Alejandro Clemotte

Assistive Robots for Physical and Cognitive Rehabilitation in Cerebral Palsy

Cerebral palsy (CP) is one of the most severe disabilities in childhood and makes heavy demands on health, educational, and social services as well as on families and children themselves. The most frequently cited definition of CP is a disorder of posture and movement due to a defect or lesion in the immature brain, [1].

Preliminary Result from a Multimodal Interface for Cerebral Palsy Users Based on Eye Tracking and Inertial Technology

Cerebral palsy (CP) is a disorder that arises in childhood and stays the rest of life. CP affects movement, posture and muscle tone. According ASPACE Confederation CP is a whole person disorder consisting of a permanent but not unchanging disorder of muscle tone, posture and movement due to a non-progressive lesion in the brain before the development and growth are complete”. CP generates constraints that affect motor control of traditional human-computer interfaces (HCI), reducing the opportunities for interaction. There are various solutions to access computer for people with disabilities. However, accessibility is compromised when the user suffers a severe motor impairment. This paper hypothesizes that the integration of HCI that use different technologies can facilitate access to the computer for people with severe neuro-motor limitations. Based on this hypothesis, we studied in a practical way, with people with CP, the features of two existing HCI: IRISCOM, an eye tracking interface and ENLAZA, a head motion tracking based on inertial technology. Several metrics will used to evaluate the usability of the IRISCOM system as input device for subjects with CP. The head posture will be analyzed using the ENLAZA interface in order to estimate its influence on the usability of the IRISCOM system.

Positive and Negative Motor Signs of Head Motion in Cerebral Palsy: Assessment of Impairment and Task Performance

This paper analyzes the presence of positive and negative motor signs in people with cerebral palsy (CP). Positive motor signs are those that lead to involuntarily increased frequency or magnitude of muscle activity. Negative motor signs describe insufficient muscle activity or insufficient control of muscle activity. In this paper, a head-mounted alternative computer interface based on inertial technology was used to assess motor signs in seven users with CP. Task performance and control of posture was related to the impairment. There are no significant differences between users with CP and healthy control participants in the frequency domain of the head movement. Results suggest that this kind of motor disorders is not related to positive motor signs. Moreover, a control mode based on posture more than on movements is not optimum; an alternative control mode must be specially designed for users with poor postural control.

Human-computer interaction for users with cerebral palsy based on head orientation. Can cursor’s movement be modeled by Fitts’s law?

Abstract This paper presents an experiment to validate a head-mounted inertial interface for human-computer interaction (HCI) developed for people with cerebral palsy (CP). The method is based on Fitts’s law, an empirical model of human motor performance for aimed movements. Head motion is recorded in a series of goal-crossing tasks and a regression model of the movement time ( MT ) is estimated for each user. Values of R 2 above 0.9 are indicators of a strong correlation of those motion patterns with the linear model proposed by Fitts. The analysis of MT confirmed that head movements of users without disability follow Fitts’s law and showed that 3 users with CP (MACS IV and V) had the same behavior. There was a weaker correlation ( R 2 =0.839) for one individual with cervical dystonia and ballistic movements and no correlation for two users with cervical hypotonia and dyskinetic CP. Results show the impact of ballistic movements and poor postural control in computer interaction. They also provide the foundation for new interaction techniques to develop a universal computer interface for motor impaired users.

Accuracy and Precision of the Tobii X2-30 Eye-tracking under Non Ideal Conditions

This document describes a methodology for the measurement of accuracy and precision of a remote eye tracker, the Tobii X2-30, under non ideal condition. The test was performed with 10 people. The results are: 2.46 and 1.91 degrees for the accuracy and precision respectively. The results can be used to establish the target size on the screen.

Metodología de Evaluación de Eye-trackers como Dispositivos de Acceso Alternativo para Personas con Parálisis Cerebral

Los autores agradecen a ATENPACE (Espana) y Colegio San Rafael (Espana) por su colaboracion, en especial a los participantes, sin ellos, este estudio no habria sido posible. A. Clemotte da las gracias a ITAIPU Binacional (Paraguay). Esta investigacion fue financiada por el Proyecto INTERPLAY (RTC-2014-1812-1) e INTERAAC (RTC-2015-4327-1).

BiMU—Inertial Sensors and Virtual Reality Games for the Rehabilitation of the Upper Limb in Cerebral Palsy

BiMU is a platform for computer access and rehabilitation of the upper limb through virtual reality (VR) games. It adapts to the motor and cognitive level of the user and its main goal is improving the efficiency of traditional therapies: reducing disability, increasing functional ability, and promoting social participation. BiMU’s peripheral consists of two wireless inertial measurement units that are attached to the forearm and upper arm and measure their movement. This information is used to control the movement of the cursor and perform click actions. In this paper, we present a pilot study that aimed to improve the quality of a specific movement: the forearm supination. The participants wore the BiMU system and played a series of VR games that recorded their performance. BiMU allows users computer access and a new mode of interactive occupational therapy. Moreover, it registers physical parameters and task performance measures that can be used by therapists to design customized rehabilitation protocols consisting of sequences of games to exercise specific functional movements and to monitor the evolution of the child throughout the work sessions.

A Novel Head Cursor Facilitation Technique for Cerebral Palsy: Functional and Clinical Implications

This work was possible thank to the projects NetMD (RTC-2015-3967-1), NeuroMOD (DPI2015-68664-C4-1-R), InterAAC (RTC-2015-4327-1), CP-Walker (DPI2012-39133-C03-03) and Interplay (RTC-2014-1812-1). The Spanish Ministry of Economy, Industry and Competitiveness financed all these projects.