Enhancing Pilot Performance with a SymBodic
System
Walter Karlen*, Member, IEEE, Sylvain Cardin, Daniel Thalmann, Dario Floreano, Senior Member, IEEE
Abstract—Increased fatigue of pilots during long flights can
place both humans and machine at high risk. In this paper,
we describe our research on a SymBodic (SYMbiotic BODies)
system designed to minimize pilot fatigue in a simulated 48 hour
mission. The system detected the pilot’s sleep breaks and used this
information to plan future sleep breaks. When fatigue could not
be prevented, the SymBodic system assisted the pilot by providing
relevant flight information through a vibro-tactile vest. Experi-
ments showed that it was difficult for the pilot to adapt to the
suggested sleep schedule within the duration of the experiment,
and fatigue was not avoided. However, during periods of severe
sleep deprivation, the SymBodic system significantly improved
piloting performance.
Index Terms—human performance, fatigue management, hap-
tic feedback, sleep / wake classification, symbodic, aerospace
I. INTRODUCTION
Solar Impulse is an ambitious project to fly around the
world with a solar powered airplane [1]. The project aims to
prove the concept of flying over long distances with renewable
energies only. Until now, no manned solar powered airplane
was able to fly over night. To meet this challenge, a single-
pilot, solar powered glider with a wingspan of 63 meters of and
a weight of 1500 kg has been developed. The cruising speed
has been set to 25 knots. The lack of sleep during a long term
flight and the high cognitive demands will increase the pilot’s
fatigue over time. This is a very challenging environment for
the human body and a major question must be raised: How
can a human maintain high performance during a sustained
flight of multiple days?
In order to minimize pilot’s fatigue and to assist in moments
of fatigue we introduce here the concept of a SymBodic pilot
assistance system. A SymBodic system (SYMbiotic BODies)
is a wearable device that supports symbiotic communication
between the bodies of the human and of the machine in order
to improve feeling, monitoring and control. The developed
SymBodic system analyzes relevant body variables of the pilot
(heart rate, respiration) in order to provide a dynamically up-
dated physiological profile to the machine and pilot himself. It
also analyzes, summarizes, and conveys information from key
parts of the machine to the pilot in an ergonomic fashion. The
SymBodic device is designed to improve the pilot’s perception
of the machine and to allow the machine to activate alert
W. Karlen is with the Electrical and Computer Engineering in Medicine
group (ECEM), University of British Columbia (UBC), Vancouver, BC V6T
1Z4, Canada; *Corresponding author, e-mail: walter.karlen@ieee.org
D. Floreano is with the Laboratory of Intelligent Systems (LIS), Ecole
Polytechnique Fe´de´rale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
S. Cardin and D. Thalman are with the Virtual Reality Lab (VRLAB), Ecole
Polytechnique Fe´de´rale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
signals if the pilot sleeps or takes the machine outside safety
limits. By suggesting the pilot to sleep in time slots that fit a
polyphasic sleep schedule [2] and waking him up accordingly,
we expect to be able to minimize total sleep duration, reduce
the pilot’s overall fatigue, avoid severe sleep inertia [3]. By
additionally assisting the pilot with a vibro-tactile vest that
provides augmented information about the plane’s state we
expect to increase the pilot’s overall performance.
II. STATE OF THE ART
A. Sleep management in sustained operations
Stampi [4] summarized different strategies for sleep man-
agement during continuous work as: 1) Storing sleep in ad-
vance; 2) Enhancing the restorative sleep value; 3) Continuous
5 hour sleep; 4) Anchor sleep; 5) Extending wakefulness with
pharmacological agents; 6) Irregular napping; and 7) Polypha-
sic ultrashort sleep. Methods 1 to 4 are not appropriate for
long term piloting tasks and the use of pharmacological agents
is not desired. Irregular napping during short breaks is the
most common way to address sleep loss in continuous work
situations. However, it is not guaranteed that enough sleep can
be accumulated [4]. There is evidence that dividing the waking
day into several regular occurrences of short naps can reduce
the wake intervals and the total needed sleep time without
effects of sleep deprivation (polyphasic ultrashort sleep) [2].
This sleep-wake behavior is dominant in most animals and is
also present during the early development of humans [4]. For
these reasons we have chosen to implement a polyphasic sleep
schedule planner into the SymBodic system.
B. Sleep/wake detection
Traditionally, the states of sleep and wake are classified
using the analysis of brain wave patterns (EEG) [5]. Several
research groups demonstrated the use of EEG signals for
drowsiness detection of drivers [6]. The acquisition of EEG
signals shows a major inconvenience: Several electrodes needs
to be glued to the scalp and the corresponding wiring to the
recording system makes it very cumbersome for a pilot. There
is also a high susceptibility to different sources of noise.
Another commonly used technique for sleep/wake discrim-
ination is actigraphy [7]. In actigraphy, the acceleration of the
wrist of the subject is recorded and phases of low activity are
classified as sleep. However, it is difficult to derive a reliable
sleep prediction from the actigraphy signal. As consequence,
activities characterized by low levels of motion, to which the
pilot will be frequently exposed, are often misclassified as
sleep [8].
32nd Annual International Conference of the IEEE EMBS
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