Brake by wire control with pedal feedback and brake boost

"By wire" technology merged into multiple vehicular subsystems, including gear changing, drive, and braking systems. The brake by wire system is developed to overcome the problems associated with the integration of mechanical and hydraulic systems in novel vehicular systems. Even though brake by wire systems has potential advantages, the conventional brake systems' tactile sensation will be removed if migrated to the electrical by wire control scheme. This paper proposes a novel control mechanism that provides amplification of force, scaling of position replication, and a virtual spring-damper based pedal retraction which provides bilateral brake force feedback to the driver's pedal similar to the hydraulic brake system. The proposed system performance was simulated and tested using a bilateral teleoperation system with disturbance observers (DOB) and reaction force observers (RFOB). The proposed system provides pedal force amplification and brake force feedback to the driver's pedal using RFOBs. The virtual spring retracts the brake pedal, similar to a mechanical pedal retraction system. The system simulation and experimental results provide evidence of the proposed system's force amplification, position scaling, and pedal reaction capabilities.

Robust H∞ control of an uncertain bilateral teleoperation system using dilated LMIs

A robust state-feedback [Formula: see text] controller is proposed for an uncertain bilateral teleoperation system having norm-bounded parametric uncertainties on mass and damping coefficients of the considered master/slave system. The proposed method ensures robust stability and successful reference tracking and force reflection performance. While Lyapunov stability is used to ensures asymptotic stability, the [Formula: see text] norm from exogenous input to the controlled output is utilized in satisfying the reference tracking and force reflection. As two performance objectives and robust stability requirement are conflicting with each other, the proposed controller reduces the associated conservatism with dilated linear matrix inequalities. Standard and dilated linear matrix inequality-based robust [Formula: see text] state-feedback controllers are performed with a one degree of freedom uncertain master/slave system under reference signal and environmental-induced exogenous force. Numerical simulation results show that the dilated linear matrix inequality-based [Formula: see text] control satisfies lower [Formula: see text] norm than a standard [Formula: see text] control. Moreover, the proposed controller demonstrates a very successful performance in achieving performance objectives despite the stringent norm-bounded parameter uncertainties.

Bilateral teleoperation with object-adaptive mapping

Task space mapping approaches for bilateral teleoperation, namely object-centered ones, have yielded the most promising results. In this paper, we propose an invertible mapping approach to realize teleoperation through online motion mapping by taking into account the locations of objects or tools in manipulation skills. It is applied to bilateral teleoperation, with the goal of handling different object/tool/landmark locations in the user and robot workspaces while the remote objects are moving online. The proposed approach can generate trajectories in an online manner to adapt to moving objects, where impedance controllers allow the user to exploit the haptic feedback to teleoperate the robot. Teleoperation experiments of pick-and-place tasks and valve turning tasks are carried out with two 7-axis torque-controlled Panda robots. Our approach shows higher efficiency and adaptability compared with traditional mappings.

Aerial Tele-Manipulation with Passive Tool via Parallel Position/Force Control

This paper addresses the problem of unilateral contact interaction by an under-actuated quadrotor UAV equipped with a passive tool in a bilateral teleoperation scheme. To solve the challenging control problem of force regulation in contact interaction while maintaining flight stability and keeping the contact, we use a parallel position/force control method, commensurate to the system dynamics and constraints in which using the compliant structure of the end-effector the rotational degrees of freedom are also utilized to attain a broader range of feasible forces. In a bilateral teleoperation framework, the proposed control method regulates the aerial manipulator position in free flight and the applied force in contact interaction. On the master side, the human operator is provided with force haptic feedback to enhance his/her situational awareness. The validity of the theory and efficacy of the solution are shown by experimental results. This control architecture, integrated with a suitable perception/localization pipeline, could be used to perform outdoor aerial teleoperation tasks in hazardous and/or remote sites of interest.