2020 International Conference on Computational Science and Computational Intelligence (CSCI)

Design of the Keyboard for the Heterophony Digital Piano

1st Yeonjeong Ji 2nd Younghyung Kim 3rd Sangin Do Kumoh National Institute of Kumoh National Institute of Dynatone, Technology, Technology, GUMI, Republic of Korea GUMI, Republic of Korea GUMI, Republic of Korea [email protected] [email protected] [email protected]

Abstract—Heterophony is the playing of the same melody in Korea, which is well equipped with various IT infrastructures, more than one way at the same time. In this paper, By improving is required to strategically foster the next-generation intelligent the sensitivity and touch of the keyboard, which is a representative instrument industry using future technologies such as IoT and input device (generating performance data) of a digital musical artificial intelligence, and secure smart instrument leading instrument and a key part of a piano, we proceed with the initial technology for this. design of parts to realize the emotional expression of an oriental musical instrument composed of heterophony, assemble, generate tolerances. Introducing the Smart Keyboard Module as an input Musical performance is important to experience of music and device capable of expressing emotions of various musical to apply creativity of musicians. The digital piano was instruments around the world by continuously modifying the part developed for performances in every instrument, and especially of the machine sound generation. in the piano.

Keywords— Digital Piano, Heterophony Keyboard, Intelligent, In the performer's preferences, the haptic signal and the effects Hammer Shank of vibrations is studied[1]. The digital piano is modified to the addition of vibrotactile feedback for performer's preferences. I. INTRODUCTION The force transducers is equipped in the flagship digital piano The advent of the 1 person 1 musical instrument era and the for body vibratioin[2]. The piano timbre nuances has been sensibility education craze, so in the midst of growing demand studied and the technique of this production is generally for musical instruments, the market share of digital musical depended on abstraction, conception, imitation and aural instruments that are relatively inexpensive and possess various modeling[3]. A research investigates computational approaches functions is increasing. The digital musical instrument global to formalise and model for music performance by performance market is expected to expand thanks to the development of data acquired[4]. In producing different timbral nuances, the digital media and increasing demand in developing countries precise performance features are extracted and identified from centered on China. Musical instruments are evolving into smart the data of high-accuracy sensors[5]. instruments beyond digital instruments with the recent acceleration of the Fourth Industrial Revolution. This paper design a keyboard that enriches the expression of the physical playing feeling and implements the intelligent sound source variation (heterophony) function linked to the smart platform.This is to improve the sensitivity and touch of the keyboard, which is a representative input device for digital instruments and a key component of the piano. Chapter 2 describes the general concept, and Chapter 3 describes the design of the improved system in each part. Chapter 4 concluded this.

II. HETEROPHONY CONCEPT A digital instrument is literally a type of instrument that makes sounds by electronic signals. The keyboard of digital instruments is a key component of the parts sector in the digital instrument cluster business, and is the foremost factor that determines the performance of the combined interest instrument G of about 400 parts. In addition, heterophony is a way of playing Fig. 1. Conceptual diagram of digital instruments based on smart platform the same melody in more than one way at the same time, and it

978-1-7281-7624-6/20/$31.00 ©2020 IEEE 1411 DOI 10.1109/CSCI51800.2020.00262 is a way to form a polyphonic texture(sound Configuration development of the Under-Key and the change of the assembly Principle) in music. Unlike polyphony in the narrow meaning of position of the Top/Under Key. simultaneously allocating to the plural part, it is a term referring to an ensemble method in which basically a group of variations Through the change of the lower core, the position variable of the same or similar melody are simultaneously heard. technology of the Under-Key was developed, and the variable position of the assembly position of the Top/Under Key gave the III. HETEROPHONY KEYBOARD MODULE DESIGN difference in the weight. Thus, the design of the 88 keyboards with fine weight differences is completed. Develop smart keyboard modules that can express various musical instruments and emotions of the world music DB through analysis of structure and behavior of grand action devices on acoustic keyboards. Develop a module process that produces I/O data on the input device by printing Signal Data relative to the input value of Direct Raw Data. Design the physical input drive through analysis of Capstan Block, Wippen device, and Repetition lever structure, and develop by applying the structure of Grand Action device. Designed with a structure that analyzes the operation movement of the internal mechanism of the Jack Part and Knuckle Roller and calculates the artificial data value, and implements the movement of the Hammer Shank and Head part, and outputs the value to correct the touch feeling data, and develop a smart instrument keyboard module that transmits system control raw data to the platform.

G

Fig. 4. Graded KeyCap Parts

A key element of the keyboard's hitting function is the high- restore power in Rubber. In order to accurately express Velocity's value in the multi-base high-speed performance of 256Poly's simultaneous sound software specification, we developed a rubber that can be used for similar number of times as acoustic piano by strengthening the existing Rubber's high- restore power.

Fig. 2. Conceptual diagram of digital instruments based on smart platform

G

Fig. 5. High-Restore Power Rubber Design Plot(Flank, Front)

The development part of +a interface in the existing three- Fig. 3. Conceptual diagram of digital instruments based on smart platform interface, is one of the key technologies in the Heteropony keyboard.

The development of special contact sensor, which gives the While the touch of the 1st to 88th keyboard is different in the input value of oriental sound source through various methods case of an acoustic piano, 88 KeyCap must be designed in the such as twisting, shaking, bending, and pressing continuously, same structure for mass production of parts. was completed. Design components such as sensor frame and check compatibility with design parts. The existing key touch sensation had the same disadvantage as the middle touch in the lower section, so the Graded KeyCap was developed to make a linear difference between touch sensations on the 1st to 88th keyboard through further

1412 In the case of semi-use materials, materials that are exposed to conditions such as salinity, moisture, and foreign substances of human fingers should be made of materials that are resistant to weather resistance.

In addition, the design requirements for visual and aesthetic factors require setting up a light reflective color space similar to ivory. As a material property, a material of chromacity corneinates similar to ivory was developed. G

Fig. 9. ivory chromacity coorninates value

IV. CONCLUSION In this paper, as a standard for maintaining acoustic keys and digital keys, the results of setting reference values for minimum G pronunciation conditions according to KeyCurve of Max Velocity 127 output and confirmation of touch and feel were Fig. 6. Design of Heterophony Sensor confirmed.

The design condition of the material parts and sensors that The initial design of the components for the emotional make up the Heterophony keyboards was to through a expression of the oriental musical instruments consisting of consumer's direct input the weatherproof/intolerant/accelerated heterophony is carried out. Develop smart keyboard modules as experimental conditions of white and black keyboards, it was input devices that can express emotions for various instruments decided to maintain part design standards for volumetric around the world by continuously modifying assembly of parts, changes(bending, warping, deformation, twisting). tolerance generation, and mechanical sound generation. In the case of White / Black Key, which is designed as a ACKNOWLEDGMENT piano keyboard, the touch pressure to the Z axis is generated by This study is the result of support as part of the project R&D the player's direct touch, and the material's molding criteria is project support project organized by the Korea Industrial developed to minimize the shrinkage and warpage of the part Complex Corporation.. concerned. REFERENCES

[1] F. Fontana, F. Avanzini, H. Jarvelainen, and S. Papetti, “Perception of interactive vibrotactile cues on the acoustic grand and upright piano”, Proc. Int. Conf. on Sound and Music Computing (SMC2014), Athens, Greece, pp. 948–953. Fig. 7. Smart instrument keyboard module expected CAD drawing [2] E. Guizzo, "Keyboard maestro", IEEE Spectrum, vol. 47, no. 2, 2010, pp. 32-33. [3] R. Woody, “The relationship between explicit planning and expressive performance of dynamic variations in an aural modeling task,” Journal of Research iin Music Education, vol. 47, no. 4, 1999, pp. 331-342. [4] W. Goebl, S. Dixon, G. DePoli, A. Friberg, R. Bresin, and G. Widmer, “‘Sense’ in expressive music performance: Data acquisition, computational studies, and models,” Sound to Sens - Sense to Sound: A State of the Art in Sound and Music Computing, P. Polotti and D. Rocchesso, Eds. Berlin, Germany: Logos, 2008, pp. 195-242. [5] M. Bernays, and C. Traube, "Expressive production of piano timbre: Touch and playing techniques for timbre control in piano performance," Cound and Music Computing Conference (SMC2013), Stockholm, Sweden, Aug. 2013.

Fig. 8. Design of heterophony keyboard

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