Upper-body haptic system for snake robot teleoperation in pipelines

Snake robots have shown a great potential for operations in confined workplaces that are less accessible or dangerous to human workers, such as the in-pipe inspection. However, the snake robot teleoperation remains a nontrivial task due to the unique locomotion mechanism (e.g., helical motion) and the constraints of the workplaces including the low visibility and indistinguishable features. Most snake robot feedback systems are based on the live camera view only. It is hard for the human operator to develop a correct spatial understanding of the remote workplace, leading to problems such as disorientation and motion sickness in snake robot teleoperation. This study designs and evaluates an innovative haptic assistant system for snake robot teleoperation in the in-pipe inspection. An upper-body haptic suit with 40 vibrators on both the front and back sides of the human operator was developed to generate haptic feedback corresponding to the bottom and up sides of the snake robot, transferring the egocentric sensation of the snake robot to the human operator. A human-subject experiment (n = 31) was performed to evaluate the efficacy of the developed system. The results indicate that the proposed haptic assistant system outperformed other feedback systems in terms of both task performance and subjective workload and motion sickness evaluations. It inspires new control and feedback designs for the future snake robot in industrial operations.     

The development of an autonomous service robot. Implementation: “Lucas”—The library assistant robot

This paper describes an autonomous mobile device that was designed, developed and implemented as a library assistant robot. A complete autonomous system incorporating human–robot interaction has been developed and implemented within a real world environment. The robotic development is comprehensively described in terms of its localization systems, which incorporates simple image processing techniques fused with odometry and sonar data, which is validated through the use of an extended Kalman filter (EKF). The essential principles required for the development of a successful assistive robot are described and put into demonstration through a human–robot interaction application applied to the library assistant robot.     

A Human–Robot Cooperative Learning System for Easy Installation of Assistant Robots in New Working Environments

One of the applications of service robots with a greater social impact is the assistance to elderly or disabled people. In these applications, assistant robots must robustly navigate in structured indoor environments such as hospitals, nursing homes or houses, heading from room to room to carry out different nursing or service tasks. Among the main requirements of these robotic aids, one that will determine its future commercial feasibility, is the easy installation of the robot in new working domains without long, tedious or complex configuration steps. This paper describes the navigation system of the assistant robot called SIRA, developed in the Electronics Department of the University of Alcalá, focusing on the learning module, specially designed to make the installation of the robot easier and faster in new environments. To cope with robustness and reliability requirements, the navigation system uses probabilistic reasoning (POMDPs) to globally localize the robot and to direct its goal-oriented actions. The proposed learning module fast learns the Markov model of a new environment by means of an exploration stage that takes advantage of human–robot interfaces (basically speech) and user–robot cooperation to accelerate model acquisition. The proposed learning method, based on a modification of the EM algorithm, is able to robustly explore new environments with a low number of corridor traversals, as shown in some experiments carried out with SIRA.     

Robust Control Design of Wheeled Inverted Pendulum Assistant Robot

This paper examines the design concept and mobile control strategy of the human assistant robot I-PENTAR (inverted pendulum type assistant robot). The motion equation is derived considering the non-holonomic constraint of the twowheeled mobile robot. Different optimal control approaches are applied to a linearized model of I-PENTAR. These include linear quadratic regulator (LQR), linear quadratic Gaussian control (LQG), H₂ control and H_∞ control. Simulation is performed for all the approaches yielding good performance results.      

Optimization of layout and path planning of surgical robotic system

Positioning a surgical robot for optimal operation in a crowded operating room is a challenging task. In the robotic-assisted surgical procedures, the surgical robot’s end-effector must reach the patient’s anatomical targets because repositioning of the patient or surgical robot requires additional time and labor. This paper proposes an optimization algorithm to determine the best layout of the operating room, combined with kinematics criteria and optical constraints applied to the surgical assistant robot system. A new method is also developed for trajectory of robot’s end-effector for path planning of the robot motion. The average deviations obtained from repeatability tests for surgical robot’s layout optimization were 1.4 and 4.2 mm for x and y coordinates, respectively. The results of this study show that the proposed optimization method successfully solves the placement problem and path planning of surgical robotic system in operating room.

     

Walking intent detection algorithm for paraplegic patients using a robotic exoskeleton walking assistant with crutches

This paper deals with a walking intent detection algorithm for paraplegic patients using a robotic exoskeleton walking assistant with crutches. User intent detection is one of the most important factors for a robotic exoskeleton to recognize a user??s intent regarding robot operation and in order to conduct proper operation. For a robotic exoskeleton walking assistant, walking intent detection means that the robot recognizes the best time to start walking behaviors and which behavior should be executed from the user??s intent. To enable this detection, an algorithm derived from a finite Moore Automaton for Robot Behavior (MARB) has been developed. Also, a walking stability criterion model is presented for use in the proposed algorithm as a trigger signal for walking. The proposed algorithm and the walking stability criterion modeling were verified using the robotic exoskeleton walking assistant, ROBIN.     

Towards human motion capture from a camera mounted on a mobile robot

This article describes a multiple feature data fusion applied to a particle filter for marker-less human motion capture (HMC) by using a single camera devoted to an assistant mobile robot. Particle filters have proved to be well suited to this robotic context. Like numerous approaches, the principle relies on the projection of the model's silhouette of the tracked human limbs and appearance features located on the model surface, to validate the particles (associated configurations) which correspond to the best model-to-image fits. Our particle filter based HMC system is improved and extended in two ways. First, our estimation process is based on the so-called AUXILIARY scheme which has been surprisingly seldom exploited for tracking purpose. This scheme is shown to outperform conventional particle filters as it limits drastically the well-known burst in term of particles when considering high dimensional state-space. The second line of investigation concerns data fusion. Data fusion is considered both in the importance and measurement functions with some degree of adaptability depending on the current human posture and the environmental context encountered by the robot. Implementation and experiments on indoor sequences acquired by an assistant mobile robot highlight the relevance and versatility of our HMC system. Extensions are finally discussed.     

五指形仿人机械手的设计与实现及示教

设计和实现了一个具有五个手指和手掌的仿人机械手（以下简称仿人机械手）,并利用数据手套对其进行了示教,使其能有效地完成复杂的作业。首先,以现有的仿人机械手研究成果为基础,对仿人机械手进行了优化设计和实现;然后,以数据手套为示教源,对仿人机械手示教模型进行了研究,采用D-H变换矩阵建立了仿人机械手的逆向运动学,解决了示教运动映射问题。最后,利用仿人机械手进行了若干作业实验,实验结果证明了仿人机械手及其示教模型的正确性。     

Compact laparoscopic assistant robot using a bending mechanism

This paper presents the development of a compact laparoscopic assistant robot. The robot was designed to increase convenience and reduce possible interference with surgical staff by confining the majority of motions inside the abdomen. Its size was miniaturized as much as possible for convenient handling. A bending mechanism composed of several articulated joints was introduced to produce motions inside the abdomen. The proposed assistant robot can generate 3-DOF motion, including 2-DOF internal bending motion and 1-DOF external linear motion. Since the robot itself functions as a laparoscope, a small CCD camera module and a bundle of optical fibers were integrated as part of the system. For accurate control, mathematical modeling of the bending mechanism and a method of hysteresis compensation were introduced and implemented. For the control of the robot, a voice interface and a visual-servoing method were implemented. The performance of the developed system was tested through solo-surgery of in vivo porcine cholecystectomy. It was found that the views generated by the bending mechanism were sufficient throughout the surgery. Since the robot has functions comparable to the previously developed systems, while retaining its compactness, it is expected to be a useful device for human cholecystectomy.     

上肢康复训练机器人的研究进展及前景

利用机器人技术进行康复训练是康复治疗的重要手段之一。依据康复医疗训练机器人技术的发展意义及社会需求，结合该领域的研究背景、发展现状及趋势，回顾了国内外近些年来的研究进展和主要研究成果，分析了本地上肢康复训练机器人、基于网络的康复训练机器人和基于虚拟环境的康复医疗训练机器人的系统构造及其应用，着重介绍了一对多力觉辅助远程康复训练机器人系统的设计与特点，指出了待解决的问题，并分析了上肢康复医疗训练机器人在机械设计、控制器设计、力觉辅助、多路复用及评价策略等方面的发展趋势。     

Joint stiffness identification of six-revolute industrial serial robots

Although robots tend to be as competitive as CNC machines for some operations, they are not yet widely used for machining operations. This may be due to the lack of certain technical information that is required for satisfactory machining operation. For instance, it is very difficult to get information about the stiffness of industrial robots from robot manufacturers. As a consequence, this paper introduces a robust and fast procedure that can be used to identify the joint stiffness values of any six-revolute serial robot. This procedure aims to evaluate joint stiffness values considering both translational and rotational displacements of the robot end-effector for a given applied wrench (force and torque). In this paper, the links of the robot are assumed to be much stiffer than its actuated joints. The robustness of the identification method and the sensitivity of the results to measurement errors and the number of experimental tests are also analyzed. Finally, the actual Cartesian stiffness matrix of the robot is obtained from the joint stiffness values and can be used for motion planning and to optimize machining operations.     

Safety verification method for preventing friction blisters during utilization of physical assistant robots

This study is mainly concerned with the potential hazards of interactive friction force on a human–robot contact surface, which may result in various skin traumas, such as friction blisters. In this study, a novel safety verification method is developed for helping physical assistant robot users to avoid this hazardous condition. First, based on the microscopic structure of the epidermis–dermis layer and the characteristics of blisters on porcine skin, we prove that the porcine skin, instead of the human skin, is feasible as an innovative experimental material for generating friction blisters. Second, the conditions for generating blisters on porcine skin are confirmed using a series of adaptive time-gradient tests. Considering the properties of the censored results, we clarify an inherently safe region in the tangential traction–time relationship, which is based on a nonparametric estimation of the survival function on the subjects. After a condition-matching calculation, this region for the porcine skin is further verified to be consistent with that for the human skin. Third, the safety of the ‘stand-up and sit-down’ motion of a physical assistant robot user is successfully validated by applying this verification method, which finally proves its practical usability with regard to the possible physical stress hazard.     

Towards robotic assistants in nursing homes: Challenges and results

This paper describes a mobile robotic assistant, developed to assist elderly individuals with mild cognitive and physical impairments, as well as support nurses in their daily activities. We present three software modules relevant to ensure successful human–robot interaction: an automated reminder system; a people tracking and detection system; and finally a high-level robot controller that performs planning under uncertainty by incorporating knowledge from low-level modules, and selecting appropriate courses of actions. During the course of experiments conducted in an assisted living facility, the robot successfully demonstrated that it could autonomously provide reminders and guidance for elderly residents.     

Strongly Typed Term Representations in Coq

There are two approaches to formalizing the syntax of typed object languages in a proof assistant or programming language. The extrinsic approach is to first define a type that encodes untyped object expressions and then make a separate definition of typing judgements over the untyped terms. The intrinsic approach is to make a single definition that captures well-typed object expressions, so ill-typed expressions cannot even be expressed. Intrinsic encodings are attractive and naturally enforce the requirement that metalanguage operations on object expressions, such as substitution, respect object types. The price is that the metalanguage types of intrinsic encodings and operations involve non-trivial dependency, adding significant complexity. This paper describes intrinsic-style formalizations of both simply-typed and polymorphic languages, and basic syntactic operations thereon, in the Coq proof assistant. The Coq types encoding object-level variables (de Bruijn indices) and terms are indexed by both type and typing environment. One key construction is the boot-strapping of definitions and lemmas about the action of substitutions in terms of similar ones for a simpler notion of renamings. In the simply-typed case, this yields definitions that are free of any use of type equality coercions. In the polymorphic case, some substitution operations do still require type coercions, which we at least partially tame by uniform use of heterogeneous equality.     

Interpolation of orientation for precise path generation in industrial robots

Industrial robots are versatile mechanical systems that require accurate tracking of continuous end-effector trajectories. However, a variety of control problems are encountered due to the deviation between the desired and actual paths.In this study, a new continuous path planning method based on an interpolation of orientation scheme is applied for precise path generation in robot welding. This method guarantees minimum deviation of positioning and orientation errors. Also, a new trajectory error evaluation strategy is developed to describe the trajectory errors at the effect points, which are very important in some robot jobs such as arc-welding operations.The simulation study of circular motions in arc-welding operations shows the effectiveness of the proposed approach.     

Control Architecture for Human–Robot Integration: Application to a Robotic Wheelchair

Completely autonomous performance of a mobile robot within noncontrolled and dynamic environments is not possible yet due to different reasons including environment uncertainty, sensor/software robustness, limited robotic abilities, etc. But in assistant applications in which a human is always present, she/he can make up for the lack of robot autonomy by helping it when needed. In this paper, the authors propose human–robot integration as a mechanism to augment/improve the robot autonomy in daily scenarios. Through the human–robot-integration concept, the authors take a further step in the typical human–robot relation, since they consider her/him as a constituent part of the human–robot system, which takes full advantage of the sum of their abilities. In order to materialize this human integration into the system, they present a control architecture, called architecture for human–robot integration, which enables her/him from a high decisional level, i.e., deliberating a plan, to a physical low level, i.e., opening a door. The presented control architecture has been implemented to test the human–robot integration on a real robotic application. In particular, several real experiences have been conducted on a robotic wheelchair aimed to provide mobility to elderly people.     

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.     

Describing Upper-Body Motions Based on Labanotation for Learning-from-Observation Robots

We have been developing a paradigm that we call learning-from-observation for a robot to automatically acquire a robot program to conduct a series of operations, or for a robot to understand what to do, through observing humans performing the same operations. Since a simple mimicking method to repeat exact joint angles or exact end-effector trajectories does not work well because of the kinematic and dynamic differences between a human and a robot, the proposed method employs intermediate symbolic representations, tasks, for conceptually representing what-to-do through observation. These tasks are subsequently mapped to appropriate robot operations depending on the robot hardware. In the present work, task models for upper-body operations of humanoid robots are presented, which are designed on the basis of Labanotation. Given a series of human operations, we first analyze the upper-body motions and extract certain fixed poses from key frames. These key poses are translated into tasks represented by Labanotation symbols. Then, a robot performs the operations corresponding to those task models. Because tasks based on Labanotation are independent of robot hardware, different robots can share the same observation module, and only different task-mapping modules specific to robot hardware are required. The system was implemented and demonstrated that three different robots can automatically mimic human upper-body operations with a satisfactory level of resemblance.     

Automation of surface finishing processes

The development of robots capable of interacting dynamically with the environment has proven to be a difficult task. Since a majority of manufacturing tasks require interaction of robots with their environment, this has become an important focus for research in the industry. Solutions both to specific manufacturing operations and to the theoretical body of knowledge within the industry are extremely important. The interaction of the robot with its environment is investigated in this paper for the configuration of a quick actuator and sensor attached to the robot tool. This configuration has been tested in an industrial application for Steinway & Sons, the world renowned piano manufacturer, specifically for the automation of the labor-intensive rubbing and finishing operations. The robot architecture utilizes a combination of macro-micro manipulator to improve its response time. A quick actuator added to the end of the robot arm is the micromanipulator, and the robot arm is the macromanipulator. Force and impedance control laws are executed concurrently by two separate controllers to control the quick actuator and the robot arm respectively. The experimental system proves the ability of this configuration to follow the complex contour of a grand piano rim and to exert a given force while rubbing its surface.     

Three-dimensional model acquisition for medical robotics-assisted burn debridement system

This paper discusses the principles for the acquisition of a three-dimensional (3-D) computational model of the treatment area of a burn victim for a vision-servo-guided robot which ablates the victim's burned skin tissue by delivering a high-energy laser light to the burned tissue. The medical robotics assistant system consists of: a robot whose end effector is equipped with a laser head, whence the laser beam emanates, and a vision system which is used to acquire the 3-D coordinates of some points on the body surface; 3-D surface modeling routines for generating the surface model of the treatment area; and control and interface hardware and software for control and integration of all the system components. Discussion of the vision and surface modeling component of the medical robotics assistant system is the focus of this paper. The robot-assisted treatment process has two phases: an initial survey phase during which a model of the treatment area on the skin is built and used to plan an appropriate trajectory for the robot in the subsequent phase—the treatment phase, during which the laser surgery is performed. During the survey phase, the vision system employs a camera to acquire points on the surface of the patient's body by using the camera to capture the contour traced by a plane of light generated by a low power laser, distinct from the treatment laser. The camera's image is then processed. Selected points on the camera's two-dimensional image frame are used as input to a process that generates 3-D body surface points as the intersection point of the plane of light and the line of sight between the camera's image point and the body surface point. The acquired body surface points are then used to generate a computational model of the treatment area using the non-uniform rational B-splines (NURBS) surface modeling technique. The constructed NURBS surface model is used to generate a treatment plan for the execution of the treatment phase. The robot plan for treatment is discussed in another paper. The prototype of the entire burn treatment system is at an advanced stage of development and tests of the engineering principles on inanimate objects, discussed herein, are being conducted.