...

In this paper, a complete solution on the suboptimal feedback control law synthesis for underactuated systems, based on the general optimization framework of the Dynamic Programming Theory is introduced. Control method proposed keeps the general structure of a suboptimal control approach, while the functional defining performance index is based on the underactuated system energy. Some numerical...

In this paper, we present a control algorithm to control underactuated mechanical systems that evolve in the configuration space with the fiber bundle structure. We show that by using the geometric tools such as symmetric product, and small amplitude periodic forcing, we can develop unique techniques to control the underactuated dynamic system, such as an unmanned blimp.

The authors consider the control of an underactuated mechanical system: Pendubot, which has four separated equilibrium points. A unified controller is proposed to stabilise the system at the four equilibrium points. Moreover, the proposed unified control can bring the underactuated link to ideal homoclinic orbits, which cannot be achieved by existing approaches. Simulation results verify the ef...

A manoeuvring model and a design technique for path following applications of underactuated underwater vehicles are summarized. The model applies to slender body autonomous underwater vehicles (AUV) of cylindrical shape employing similar types of steering and diving control surfaces, and is meant for low speed manoeuvring applications. The underactuated design procedure used to successfully sol...

In this paper, we introduce cascade normal forms for underactuated mechanical systems that are convenient for control design. These normal forms include three classes of cascade systems, namely, nonlinear systems in strict feedback form, feedforward form, and nontriangular quadratic form (to be defined). In each case, the transformation to cascade systems is provided in closed-form. We apply ou...

In this paper, we introduce cascade normal forms for underactuated mechanical systems that are convenient for control design. These normal forms are partially linear which results from a well-known fact that un-deractuated systems can be partially linearized using a change of control 12]. The diiculty arises when the new control appears both in the linear and nonlin-ear subsystems. We introduce...

In recent years, researchers have been dedicated to the study of underactuated manipulators which have more joints than control actuators. In previous works, one always assumes that there is enough dynamic coupling between the active and the passive joints of the manipulator, for it to be possible to control the position of the passive joints via the dynamic coupling. In this work, the authors ...

The development of universal grippers able to pick up unfamiliar objects of widely varying shapes and surfaces is a very challenging task. Passively compliant underactuated mechanisms are one way to obtain the gripper which could accommodate any irregular and sensitive grasping object. The purpose of the underactuation is to use the power of one actuator to drive the opening and closing motion ...