Haptic Marionette: Wrist Control Technology Combined withElectrical Muscle Stimulation and Hanger Reflex
Mose Sakashita

Yuta Sato

Ayaka Ebisu

University of Tsukuba
mose.sakashita@gmail.com

University of Tsukuba
s.yutassie@gmail.com

University of Tsukuba
twill.fig1125@gmail.com

Keisuke Kawahara

Satoshi Hashizume

Naoya Muramatsu

University of Tsukuba
kawahara@ai.iit.tsukuba.ac.jp

University of Tsukuba
pota1401@hotmail.co.jp

University of Tsukuba
sh.mn.nat@gmail.com

Yoichi Ochiai

University of Tsukuba
wizard@slis.tsukuba.ac.jp

Figure 1: Combination of EMS and Hanger Reflex (left), and application images using our system (center, right).

ABSTRACT
Many devices and systems that directly control a user’s hands havebeen proposed in previous studies. As a method for controllinga user’s wrist, Hanger Reflex and Electrical Muscle Stimulation
is often used. We propose a method combined Electrical muscle
stimulation and Hanger Reflex. We use Hanger Reflex to elicit thesupination and pronation, and EMS to cause the flexion and extension. We believe that the proposed method of this study contributes
to the exploration of new devices and applications on the fieldsof haptics, virtual and augmented reality, mobile and wearableinterfaces.

CCS CONCEPTS• Human-centered computing → Haptic devices;

KEYWORDSEMS, Hanger Reflex, Feedback
ACM Reference Format:
Mose Sakashita, Yuta Sato, Ayaka Ebisu, Keisuke Kawahara, Satoshi Hashizume,
Naoya Muramatsu, and Yoichi Ochiai. 2017. Haptic Marionette: Wrist Control Technology Combined with Electrical Muscle Stimulation and Hanger
SA ’17 Posters, November 27-30, 2017, Bangkok, Thailand© 2017 Copyright held by the owner/author(s).
This is the author’s version of the work. It is posted here for your personal use. Notfor redistribution. The definitive Version of Record was published in Proceedings of SA’17 Posters, https://doi.org/10.1145/3145690.3145743.

Reflex. In Proceedings of SA ’17 Posters. ACM, New York, NY, USA, 2 pages.
https://doi.org/10.1145/3145690.3145743

1INTRODUCTION

Many devices and systems that directly control a user’s hand havebeen proposed in previous studies. For example, they have been
proposed for playing an instrument, giving feedback, drawing andso on. As a method for controlling a user’s wrist, hanger reflex andelectrical muscle stimulation (EMS) is often used.
The hanger reflex is a phenomenon that causes force sensationand involuntary head rotation when the head is fastened with awire hanger. The similar phenomenon has been observed on thewrist as well, and it has been used to control the wrist. [Nakamuraet al. 2014] Hanger reflex can cause wrist supination and pronation.
Pronation of the wrist is a rotational movement where the hand andupper arm are turned inwards. Supination is the opposite movement
where the forearm or palm are rotated outwards. It means that
hanger reflex can realize control of the wrist on the roll axis.
On the other hand, EMS uses electrical impulses to elicit contraction on the muscle, and causes the involuntary contraction of theuser’s muscles. This technique has also been used for controllinguser’s hand. [Lopes et al. 2015], [Ebisu et al. 2017] EMS can control
the wrist on the pitch axis very accurately, since it is very effective
to stimulate muscle for causing Flexion and Extension.
However, both hanger reflex and EMS has limitation as a method
for controlling the wrist. In case of hanger reflex, it can control thewrist on the roll axis, but it is difficult to control on the pitch axis.

SA ’17 Posters, November 27-30, 2017, Bangkok, Thailand
Moreover, EMS is efficient in controlling the wrist on the pitch axis,
but not accurate on the roll axis, since the muscle for causing thewrist supination and pronation is too complex to stimulate innermuscles directly.
To address these problems, we propose a method combined electrical muscle stimulation and hanger reflex. (Figure 1 left) We use
Hanger Reflect to elicit the supination and pronation, and EMS tocause the flexion and extension. We confirmed that this system can
independently control the wrist on both roll and pitch axis. (Figure2)

Supination

Pronation

FlexionExtension

Figure 2: The proposed method combined EMS and Hanger
Reflex to control the wrist.

2IMPLEMENTATION

The proposed system includes two technologies; EMS, and Hanger
Reflex. Therefore, we implemented a different hardware for eachpart.

2.1

EMS for Flexion and Extension

The circuit that generates EMS applies voltage pulse into the muscles of a participant using 2 pairs of electrodes. The strength ofelectric muscle stimulation from the electrode is controlled independently by micro-controller (Arduino Mega) changing the impedanceof digital potentiometers (MCP4131). Each digital potentiometeris connected to micro-controller with SPI interface. The voltage ofEMS can be changed in the range of 0-50V.
The circuit generates EMS pulse, whose pattern is controlled by
the micro-controller (Arduino Uno). The waveform of EMS is set
as 40Hz periodic pulse signal with pulse-width of 200 µs.

2.2Hanger Reflex for Supination andPronation

We design wristband for invoking the hanger reflex, and output
it with a 3D printer. It is reported that the perceptual force fromthe hanger reflex is enhanced when a vibration is also presented.
[Nakamura et al. 2016] We attached vibrators to the wristband tochange the speed of wrist’s reaction computationally.

3APPLICATIONThe combined control method is applicable to medical rehabilitation, VR/AR entertainments, redirected walking [Ishii et al. 2016],and display of instructions. (Figure 3, Figure 1 center, right) In thefield of medical rehabilitation, a therapist can utilize the wrist control method to reactivate the patient’s muscles of the wrist that

M. Sakashita et al.

Figure 3: (right) feedback to a player using the system, (left)
practice of a rhythm pattern for musical performance.
have been affected during surgery and start to trigger the muscle
memory.
In addition, this technique has possibility to explore novel VR/AR
applications. In virtual games, user enjoy interactions with objects
and characters. The capability to control the user’s wrist allows
user to feel more immersive experience in a lot of interactions (eg.,shaking hands, touching objects, etc.).
This method can be also utilized to give users feedback of instructions when they use complicated products that are hard tounderstand how to use.

4CONCLUSION AND FUTURE WORKIn this paper, we proposed a novel method to control human handposture by combining conventional methods. We believe that theproposed method of this study contributes to the exploration ofnew devices and applications in the fields of haptics, virtual andaugmented reality, mobile and wearable interfaces. As future work,
this method still needs to be investigated in terms of the accuracyof angle control, and what interactions it can accomplish.

REFERENCES
Ayaka Ebisu, Satoshi Hashizume, Kenta Suzuki, Akira Ishii, Mose Sakashita, and YoichiOchiai. 2017. Stimulated Percussions: Method to Control Human for Learning
Music by Using Electrical Muscle Stimulation. In Proceedings of the 8th Augmented
Human International Conference (AH ’17). ACM, New York, NY, USA, Article 33,
5 pages. https://doi.org/10.1145/3041164.3041202
Akira Ishii, Ippei Suzuki, Shinji Sakamoto, Keita Kanai, Kazuki Takazawa, Hiraku Doi,and Yoichi Ochiai. 2016. Optical Marionette: Graphical Manipulation of Human’s
Walking Direction. In Proceedings of the 29th Annual Symposium on User Interface
Software and Technology (UIST ’16). ACM, New York, NY, USA, 705–716. https://doi.org/10.1145/2984511.2984545
Pedro Lopes, Alexandra Ion, Willi Müller, Daniel Hoffmann, Patrik Jonell, and Patrick
Baudisch. 2015. Proprioceptive Interaction. In Proceedings of the 33rd Annual ACM
Conference Extended Abstracts on Human Factors in Computing Systems (CHI EA’15). ACM, New York, NY, USA, 175–175. https://doi.org/10.1145/2702613.2732490
Takuto Nakamura, Narihiro Nishimura, Taku Hachisu, Michi Sato, Vibol Yem, andHiroyuki Kajimoto. 2016. Perceptual Force on the Wrist Under the Hanger Reflexand Vibration. In Proceedings, Part I, of the 10th International Conference on Haptics:
Perception, Devices, Control, and Applications - Volume 9774 (EuroHaptics 2016).
Springer-Verlag New York, Inc., New York, NY, USA, 462–471. https://doi.org/10.
1007/978-3-319-42321-0_43
T. Nakamura, N. Nishimura, M. Sato, and H. Kajimoto. 2014. Application of Hanger
Reflex to wrist and waist. In 2014 IEEE Virtual Reality (VR). 181–182. https://doi.
org/10.1109/VR.2014.6802111