Robot Control Modes Research Articles

Model-based hardware in the loop control of collaborative robots

Simulation and model-based design software packages are widely used in many engineering disciplines. When it comes to robotics those tools are very important for robot design, simulation and the development of control algorithms before the implementation on the real robot. Simulink by MathWorks® is an advanced model-based design tool. It is popular in education, industry and research. In addition, Simulink supports several hardware components, facilitating a rapid deployment of the developed programs on the target hardware. In this study, the SimulinkIIWA interface for controlling KUKA iiwa robots from Simulink is presented and compared to the KUKA Sunrise Toolbox (KST). This interface is based on the User Datagram Protocol (UDP) and allows graphical real-time control of iiwa robots from Simulink without a need for writing any code. The interface supports different robot control modes, at the joints level and at the end-effector (EEF) level. Example applications are also provided showing the flexibility and the ease of use of the proposed interface.

A Robotic Platform for 3D Forelimb Rehabilitation with Rats.

In an attempt to promote greater functional recovery after spinal cord injury, researchers have begun exploring combinatorial treatments, such as robotic rehabilitation combined with stem cell transplantation. Since these treatment methods are in their nascent stages, rodent models have been proposed for initial investigations. Robots have been built for locomotion rehabilitation and planar forelimb reach and grasp assessment with rodents; however, a robotic platform suitable for three-dimensional movement rehabilitation of the rodent forelimb has not yet been developed. In this paper, a novel three degree of freedom robotic manipulator for automated forelimb rehabilitation combined with stem cell transplantation after cervical spinal cord injury with rats is proposed. The robot interfaces with a rat in an end-effector manner, measuring and interacting with the forelimb in the 3D Cartesian space. In this work, we trained two rats through behavioral shaping to actively interact with the device during two robot control modes. This work provides preliminary investigations into the feasibility of 3D forelimb rehabilitation with rats, which could be translated as a paradigm for combinatorial treatments after spinal cord injury in a controlled manner.

Safety Control Method of Robot-Assisted Cataract Surgery with Virtual Fixture and Virtual Force Feedback

Surgery is an effective means of treating cataracts and restoring vision. However, cataract surgery rate (CSR) in developing countries and regions is relatively low due to the lack of experienced high-level surgeons. In this paper, to reduce the reliance of surgery on physician experience and thereby increase CSR, a master-slave robotic system and safety control strategies with a virtual fixture and virtual force feedback are proposed to assist cataract surgery. First, the surgery is divided into four different stages with different robot control modes. Secondly, the virtual constraint area with virtual spring model in the operating stage is established, so that the doctor can distinguish the operation area where the end of the surgical instrument is located by feedback force. Thirdly, safety control algorithm guarantees that the surgical instrument strictly moves around the surgical incision point, which is regarded as a remote centre of motion, so that the cornea outside the incision point is not injured. Finally, the experimental results show that the proposed safety control strategy allows the robotic system to perform the procedure safely.

An assigned responsibility system for robotic teleoperation control

This paper proposes an architecture that explores a gap in the spectrum of existing strategies for robot control mode switching in adjustable autonomy. In situations where the environment is reasonably known and/or predictable, pre-planning these control changes could relieve robot operators of the additional task of deciding when and how to switch. Such a strategy provides a clear division of labour between the automation and the human operator(s) before the job even begins, allowing for individual responsibilities to be known ahead of time, limiting confusion and allowing rest breaks to be planned. Assigned Responsibility is a new form of adjustable autonomy-based teleoperation that allows the selective inclusion of automated control elements at key stages of a robot operation plan’s execution. Progression through these stages is controlled by automatic goal accomplishment tracking. An implementation is evaluated through engineering tests and a usability study, demonstrating the viability of this approach and offering insight into its potential applications.

Study relevance of an assistance robot for the elderly in institution

Study relevance a priori of a mobile service robot dedicated to seniors living in institution. The robot have three functionality: moving support for the fragile person, orientation help of the cognitively vulnerable person and assistance to carry the personal objects. Beforehand, a slide show was presented suggesting the potential functionality of the robot. Then residents answered semi-structured interview and questionnaire about issues related to five areas: safety, operability, functionality, and mutual support, design. Sixty-two residents were interviewed. 82,3% of residents think that robot acts as an ordinary tele-alarm. The favourite robot's control mode was the voice (82.6%). The robot was rarely viewed as a companion, but it offered for anyone the image of a servant device to support the resident when moving, guidance as well as carrying objects. Fifty percent of the residents appreciated the three robot's functions especially in case of loss of autonomy. Residents preferred basin height for the robot, while standing. Whatever, the robot presented through a simulation was still subject of surprise and interrogation for 42% of the residents. Finally, the residents attached more importance to the functionalities compared to the design. This study shows that the accession of the elderly to the robot in an institution is very nuanced. The assessment is potentially biased by the difficulty of the very old person to project into the possible use of such a device. The function of security or reinsurance dominates the expectations to compensate for the delay of intervention of caregivers particularly at night and/or the discomfort to produce the call. However, this type of investigation can offer designers all the negative and/or positive representations aroused by such a device and warns about the need to offer immediately a simple but very functional prototype to convince users and financers.

Some interactive control modes for planar cable-driven robots

This paper presents the design and the implementation of a multimodal operator interface dedicated for planar cable-based robots. Three interactive robot control modes which have been implemented are namely point and click based control, gesture-based control and voice based control. Point and click based control enables robot control by simply clicking on features appearing on images of the robot workspace. Gestural-based control enables robot control by means of human operator gestures. Voice based control enables robot control by means of natural speech. Successful experiments have been tested on a homemade planar cable-driven robot. The availability and the combination of these three modes improve greatly the capability of the global system.

Human Performance with Vocal Cueing of Automation State Changes in an Adaptive System

Previous research on cueing of control mode changes in adaptive systems has focused on the use of visual cues with some work on complex auditory cues. Research has not explored the use of vocal cues for automation state changes and human performance implications. This study investigated vocal cues as feedback on adaptive robotic system states for supporting operator performance when responding to control mode transitions compared with visual (icons) and auditory (earcons) feedback. Thirty-two participants performed a virtual reality simulation of a telerobot-assisted underwater mine disposal task. Modal cues were presented with task phase changes and robot control mode changes. Cue type and complexity (length of messages) were varied between and within subjects, respectively. Operator performance was evaluated in terms of time-to-task completion, workload, and situation awareness. Results demonstrated vocal cues to be superior to simple visual icons and no cueing for performance. Earcons did not produce worse performance ratings than vocal cues for complex messages. The results of this study are applicable to the design of future automated systems.

Effects of Robot Control Mode on Situation Awareness and Performance in a Navigation Task

Our ability to complete tasks in remote environments has improved with increased sophistication of robotic systems. The quality of remote task performance is driven by the quality of human interaction with robots which can be dependent upon the operator's ability to acquire situation awareness (SA) for task completion. There are, however, often critical limitations in development of SA, which are projected to have a magnified effect when operators must task and control multiple unmanned systems. In this study, we investigated the effects the mode of robot control on operator performance and ability to develop SA while navigating two robots through two mazes. Participants were randomly assigned to groups to control the robots in serial (one after another) or in parallel (at the same time) either manually or using two types of automation. The participants also viewed a systems interface to monitor the status of the robots. Results indicate that participants under serial control produced higher SA scores, though not significantly different from SA scores observed under parallel control modes. The best navigation performance was observed under parallel control with a high level of autonomy that followed a prescribed set of navigation rules. This control mode also resulted in the lowest workload scores. Participants were better able to correctly respond to SA queries for lower level, perceptual items in the robotics task as compared to higher level comprehension and projection items. Performance in the monitoring task was found to be significantly, positively correlated to participant SA.

Computer Vision for Space Robotics: Applications, Role and Performance

Space robotic systems reduce the time astronauts must spend in hazardous environments and endow them with additional capabilities in perception, task planning and execution, information storage and retrieval. Physical separation between an operator and a robot requires a certain degree of robot autonomy. Computer vision can provide necessary information about the state of the environment needed for semi- and fully autonomous operations. In this paper we review emerging applications of space robotics, discuss different robot control modes and the role played by computer vision. We identify typical operating conditions, present expected performance and discuss necessary conditions for acceptance of computer vision in space applications.