V.F. Muñoz

The autonomous mobile robot AURORA for greenhouse operation

AURORA has been conceived in order to substitute hard and unhealthy human work inside greenhouses by means of an autonomous mobile robot outfitted with appropriate sensors and operation devices. Emphasis has been put in the development of a new robotic platform specifically designed for greenhouse tasks, governed by a control architecture that supports both autonomous navigation and shared human control.

Mobile robot trajectory planning with dynamic and kinematic constraints

This paper presents methods for planning mobile robot trajectories by considering the kinematic and dynamic constraints on the vehicle motion. The resulting path is smooth and quasilinear in curvature variations. The maximum value of the curvature can be assured to be smaller than the value given by the constraints. Furthermore, speeds along the path are planned subject to the kinematic and dynamic constraints. The resulting trajectories provide ideal conditions for high precision path tracking and positioning. In the paper we present the application of the proposed methods to RAM-1, a new mobile robot designed and built for indoor and outdoor industrial environment.<<ETX>>

A new robotic endoscope manipulator. A preliminary trial to evaluate the performance of a voice-operated industrial robot and a human assistant in several simulated and real endoscopic operations.

We report our learning experience in simulated and real surgical tasks with a new voice-controlled robotic endoscope manipulator: an industrial robot with the tool-holder arm modified to support the optic and camera. The manipulator control-card programs have been rewritten to meet the needs of endoscopic surgeons. For this preliminary work, systems engineers with an additional monitor monitored, recorded, and compared the percentage effectiveness and precision of the responses of the robotic and human assistant to successive oral commands during the several different experimental surgical tasks. Simultaneously, to help develop this voice-commanded system for future, more precise robotic manipulation of surgical instruments, they measured the cartesian and spherical coordinates of successive positions of the optic. In unexpectedly difficult experimental conditions, the tireless robot proved more precise and effective than the demonstrably fatigable human: the steadier screen images of the robotic manipulations helped the surgeon tie knots in 7–0 sutures.

Human-machine interface evaluation in a computer assisted surgical system

This work presents an approach to the evaluation of two interfaces for the control of a robotic surgical assistant. Each interface is associated to a different mode of controlling the system: by the surgeon (voice commands) or by the assistant (tactile interface). This two modes are allowed by the design of the manipulator, developed to occupy a small volume in the operating room. To evaluate the interfaces, a rating scale for teleoperated systems is proposed.

Adaptive cartesian motion control approach for a surgical robotic cameraman

This paper presents an adaptive trajectory planning method concerning to the robotic assistant ERM (endoscopic robotic manipulator), designed and developed by the authors for handling the camera in laparoscopic surgery. In order to emulate the human assistant, camera movements must be defined relative to the fulcrum point, where the optic passes through the patient skin and enters inside the abdominal cavity. Since the robot has a passive wrist, and it is not fixed to the operating table, the relative position between the robot camera holder and the insertion point is unknown. In this way, the proposed approach keeps the camera orientation according to the motion references in spite of this uncertainty, and compensates other unexpected disturbances about the relative robot-patient position. This motion planner is based on a schema of a cartesian motion controller with inner joint position-velocity loop, and has been tested by means of experimentation with alive animals.

Control architecture for mobile robot operation and navigation

Abstract This paper presents the navigation and operation system (NOS) for a multipurpose industrial autonomous mobile robot for both indoor and outdoor environments. This architecture supports task specification in terms of an event-driven state-based machine that provides high quality mission performance in uncertain environments. All processes in the NOS have been integrated in a distributed architecture designed to consider the real-time constraints of each control level of the system. Particular task models obtained from the system requirements specifications are integrated at the highest level of the architecture so that the rest of the levels remain unchanged for a wide range of industrial applications, such as transportation and operation with onboard devices.

Using human state aware robots to enhance physical human-robot interaction in a cooperative scenario

Human motor performance, speed and variability are highly susceptible to emotional states. This paper reviews the impact of the emotions on the motor control performance, and studies the possibility of improving the perceived skill/challenge relation on a multimodal neural rehabilitation scenario, by means of a biocybernetic controller that modulates the assistance provided by a haptic controlled robot in reaction to undesirable physical and mental states. Results from psychophysiological, performance and self assessment data for closed loop experiments in contrast with their open loop counterparts, suggest that the proposed method had a positive impact on the overall challenge/skill relation leading to an enhanced physical human-robot interaction experience.

Dynamic speed planning for safe navigation

The paper deals with speed control for autonomous mobile robots. First a trajectory planner attaches a speed component to the postures of a path by considering speed limitations introduced by the vehicle and by task specifications. In order to provide robustness during task execution in the real world, environment feedback is used to dynamically adjust the speed of the vehicle to the presence of unexpected obstacles, both static and mobile. This is accomplished by combining the planned speed profile with the outputs of two reactive controllers. The system has been successfully implemented within the control architecture of the RAM-2 mobile robot.

Pivoting motion control for a laparoscopic assistant robot and human clinical trials

This paper presents a compliant motion control method for the robotic assistant ERM (Endoscopic Robotic Manipulator), designed and developed by the authors for handling the camera in laparoscopic surgery. Since the robot has a passive wrist and it is not fixed to the operating table, the relative position between the robot camera holder and the insertion point is unknown. In this way, the proposed approach keeps the camera orientation according to the motion references in spite of this uncertainty and compensates for other unexpected disturbances about the relative robot–patient position. This system has been tested with live animals as well as in clinical trials on humans.

Parallel force-position control scheme with fuzzy gain tuning for single port laparoscopic surgery

This paper proposes a navigation method for manipulators which handle a surgical instrument or robotic platform introduced through a SILS multiport trocar. This method is based on a parallel position and force control which allow to the manipulator makes movements around the fulcrum point making the minimum force in the patients abdomen. In order to avoid the hysteresis effect due to the space between the instrument and the trocar when the instrument is inserted, a fuzzy gain scheduler has been designed. These algorithms have been implemented in a six degrees of freedom manipulator with a force sensor in the end effector. Finally, the experimental results are shown in order to demonstrate how it works in a real environment.