Demo Reception

UIST'18 Adjunct, October 14–17, 2018, Berlin, Germany

Artificial Motion Guidance: an Intuitive Device based on
Pneumatic Gel Muscle (PGM)
Takashi Goto
Keio University
Yokohama, Japan
takashi.goto@kmd.keio.ac.jp

Swagata Das
Hiroshima University
Hiroshima, Japanswagatadas@hiroshima-u.ac.jp

Yuichi Kurita
Hiroshima University
Hiroshima, Japanykurita@hiroshima-u.ac.jp

Kai Kunze
Keio University
Yokohama, Japan
kai@kmd.keio.ac.jp

ABSTRACT

We present a wearable soft exoskeleton sleeve based on PGM.
The sleeve consists of 4 PGMs controlled by a computing
system and can actuate 4 different movements (wrist extension,flexion, pronation and supination). Depending on how strong
the actuation is, the user feels a slight force (haptic feedback)or the hand moves (if the users relaxes the muscles). The paper
gives details about the system implementation, the interaction
space and some ideas about application scenarios.
Author Keywords

Haptics and Haptic Interfaces,Wearable Devices, Pneumatic
Artificial Muscles (PAMs)
INTRODUCTION

There is an increased interest in the HCI research community
towards haptic/muscle interactions and interfaces, as they canprovide "eyes-free" means of receiving information. There
are several related works with regards to tactile feedback techniques. Kon et al. showed walking navigation that does not
require explicit interpretation by mean of Hanger Reflex [4].
Chen et al. showed motion guidance by means of external artificial muscle that mainly consists of stepper motors and elastic
band [1]. Electrical Muscle Stimulation (EMS) has been also
applied to create simple display that provide information byfeeling the pose of user’s muscle. Lopes et al. developed aninteractive system based on EMS that allows object to communicate their use by means of actuating user’s muscle (e.g.,a spray can, by itself, show the user that shaking is mandatory
before spraying) [5]. However, EMS is often difficult to handle as it requires to find the right muscles, one has to overcome
the impedance of the skin and for some body locations it’s notPermission to make digital or hard copies of part or all of this work for personal orclassroom use is granted without fee provided that copies are not made or distributedfor profit or commercial advantage and that copies bear this notice and the full citationon the first page. Copyrights for third-party components of this work must be honored.
For all other uses, contact the owner/author(s).

Figure 1: The Artificial Muscle sleeve is a soft exoskeleton
that enables the user to obtain information or skill throughtheir body. In assisting navigation scenarios, users can feel aslight drag towards the direction he/she is suppose to take.
save to apply an electrical current. In contrast we are using
Pneumatic Gel Muscle (PGM). These are pneumatic "tubes"
that can be activated by fairly low air pressure compared to theconventional Pneumatic Artificial Muscle (PAM) [6]. PAM
are often used in rehabilitation and assistive applications andPGM is also already proposed for these purposes. Yet, we focus on potential interaction caused by actuating human muscle
by means of PGM.
We actuate arm movement and provide tactile feedback using
our PGM sleeve system. We also introduce several use cases
for enhancing human motion in sport and assisting navigation.
In this work, we introduce an Artificial Muscle sleeve, a device
consisting of four PGM. We designed the Artificial Muscle
sleeve fitting a wearable form factor. The Artificial Muscle
sleeve can actuate the human hand easily (4 movements) andthere is no risk of injury as PGM is very flexible (also compared to rigid exoskeletons).

UIST’18 Adjunct, October 14–17, 2018, Berlin, Germany

INTERACTIVE SYSTEMS BASED ON PGM© 2018 Copyright held by the owner/author(s).

PAM is a conventional type of actuator that operates by compressed air, for example the systems used by McKibben ac-ACM ISBN 978-1-4503-5949-8/18/10.
DOI: https://doi.org/10.1145/3266037.3271644

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Demo Reception

UIST'18 Adjunct, October 14–17, 2018, Berlin, Germany

Each Artificial muscle is actuated by CO2 gas from a gas cylinder and the amount of gas is adjusted by a pressure regulator.
The PGM is either actuated or deflated through a solenoid
valve, which normally closed configuration. An Arduino Uno
sends the signal to actuate the solenoid valves. The system isstand-alone and can be controlled just by the Arduino.
For the demo interactions, we prepare a sleeve and the usercan wear it and experience the different actuation types. We
can extend, flex, pronate and supinate the users wrist if themuscles are activated strongly. However, we can also give justa slight "dragging"/"pulling" feeling (haptic feedback) if themuscles are only activated softly (with less air pressure).
APPLICATION SCENARIOSIn the following we describe a couple of application scenario
ideas.
Figure 2: The device based on PGM attached around user’s
forehand and it can actuate human arm for extension, flexion,pronation, supination. If the solenoid valve for each artificial
muscle open, the device show the specific movement for theuser.
tuator require high pressure to actuate while also requiring apower source, i.e., an air compressors which are costly andnot practical for users to wear [2]. PGM overcomes this limitation as it can be actuated at a lower pressure of approximately 20KPa compared to conventional artificial muscle.
Compared to rigid exoskeletons, our artificial muscle is foundto be easier to wear and integrate into a wearable form factor.
Researchers use PGM to build assistive suits to support the elderly or enhance human motion in sport. For example, Ogawa
et al. developed an assistive suit to enhance the walking gait
experience [6]. Das et al. provide force-feedback by meansof PGM [3]. Force Hand Grove is enabled with pneumatic
actuators and stretch sensors which support the user in performing wrist flexion, extension, pronation, and supination.
The work focuses on assistive applications our system is animprovement of the work from Das et al. , making the system
wearable and supporting all hand movements at the same time.
We demonstrate two application scenarios for our interactive
system based on PGM: enhancing human motion in sport andassisting navigation. These prototypes focus on two particular
benefits of PGM: (1) strong driving force without high electricity consumption, which enables easy actuation of the user’s
muscle in mobile scenario; and, (2) lightweight and flexibility
to ensure zero restriction of the user’s motion, yet does not
sacrifice a wearable form-factor.
SYSTEM & IMPLEMENTATION

A system schematic is shown in Figure 2. The sleeve consistsof 4 artificial muscles (from Daiya Industry Co. Ltd., Japan).
Two 20cm artificial muscles are used for wrist extension andflexion, whereas two 30cm artificial muscles are used for wrist
pronation and supination. Artificial muscle for extension andflexion were attached along the user’s arm and artificial muscle
for pronation and supination wrapped around the forearm ineach direction of actuating.

183

Enhancing Human Motion in sport. We already mentionedthat PGM is useful for sport application. Sakoda et al. alreadywork on improving the baseball swing [8]. In this paper, theswing timing is detects automatically and supports the swing
posture by shrinking the PGM. Although this system only
focus on supporting sport by fixing human posture, PGM
could be useful to teach specific motion, for example, how
to smash a ball in tennis because PGM could be helpful tocalibrate human posture directly.
Assisting Navigation. There is a several idea for assistingnavigation. Although navigation information is often provided
on a visual display or descriptive audio, the assisting navigation based on tactile feedback is also proposed [9, 7, 4].
The artificial muscle could be helpful on assisting navigation
scenarios and it indicates which direction you should go byactuating your arm. The user can feel a slight drag to the left
in their arm if they are supposed to take a left turn.
CONCLUSION

We present an initial implementation of an artificial muscle
sleeve based on PGM. In demonstration, we will show theArtificial Muscle sleeve, which can actuate the user’s forearm
like extension, flexion, pronation, supination. The system caneither actuate the 4 different wrist movement or give hapticfeedback in the 4 directions. Users can experience these in
the demonstration. We present two application scenarios here,
enhancing motion in sport and assisting navigation, yet we areinterested in what kind of application scenarios demo users
will come up with. In this paper, we mentioned only twoapplication scenarios, however there are potential interaction
because of the feature of PGM that enable to actuate humanmuscle directly. We plan to further improve the developmentof the suit as a wearable device and combine it with tracking
techniques for more practical application, so that we can more
get seamlessly information through our body.
ACKNOWLEDGMENTS

We thank the participants of our study. Acknowledgements arealso given to DAIYA Industry for providing components andsupport. We also thank Pedro Lopes for his advice. We further
acknowledge the financed support by JST(Presto), Grant No:
JP-MJPR16D3 and MJPR16D4.

Demo Reception

UIST'18 Adjunct, October 14–17, 2018, Berlin, Germany

REFERENCES

on Human Factors in Computing Systems. ACM,2515–2524.

1. Chia-Yu Chen, Yen-Yu Chen, Yi-Ju Chung, andNeng-Hao Yu. 2016. Motion guidance sleeve: Guiding
the forearm rotation through external artificial muscles.
In Proceedings of the 2016 CHI Conference on Human
Factors in Computing Systems. ACM, 3272–3276.

6. Kazunori Ogawa, Chetan Thakur, Tomohiro Ikeda,
Toshio Tsuji, and Yuichi Kurita. 2017. Development of apneumatic artificial muscle driven by low pressure and its
application to the unplugged powered suit. Advanced
Robotics 31, 21 (2017), 1135–1143.

2. Frank Daerden and Dirk Lefeber. 2002. Pneumatic
artificial muscles: actuators for robotics and automation.
European journal of mechanical and environmental
engineering 47, 1 (2002), 11–21.

7. Sonja Rümelin, Enrico Rukzio, and Robert Hardy. 2011.
NaviRadar: a novel tactile information display forpedestrian navigation. In Proceedings of the 24th annual
ACM symposium on User interface software andtechnology. ACM, 293–302.

3. Swagata Das, Yusuke Kishishita, Toshio Tsuji, Cassie
Lowell, Kazunori Ogawa, and Yuichi Kurita. 2018.
ForceHand glove: a wearable force-feedback glove withpneumatic artificial muscles (PAMs). IEEE Robotics andAutomation Letters 3, 3 (2018), 2416–2423.

8. Watura Sakoda, Antonio Vega Ramirez, Kazunori Ogawa,Toshio Tsuji, and Yuichi Kurita. 2018. Reinforced Suit
Using Low Pressure Driven Artificial Muscles For
Baseball Bat Swing. In Proceedings of the 9th Augmented
Human International Conference. ACM, 30.

4. Yuki Kon, Takuto Nakamura, Michi Sato, and Hiroyuki
Kajimoto. 2016. Effect of hanger reflex on walking. In
Haptics Symposium (HAPTICS), 2016 IEEE. IEEE,
313–318.

9. Emi Tamaki, Takashi Miyaki, and Jun Rekimoto. 2010.
PossessedHand: a hand gesture manipulation systemusing electrical stimuli. In Proceedings of the 1stAugmented Human International Conference. ACM, 2.

5. Pedro Lopes, Patrik Jonell, and Patrick Baudisch. 2015.
Affordance++: allowing objects to communicate dynamicuse. In Proceedings of the 33rd Annual ACM Conference184