The Biomechanics of Character Types in Javanese Dance
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The Biomechanics of Character Types in Javanese Dance Luis Hernandez-Barraza, PhD, Chen-Hua Yeow, PhD, and Miguel Escobar Varela, PhD Abstract iomechanics is a technical the tool kit of biomechanics is perti- The aim of this study was to describe and discipline that explains body nent for generating greater knowledge compare the different character sub-types motion through physical con- of this fundamental human form of of Javanese dance from a biomechanical Bcepts including angles, moments, expression. Through the present study, perspective. One professional dancer was energy consumption, power, and we aim to contribute an analysis of Ja- asked to repeat a basic motion (standing- ground reaction forces,1-4 and its ap- vanese dance to the growing literature up) according to the movement rules plications encompass fields such as on the biomechanics of dance. that pertain to six character sub-types sports, rehabilitation, and the analysis Javanese dance has a long history; (humble-refined, proud-refined, humble- of daily activities. Recently, potential it is perhaps rooted in the shamanistic strong, proud-strong, monkey, and bird). A motion capture system consisting of applications have expanded to include dances of the pre-Hindu era, which seven infrared cameras with a sample the analysis of dance and other forms were further shaped by interaction rate of 100 Hz and two force plates with of artistic expression. These studies with Indian-influenced dance and a sample rate of 1,000 Hz were used to are usually aimed at improving teach- music during the Hindu-Buddhist capture kinematics and kinetics. There ing, skill enhancement, and injury period.12 However, classical dance were significant differences in the bio- prevention.3 developed more actively from the 18th mechanical values we calculated for each Although biomechanics has de- Century onward, partially due to the character sub-type: range of motion, an- monstrably increased dance knowl- patronage of the courts of east and gular velocity, and ground reaction forces. edge, only a handful of dance genres central Java.13 Dance is very common The refined sub-types (humble-refined have been analyzed from a biome- today in various settings, and one of and proud-refined) showed the lowest val- chanical perspective; most commonly the best known forms is Sendratari ues at the knee joint for range of motion 2,5-11 and the lowest ankle, shoulder, and wrist ballet, Irish dance, and flamenco. Ramayana (the dance we used for this angular velocities. This result suggests Hence, very little is known about the study), a form that developed in the that low values in these measurements great diversity of dances around the 1960s on the foundation of classical are related to the smooth movements of world from a biomechanical perspec- Javanese dance. refined sub-types. These measurements tive, even though dance constitutes In all forms of classical Javanese help describe and contrast the motion one of the oldest and most widespread dance, character types are important. patterns of Javanese dance, contributing forms of cultural expression and ex- Sometimes the audience might be both to the scientific analysis of Javanese hibits many differences across cultures unfamiliar with the specific narrative dance and the application of biomechan- and geographic locations. We believe being depicted, but they are still able ics to the study of dance more generally. to infer certain things about the story by paying attention to the character Luis Hernandez-Barraza, PhD, and Chen-Hua Yeow, PhD, Department of types presented. Character types are Biomedical Engineering, National University of Singapore and Advanced Robotics Center, National University of Singapore, Singapore. Miguel Escobar Varela, divided into three major groups: putri PhD, Department of English Language and Literature, National University of (female), alusan (masculine-refined), Singapore, Singapore. and gagahan (masculine-strong). There are many sub-divisions of these Correspondence: Miguel Escobar Varela, PhD, Department of English Language major types, depending on the specific and Literature, National University of Singapore, Block AS5, 7 Arts Link Singapore kind of dance depicted. The character 117570, Singapore; [email protected]. types are identified by their makeup Copyright © 2019 J. Michael Ryan Publishing, Inc. 104 https://doi.org/10.12678/1089-313X.23.3.104 Journal of Dance Medicine & Science • Volume 23, Number 3, 2019 105 and costume, but also by the kind of movement that is common for each character type. For example, refined sub-types are said to have relatively smooth and less angular motions. Although qualitative descriptions and notations are available14 the biomechanical analysis of character sub-types has not previously been attempted. In this study we focus on the following character sub-types, which are the ones used in Sendratari Ramayana (see Figs. 1 through 6 for the starting and ending positions): Humble-refined (impur) and proud- Figure 1 Humble-refined: left, initial position; right, final position. refined (kagok-kinantang), which are derived from the refined (alu- san) type. Humble-strong (kambĕng) and proud-strong (kalang-kinantang), derived from the strong (gagahan) type. Animal sub-types, which are the monkey (kambĕng-dhĕngklik) and the bird (Jatayu). It should be noted that Jatayu is the proper name of a specific character, and thus we capitalize it in writing. There are certain motions that are specific to a single character type and some that are shared across characters. Figure 2 Proud-refined: left, initial position; right, final position. For this comparative biomechanical study we selected the jumĕnĕng mo- tion (where the character stands up from a kneeling position), since this motion is performed by all character sub-types. For consistency, we wanted a single dancer to perform all motions according to the different character sub-types. Male dancers learn to per- form all character sub-types as part of their training, but not the female character sub-types. The objectives of the study were: 1. to describe the motion patterns of the different character sub-types in terms of biomechanical parameters, and 2. Figure 3 Humble-strong: left, initial position; right, final position. to compare motion patterns across the character sub-types to identify differ- reaction forces (GRF) for anterior- extremity injuries that might affect ences between them. We hypothesized posterior, medio-lateral, and vertical the dance biomechanics was recruited that, compared to the strong and components; and 4. joint moments. from Java, Indonesia. His anthropo- animal sub-types, the refined sub-types metric data were recorded (Table 1) would exhibit lower values in all the Methods and he gave informed consent before following measurements: 1. range of Subject Recruitment and participation according to the uni- motion (ROM) for both lower and Preparation versity’s Institutional Review Board upper body; 2. angular velocities for the One professional male Javanese dancer guidelines. The dances are always upper and lower body joints; 3. ground with no history of upper and lower performed barefoot, and we kept this 106 Volume 23, Number 3, 2019 • Journal of Dance Medicine & Science plates (AMTI, Watertown, Massachu- setts, USA) were used to obtain GRF data at a sampling rate of 1,000Hz. The force plates were synchronized to the motion capture system, and both were calibrated according to the manufacturer’s recommendations be- fore the dance trials were conducted.15 Experimental Protocol The dancer was instructed to perform the jumĕnĕng (standing up motion) as it corresponds to the six different character sub-types described ear- Figure 4 Proud-strong: left, initial position; right, final position. lier. In the initial kneeling position (jĕnkĕng) the right knee is bent on the floor with the foot placed in a dorsiflexed position while the left knee is slightly flexed with the foot on the ground. Afterward, the dancer stands up, making a full extension of his right knee with the left knee in a slightly flexed position. Although the initial position of the lower limbs is roughly similar in all character sub-types, the final position varies in each case (Figs. 1 through 6). The dancer performed a total of three tri- als per character sub-type. After each performance the dancer was given 2 Figure 5 Monkey: left, initial position; right, final position. minutes of rest. Data Collection and Processing Vicon Nexus 1.8.5 and Polygon 3.5 software were used for data collec- tion and processing, respectively. The kinematic data were smoothed using a Woltring filter with a mean square error of 20 mm2.15-17 All kinetic (GRF and joint moments) and kinematic (joint angles and angular velocities) data were averaged among the three trials in each character sub-type set. The joints of interest for upper extremity were: shoulder, elbow, and wrist; and for lower extremity: Figure 6 Bird: left, initial position; right, final position. hip, knee, and ankle. The ROM was calculated from the difference be- condition in the study. Therefore, shoe employed to collect kinematic data at tween the joint angle at maximum variations do not affect the dancer’s a sample rate of 100 Hz. Forty-one extension and the joint at maximum performance, either in the experiment reflective markers (14 mm diameter) flexion for the sagittal plane. The joint or in real-life situations. placed by an experienced instructor angular velocities were calculated as were attached to the dancer following the first derivative of the joint angles Instrumentation the full body Plug-In-Gait Marker with respect to time in the sagittal A motion-capture system (Vicon MX, model (Vicon, Oxford Metrics, Ox- plane. Joints moments were obtained Oxford Metrics, Oxford, UK), con- ford, UK) to facilitate capture of the through use of the Vicon Polygon 3.5 sisting of seven infrared cameras, was dancer’s motion. Two embedded force software. Journal of Dance Medicine & Science • Volume 23, Number 3, 2019 107 Table 1 Anatomical Measurements of the Javanese Dancer often indicates differences among characters.