IEEE Robotics & Automation Magazine - June 2019 - 27

presence of a real partner. This is of particular importance
when treating children because it can encourage more direct
involvement not only in the game but also in the activity.
However, there is no commercial, autonomous robot that
incorporates the benefits of HRI in terms of the degree of
acceptance required as part of therapy or the possibility of
customizing and training specific abilities for rehabilitation at
the motor and cognitive levels.
Previous Evaluations
Our system, NT, proposes a general framework for hands-off
robotic rehabilitation. It is the result of a new development
phase produced by the Therapist Project [34], the goal of
which is to design and develop an autonomous robotic prototype that supports rehabilitation in children with OBPP and
infantile CP (ICP). The current system incorporates an NAO
robot as the social interactive entity and an RGB-D sensor
that monitors users' movements.
NAO is a programmable social humanoid robot developed by Aldebaran Robotics, recently rebranded as SoftBank
Robotics [43]. The robot is 58 cm high and weighs 5.5 kg. It
has 5 DoF in each arm and a total of 25 throughout its body.
This robot also offers a complete set of sensors, cameras, and
microphones, which enhance its autonomous capability, and
interactive mechanisms that facilitate social interaction with
people. Figure 2 shows an OBPP patient playing the imitation
game with this robot during one of our previous evaluations.
The NT platform was initially evaluated in two phases
[33]: the first phase was carried out with 117 normally developing children to measure their degree of interaction and
improve the autonomy of the prototype in accordance with
the ongoing requirements [44]. Without any prior instructions, normally developing children were able to follow the
session and mostly viewed the robot as a social entity that was
actively engaged throughout the activity. Following that, during the second phase, three pediatric patients [45] from
VRUH had their first interactive experience with the NAO
robot and shared their impressions of the NT prototype's usefulness. The patients enjoyed the activity and were eager to
participate in future evaluations.
During both phases, participants were able to follow the
sessions with instructions from the robot (see Figure 2).
Achieving robot autonomy is an important objective; therefore,
having the robot make its own decisions improves the perception of the robot as a social entity, which may foster improved
patient engagement. We wanted patients to feel comfortable, so
we gave them a set of verbal and visual cues. We also realized
the need for a reward system that offers positive reinforcement
to the patient for every well-done exercise; this would later be a
key factor in maintaining patient engagement with the treatment. Using past experiences as a guide, we incorporated all
these elements into improving NT's architecture [35].
Objectives
After initial evaluations, the next step is to use the developed
technology in a long-term study. This work provides new

results from a four-month evaluation of our SAR platform
with pediatric patients at VRUH. The key points to be evaluated are
1) demonstrating the feasibility of using the NT robotic platform in a clinical setting during long-term exposure
2) removing the presence of the robotic engineer during the
sessions (to do so, the therapist must be trained to use the
tool, and the system must be sufficiently robust) and
3) obtaining feedback related to the acceptance of and satisfaction with the technology for both patients and their relatives, which will help improve the system.
Additionally, clinical results, which are preliminary due to the
short time frame of the study and the long-term progressive
nature of these pathologies, are of interest.
Methods
This section provides a brief description of how the NT system works: i.e., the robotic platform, detection of the users'
motion, and the two games involved in this study. It concludes with an explanation of the long-term evaluation procedure: i.e., the experimental setup at VRUH, the study
protocol, the study variables, and the instruments used for
both clinical and usability assessments.
Platform Description
NT is a cognitive software architecture that uses a socially
assistive robot with enough autonomy to carry out interactive
rehabilitation sessions. The executed robot actions are coherent with the perceived environment and meet the session's
requirements. This study involves two games: mirror and
Simon, which are described in a later section. Both were
designed by health-care professionals involved in the rehabilitation of these patients. During the sessions, the robot performs a set of prescribed poses, which the patient imitates. To
do so, the robotic platform is supported by an RGB-D sensor
that allows for checking of the patient's pose. The robot provides visual and verbal cues that help patients correct their
posture. The system also incorporates positive reinforcement
to reward patients with dances and animations after every
well-executed exercise.

Figure 2. An OBPP patient plays the imitation game (mirror) with
our NAO robot during a trial at VRUH, Sevilla, Spain.

JUNE 2019

IEEE ROBOTICS & AUTOMATION MAGAZINE

IEEE Robotics & Automation Magazine - June 2019

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