3D gaze cursor: continuous calibration and end-point grasp control of robotic actuators

© 2016 IEEE.Eye movements are closely related to motor actions, and hence can be used to infer motor intentions. Additionally, eye movements are in some cases the only means of communication and interaction with the environment for paralysed and impaired patients with severe motor deficiencies. Despite this, eye-tracking technology still has a very limited use as a human-robot control interface and its applicability is highly restricted to 2D simple tasks that operate on screen based interfaces and do not suffice for natural physical interaction with the environment. We propose that decoding the gaze position in 3D space rather than in 2D results into a much richer spatial cursor signal that allows users to perform everyday tasks such as grasping and moving objects via gaze-based robotic teleoperation. Eye tracking in 3D calibration is usually slow - we demonstrate here that by using a full 3D trajectory for system calibration generated by a robotic arm rather than a simple grid of discrete points, gaze calibration in the 3 dimensions can be successfully achieved in short time and with high accuracy. We perform the non-linear regression from eye-image to 3D-end point using Gaussian Process regressors, which allows us to handle uncertainty in end-point estimates gracefully. Our telerobotic system uses a multi-joint robot arm with a gripper and is integrated with our in-house GT3D binocular eye tracker. This prototype system has been evaluated and assessed in a test environment with 7 users, yielding gaze-estimation errors of less than 1cm in the horizontal, vertical and depth dimensions, and less than 2cm in the overall 3D Euclidean space. Users reported intuitive, low-cognitive load, control of the system right from their first trial and were straightaway able to simply look at an object and command through a wink to grasp this object with the robot gripper

A concept-environment for computer-based augmentative and alternative communication founded on a systematic review

Introduction: locked-In Syndrome is admittedly the worst case of motor and speech impairment, it seriously damages the ability of oral and gestural communication of patients. In recent years, alternative and augmentative communication technology has provided resources to restore these patients' ability to communicate. Methods: in order to relate and classify the main methods with that purpose, this work conducted a systematic review on several journal databases. Results: we found 203 related papers and 55 of them were selected to compose the study. After that, we classified them into three major groups and we identified the main difficulties when using each approach. Conclusion: in order to overcome these difficulties, we propose a new system concept to develop an adaptive, robust and low cost communication environment. The proposed system is composed of five modules: data entry, communication, aid to the caregiver and external interaction

The use of P300-based BCIs in amyotrophic lateral sclerosis : from augmentative and alternative communication to cognitive assessment

The use of augmentative and alternative communication (AAC) tools in patients with amyotrophic lateral sclerosis (ALS), as effective means to compensate for the progressive loss of verbal and gestural communication, has been deeply investigated in the recent literature. The development of advanced AAC systems, such as eye-tracking (ET) and brain-computer interface (BCI) devices, allowed to bypass the important motor difficulties present in ALS patients. In particular, BCIs could be used in moderate to severe stages of the disease, since they do not require preserved ocular-motor ability, which is necessary for ET applications. Furthermore, some studies have proved the reliability of BCIs, regardless of the severity of the disease and the level of physical decline. However, the use of BCI in ALS patients still shows some limitations, related to both technical and neuropsychological issues. In particular, a range of cognitive deficits in most ALS patients have been observed. At the moment, no effective verbal-motor free measures are available for the evaluation of ALS patients\u2019 cognitive integrity; BCIs could offer a new possibility to administer cognitive tasks without the need of verbal or motor responses, as highlighted by preliminary studies in this field. In this review, we outline the essential features of BCIs systems, considering advantages and challenges of these tools with regard to ALS patients and the main applications developed in this field. We then outline the main findings with regard to cognitive deficits observed in ALS and some preliminary attempts to evaluate them by means of BCIs. The definition of specific cognitive profiles could help to draw flexible approaches tailored on patients\u2019 needs. It could improve BCIs efficacy and reduce patients\u2019 efforts. Finally, we handle the open question, represented by the use of BCIs with totally locked in patients, who seem unable to reliably learn to use such tool

The combined use of Brain Computer Interface and Eye-Tracking technology for cognitive assessment in Amyotrophic Lateral Sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease. Cognitive deficits are known to be present in some ALS patients. Recently, it has been hypothesized that most ALS patients show cognitive impairments of one sort or the other. In this study we explore the capability of a combined use of Brain Computer Interface and Eye-Tracking technology to assess such deficits and as augmentative and alternative communication tools. In particular, we propose a setup based on both technologies in order to realize a neuropsychological battery for cognitive assessment in ALS