Classical string instrument bow sensing system (CSB-SS) utilizing 3D structurally integrated force-sensitive resistors for enhanced player feedback

Abstract

A sensing system for classical string instrument bows includes a device body conforming to a bow's geometry and formed from a semi-rigid or elastic polymer. Three-dimensional structurally integrated force-sensitive resistors (3DSI-FSRs) are printed into or onto the device body at user touch locations to measure applied forces. A sensing module detects forces, bow orientation, and linear and rotational acceleration. A user feedback module may provide haptic vibrations, visual indicators through an LED array or LCD display, and wireless communication for transmitting data to an external device. A removable fastening mechanism may secure the device body to the bow. The system enhances player technique analysis, enables real-time feedback, and provides objective biomechanical data for training, injury prevention, and performance optimization.

Description

PCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCTCLASSICAL STRING INSTRUMENT BOW SENSING SYSTEM (CSB-SS) UTILIZING 3D STRUCTURALLY INTEGRATED FORCE-SENSITIVE RESISTORS FOR ENHANCED PLAYER FEEDBACKINVENTION PRIORITY

[0001] This patent application claims priority under the PCT (Patent Cooperation Treaty) to U.S. Provisional Patent Application Serial No. 63 / 722,533, entitled “CLASSICAL STRING INSTRUMENT BOW SENSING SYSTEM (CSB-SS) UTILIZING 3D STRUCTURALLY INTEGRATED FORCE-SENSITIVE RESISTORS FOR ENHANCED PLAYER FEEDBACK,” which was filed on November 19, 2024, and is incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] Embodiments are related to sensor devices and methods for configuring sensor devices. Embodiments further relate to structurally integrated force-sensitive resistors. Embodiments also relate to a classical string instrument bow sensing system (CSB-SS) utilizing 3D structurally integrated force-sensitive resistors for enhanced player feedback.BACKGROUND

[0003] A classical string instrument bow, typically used for instruments such as the violin, viola, cello, or double bass, is a finely crafted tool designed for both precision and durability. The bow is composed of several key components including a stick, a frog, hair, tip, wrap, and balance point.

[0004] The stick is the main body of the bow, traditionally made of Pernambuco wood for high-end bows, although other woods such as Brazilwood or synthetic materials like carbon fiber are also used in more affordable or modern bows. The stick is typically slightly curved, with the convex side facing toward the hair. The curvaturePCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT of the stick (referred to as the "camber") plays a crucial role in the bow’s response and flexibility.

[0005] The frog is the part of the bow that holds the horsehair and allows the player to grip and control the bow. It is usually made from ebony or a high-density synthetic material. The frog houses the thumb leather, a small patch that provides grip, and the screw mechanism which adjusts the tension of the hair. The frog’s design varies by instrument size and individual preference but typically has a slight curve for ergonomic handling.

[0006] The bow's horsehair (commonly from the tail of a horse) is stretched between the tip and the frog. The number of hairs can vary, but typically ranges from 150 to 200 strands. The hair is coated with rosin to increase friction between the bow and the strings, enabling the bow to produce sound. The tension of the hair is adjustable via the screw in the frog.

[0007] The tip of the bow is a small, often reinforced piece of material (often ivory, plastic, or other synthetic compounds) that protects the delicate end of the bow. The tip is where the bow encounters the string, and its design is crucial for control and sound quality.

[0008] The grip area of the bow is wrapped with a material such as leather or sometimes nylon, providing a tactile surface for the musician to hold the bow comfortably and securely. The balance point is a critical factor for the playability of the bow, as it determines how the bow feels in the player’s hand. Classical bows are generally balanced closer to the frog (especially for violin and viola), while some cello and bass bows may balance slightly more toward the middle or the tip. The placement of the balance point affects the ease with which a musician can execute various bowing techniques, such as staccato or legato. The weight length and shape of the bow vary based on the instrument.PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCTBRIEF SUMMARY

[0009] The following summary is provided to facilitate an understanding of some of the innovative features unique to the disclosed embodiments and is not intended to be a full description. A full appreciation of the various aspects of the embodiments disclosed herein can be gained by taking the entire specification, claims, drawings, and abstract as a whole.

[0010] The disclosed embodiments relate to a classical string instrument bow sensing system (CSB-SS) that integrates three-dimensional structurally integrated force-sensitive resistors (3DSI-FSRs) directly into a bow-conforming device body. The system enables multipoint force sensing at finger contact regions, allowing precise measurement of player-applied forces during bowing motions. An onboard sensing module may further detect attitude, orientation, linear acceleration, and rotational acceleration of the bow through a multi-axis inertial measurement unit.

[0011] It is, therefore, one aspect of the embodiments to provide for an improved sensor device and a method of manufacturing the sensor device.

[0012] It is another aspect of the embodiments to provide for a structurally integrated force-sensitive resistor.

[0013] It is a further aspect of the embodiments to provide for a classical string instrument bow sensing system (CSB-SS) that utilizes 3D structurally integrated forcesensitive resistors for enhanced player feedback.

[0014] The aforementioned aspects and other objectives and advantages can now be achieved as described herein.

[0015] In an embodiment, a sensing system for classical string instrument bows, can include a device body configured to conform to the shape and size of a bow for a classical string instrument, the device body configured from a semi-rigid or elastic polymer material. The system can further include a group of force-sensitive resistorsPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT structurally integrated into or onto the device body, the resistors comprising three- dimensional force-sensitive resistors (3D-FSRs) configured as a part of the device body. A sensing module can be configured to detect: orientation of the bow, linear and rotational acceleration of the bow, and forces applied at user touch points on the bow. A user feedback module can include a haptic feedback mechanism, a visual feedback system including at one or more of an LED array or an LCD screen, and a wireless communication interface for transmitting sensor data to an external device. The sensing system can further include a removable fastening mechanism for securing the device body to the bow.

[0016] The system optionally provides real-time user feedback through haptic vibration, LED or LCD visual indicators, and wireless telemetry via Bluetooth Low Energy. Certain embodiments include Hall-effect sensors positioned along the bow stick to identify string-contact position. The CSB-SS may be implemented as a removable or permanently integrated structure, with variations supporting different performance needs.

[0017] By structurally integrating sensing elements directly into the bow-mounted device body, the system enables high-resolution biomechanical measurement, real-time feedback, educational insight, injury-prevention analysis, and post-session performance evaluation, offering advantages not achievable with conventional single-point FSR-based systems.

[0018] These and other features and embodiments will be appreciated from the following description, the drawings and the claims.PCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCTBRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying figures, in which like reference numerals refer to identical or functionally similar elements throughout the separate views and which are incorporated in and form a part of the specification, further illustrate the present invention and, together with the detailed description of the invention, serve to explain the principles of the present invention.

[0020] FIG. 1 illustrates a front view of a CSB-SS device, which can be implemented in accordance with an embodiment;

[0021] FIG. 2 illustrates a back view of the CSB-SS device shown in FIG. 1 , in accordance with an embodiment;

[0022] FIG. 3 illustrates a schematic diagram depicting the structure of a monolithic 3DSI-FSR, in accordance with an embodiment;

[0023] FIG. 4 illustrates a front view of a 3D-FSR device, which can be implemented in accordance with an embodiment;

[0024] FIG. 5 illustrates a back view of the 3D-FSR device shown in FIG. 4, in accordance with an embodiment;

[0025] FIG. 6 illustrates a system and components of a 3D-FSR device, in accordance with an embodiment; and

[0026] FIG. 7 illustrates a flow diagram of a method for detecting bowing-related biomechanical characteristics and providing feedback to a classical string instrument player, in accordance with an embodiment.PCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCTDETAILED DESCRIPTION

[0027] The particular values and configurations discussed in these non-limiting examples can be varied and are cited merely to illustrate one or more embodiments and are not intended to limit the scope thereof.

[0028] Subject matter will now be described more fully hereinafter with reference to the accompanying drawings, which form a part hereof, and which show, by way of illustration, specific example embodiments. Subject matter may, however, be embodied in a variety of different forms and, therefore, covered or claimed subject matter is intended to be construed as not being limited to any example embodiments set forth herein; example embodiments are provided merely to be illustrative. Likewise, a reasonably broad scope for claimed or covered subject matter is intended. Among other things, for example, subject matter may be embodied as methods, devices, components, or systems. Accordingly, embodiments may, for example, take the form of hardware, software, firmware, or any combination thereof (other than software per se). The following detailed description is, therefore, not intended to be interpreted in a limiting sense.

[0029] Throughout the specification and claims, terms may have nuanced meanings suggested or implied in context beyond an explicitly stated meaning. Likewise, phrases such as “in one embodiment” or “in an example embodiment” and variations thereof as utilized herein do not necessarily refer to the same embodiment and the phrase “in another embodiment” or “in another example embodiment” and variations thereof as utilized herein may or may not necessarily refer to a different embodiment. It is intended, for example, that claimed subject matter include combinations of example embodiments in whole or in part.

[0030] In general, terminology may be understood, at least in part, from usage in context. For example, terms such as “and,” “or,” or “and / or” as used herein may include a variety of meanings that may depend, at least in part, upon the context in which such terms are used. Typically, “or” if used to associate a list, such as A, B, orPCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCTC, is intended to mean A, B, and C, here used in the inclusive sense, as well as A, B, or C, here used in the exclusive sense. In addition, the term “one or more” as used herein, depending at least in part upon context, may be used to describe any feature, structure, or characteristic in a singular sense or may be used to describe combinations of features, structures, or characteristics in a plural sense. Similarly, terms such as “a,” “an,” or “the”, again, may be understood to convey a singular usage or to convey a plural usage, depending at least in part upon context. In addition, the term “based on” may be understood as not necessarily intended to convey an exclusive set of factors and may, instead, allow for existence of additional factors not necessarily expressly described, again, depending at least in part on context. Furthermore, the term “at least one” as utilized herein can refer to “one or more”. For example, “at least one widget” may refer to “one or more widgets.”

[0031] Embodiments are related to a new hardware device and its variations with accompanying software that can be used to collect, analyze and present data about the actions of a person applying various forces to a classical stringed instrument (e.g., violin, viola, cello, bass, etc....) with a bow. The biomechanics of the bowing stroke of a player has a substantial effect on tone production, dexterity and potential injury to the player (fatigue, acute injury, repetitive motion injury, etc....). The embodiments can be used to characterize best practices of playing mechanics and style. This data can then be compared to user data both in real-time and for post-analysis to determine areas of improvement and player tendency. Mass user data may also be compiled and statistically analyzed to determine trends and identify patterns in player reported issues and user data.

[0032] Several variants of a classical string instrument bow sensing system (CSB- SS) device are presented herein with respect to varying embodiments. Each variant can be applicable to any classical string instrument and are intended to address various levels of player and types of playing concerns. Depending on the instrument a CSB-SS device is intended for, the body geometry varies slightly to match the structure and size of the bow for each instrument. However, the general structure and capability is the same within each variant type. These variants are described below.

[0033] A first variant can involve a CSB-SS Full Removable (CSB-SS-FR) device.PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCTSuch a device is full featured and user removeable and a user replaceable variant of the CSB-SS device. Sensing features can include, for example, attitude (orientation), linear and rotational acceleration, and touch point force application sensing. User feedback features can include haptic feedback through vibration, on-device visual feedback through onboard LED array or LCD screen, and data feedback through Bluetooth Low Energy and software visualization, analysis and storage.

[0034] A second variant can involve CSB-SS Full Built-In (CSB-SS-FB), which is a full featured and non-user-removable and non-user-replaceable variant of the CSB- SS device. Sensing features can include attitude (orientation), linear and rotational acceleration, touch point force application sensing, and string contact point along the bow. User feedback features can include haptic feedback though vibration, on-device visual feedback through onboard LED array or LCD screen, and data feedback through Bluetooth Low Energy and software visualization, analysis and storage.

[0035] A third variant can involve CSB-SS Simplified Built-In (CSB-SS-SB), which is a less featured, user-removable and user-replaceable variant of the CSB-SS device. Sensing features can include touch point force application sensing, and string contact point along the bow. User feedback features can include haptic feedback though vibration, and on-device visual feedback through onboard LED array or LCD screen.

[0036] A fourth variant can involve CSB-SS Body Only Removeable (CSB-SS-BR), which is a featureless and user-removable and user-replaceable variant of the CSB- SS device. This variant does not have to include sensing features and user feedback features.

[0037] A CBS-SS device can be constructed with several features including a target device body. For example, a user removeable CSB-SS device can include two main parts: the three dimensional (3D) printed device body and the electronics module. The CSB-SS device body can comprise a 3D printed semi-rigid plastic (PLA, ABS, PETG, PA, PET, ASA) or elastic polymer (TPU, TPE) and can be designed to conform to the shape and size of the instrument’s bow that it is intended for. The CBS-SS device can be constructed to be easily applied to, removed from, and / or integrated into the bow with its conforming shape and semi-rigidity allowing it to act as a compliant clampingPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT mechanism. The removable fastening mechanism can include any releasable securing technology such as hook-and-loop straps, elastic bands, compression sleeves, snap-fit elements, spring-loaded clips, adhesive pads, or combinations thereof. These mechanisms allow the CSB-SS-FR and CSB-SS-SB variants to be repeatedly installed and removed without damaging either the bow or device body.

[0038] In certain embodiments, the conductive traces, spacer layers, and resistive components of the 3DSI-FSR may be printed at varying depths within the device body. For example, traces may be deposited at the exterior surface of the device body, partially recessed into a shallow printed channel, or fully embedded beneath one or more subsequently printed dielectric layers. This approach enables the sensor to conform to complex bow geometries while allowing optimization of durability, sensitivity, and manufacturability. The term “printed into or onto” therefore encompasses surface deposition, in-body embedding, and hybrid multi-layer trace construction.

[0039] The device body can house up to five force sensors that can be located at the user touch points. The sensors can be implemented as three dimensional structurally integrated force sensitive resistors (3DSI-FSR) sensors and thus can be directly integrated into the device body. The 3DSI-FSR sensors can be printed into or onto the device body at the time of manufacture.

[0040] Referring to FIG. 1 , illustrated is a front view of a CSB-SS device 100, which can be implemented in accordance with an embodiment. Illustrated is the frame 110 of a bow having three locations that can incorporate three dimensional structurally integrated force sensitive resistors thereon / therein wherefrom pressure measurements can be obtained. The three locations are a pinky finger sense area 120, a thumb sense area 130, and an index finger sense area 140. Referring to FIG. 2 illustrated is a back view of the CSB-SS device 100 shown in FIG. 1 , in accordance with an embodiment. In this view, illustrated are two additional areas whereon / wherein three dimensional structurally integrated force sensitive resistors can be incorporated to produce measurements. These additional areas are a middle finger sense area 140 and a ring finger sense area 150.PCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCT

[0041] Also illustrated in FIG. 2 is a portion of index finger sense area 140 from FIG. 1 . The user of a bow can make contact with any of these sense areas to produce pressure on the bow and produce sensing (and performance) results. The sensing areas can be comprised of 3DSI-FSR sensors which are printed onto or into the device body (of the bow) itself. A printable piezoresistive filament suitable for use as a resistive layer can be utilized in the 3DSI-FSR sensors.

[0042] A piezoresistive sheet (i.e., Velostat) can also be used as the sensing medium. The printable piezoresistive material may include a thermoplastic or thermoplastic-elastomer base resin mixed with conductive additives such as carbon powder, graphene, metallic micro-particles, or carbon nanotubes. Material formulations may be tuned to achieve desired resistivity levels, pressure-sensitivity curves, and mechanical flexibility. When printed directly into the device body, this material forms a monolithic resistive layer capable of providing consistent forcesensing performance without the need for a separate Velostat sheet.

[0043] A diagram of a general structure of a monolithic Three-Dimensional Structurally Integrated Force Sensitive Resistor (3DSI-FSR) 300 is shown in FIG. 3, in accordance with an embodiment. FIG. 3 illustrates in a perspective view a 3DSI-FSR 300 that can solve issues associated with conventional FSRs. Conductive circuit traces 311 / 312 of the FSR circuits can be 3D printed directly onto, and / or otherwise integrated into, a surface of a sensor-bearing device body 305 (i.e., a bow for a string instrument), which is the structure that is the target for obtaining pressure measurements, rather than being produced as a separate entity and then applied to a surface of the sensor-bearing device body 305 (e.g., neck of a musical instrument, bow used to play a violine).

[0044] By application onto / into the sensor-bearing device body 305 as the target of measurement, a structurally integrated force Sensitive resistor (or “3DSI-FSR”) 300 can be achieved. To achieve this, a multi-material 3D printing process can be utilized. An electrically conductive material 310 can be used to print the circuit traces 311 / 312, and non-conductive material 315 can be used to sperate the conductive material 310, thereby forming traces 311 / 312. A spacer layer 320 can then be printed over areas of the non-conductive layer 315 outside and between traces 311 / 312 defined by the non-PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT conductive layer 315 to isolate the traces 311 / 312 from contact with a resistive layer 325 when pressure is not applied but allows contact between the traces 311 / 312 when pressure is applied onto the resistive layer 325.

[0045] Islands 321 can also be printed in-between traces 311 / 312 to facilitate isolation from the resistive layer 325. An optional top substrate 330 can be printed over the resistive layer 325 to insulate and protective the resistive layer 325 and underlying elements (i.e., conductive material 310, traces 311 / 312, etc.), which comprise elements of the sensing device itself that can be applied to the structure 305.

[0046] It is an advantage that, unlike traditional FSRs, the 3DSI-FSR disclosed herein does not have a separate bottom substrate and instead it is the target of measurement itself (i.e., a bow) that can serve as the supporting structure for the circuit traces 311 / 312, which can be printed directly onto / integrated into the sensorbearing device body 305. This approach eliminates the added thickness of a separate substrate layer, allowing the sensor to conform to complex geometries with minimal bulk. The sensor-bearing device body 305 (the target) can be printed out of any number of dielectric materials such as PLA, PETG, ABS, ASA, PA, TPU, TPE, PET, etc.

[0047] Furthermore, the integrally printed 3DSI-FSR sensor traces 311 / 312 can be printed as a matrix onto / into the structure of the sensor body 305. Depending on the specific geometry, thickness, material, and use case of the sensor-bearing device the circuit traces may be printed at the surface level or below. The 3DSI-FSR sensor traces 311 / 312 can be printed out of conductive variants of the same materials as the resistive Iayer325, but do not exclusively have to be printed out of a similar material. These conductive material variants can typically be impregnated with suspended metallic, carbon black, or carbon nanotube particles.

[0048] The spacer layer 320 can be printed using a dielectric, elastic filament such as TPU or TPE and serves to separate the traces and resistive layer until force is applied to the sensor. Regarding the resistive layer 325, current prototypes of the 3DSI-FSR's resistive layer use a conventional sheet of piezoresistive material for the resistive layer. However, the disclosed embodiments can involve the development ofPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT an FDM-printable piezoresistive material that can allow for the resistive layer 325 to be printed directly within the device structure. This advancement can enable a fully monolithic design, allowing for zero added thickness -- an important advantage for applications requiring a minimal form factor.

[0049] The circuit traces 311 / 312 for each column and row of the 3DSI-FSR lie in the touch point sensing areas indicated above and can be connected through the body of the device by a common termination area where an electrical connection between the device body and the electronics module will be emplaced. The body of the device is shown to be semi-transparent for the purpose of illustrating components of FIG. 4 and FIG. 5.

[0050] Referring to FIG. 4, illustrated is a front view of a 3DSI-FSR device 400, which can be implemented in accordance with an embodiment. Illustrated is a bow body 410 whereon / wherein various sense areas can be incorporated on / in the bow body 410. A pinky finger sense area 420 can included 3dSI-FSR traces. A ring finger sense integration area 430 is also shown including 3dSI-FSR traces. A middle finger sense area 440, thumb sense area 450 and includes finger sense area 460 also show 3dSI-FSR trace elements incorporate therein. A common trace termination area 470 is shown wherein electrical connection to the sensing areas from a microcontroller (not shown, see FIG. 6) can be achieved. Referring to FIG. 5, illustrated is a back view of the 3DSI-FSR device 400 shown in FIG. 4 is illustrated with sensing component locations are once again revealed but from a backside perspective.

[0051] For permanently integrated embodiments, the device body may be bonded to the bow stick using structural epoxy, UV-curable adhesive, resin infusion, thermal bonding, or mechanical interlock features printed into the device body. In certain designs, the device body may be co-manufactured with the bow s tick, such as through over molding, co-extrusion, partial embedding of printed components into the bow material, or manufacturing the bow stick itself from a composite structure incorporating the 3DSI-FSR matrix.

[0052] The common trace termination area 470 may include one or more printed contact pads, embedded conductive vias, flexible flat cables, or a detachable micro-PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT connector. Conductive pathways routed from each 3DSI-FSR sensing region converge at this termination area, permitting simplified electrical coupling to the electronics module through soldered joints, crimped connectors, or spring-loaded pogo-pin contacts.

[0053] In an embodiment, a CSB-SS an electronics module can be implemented. That is, the main component of the electronics module is a microcontroller / microprocessor, which can be used to regulate power, read and write voltages, provide onboard data processing, and manage data telemetry.

[0054] Referring to FIG. 6, a system diagram for electronics modules of a CSB-SS 600 is illustrated wherein a microcontroller 610 can manage several submodules of a CSB-SS including a BLE (Bluetooth) module 620, a 9-degree freedom (DoF) inertial measurement unit (IMU) 625, a vibration module 630, and an on-device visual feedback module 635. The BLE module 620 can be used to communicate with and telemeter data to the device hosting the system software (phone, tablet, PC). The 9 degree of freedom (DoF) inertial measurement unit (IMU) 625 can be used to determine the physical orientation and motion of the bow. The IMU 625 can also contain a group of submodules including an accelerometer, a gyroscope, and a magnetometer.

[0055] An accelerometer can be used to measure linear acceleration. A gyroscope can be used to measure rotational acceleration. A magnetometer can be used to measure directional magnetic field strength. The vibration module 630 can be used provide haptic feedback to the user via vibrational pulses. The on-device visual feedback module 635 can be used to provide visual feedback to the user. The on- device visual feedback module may also include an LED array or LCD display and can be used to provide real time data and or device status information.

[0056] The electronics modules can be miniaturized in some embodiments, along with the housing and the location of the module is TBD. Current prototyping efforts have the electronics modules within a 3D printed housing mounted to the left side of and below the bow frog. With miniaturization, the casement may be smaller and simplified as the electronics held therein will be substantially smaller and simplerPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT geometrically.

[0057] Regarding construction of the CSB-SS device, the non-user-removable and non-user-replaceable CSB-SS device can include two main parts: the three dimensional (3D) printed device body and the electronics module. The CSB-SS-FB device body can include a 3D printed semi-rigid plastic (PLA, ABS, PETG, PA, PET, ASA) or elastic polymer (TPU, TPE) and has been designed to conform to the shape and size of the instrument’s bow that it is intended for. Unlike the CSB-SS-FR device body, the CSB-SS-FB can be designed to be permanently affixed to the bow and this body design may be changed to accommodate this. However, the user-facing geometry and integrated sensor and circuit design will remain identical to the CSB- SS-FR.

[0058] The CSB-SS-FB Electronics module is similar to the CSB-SS-FR electronics module with one addition. One or more Hall effect sensors can be placed along the shaft of the bow and facilitate determination of the contact location with the strings along the length of the bow. For the electronics enclosure and mounting system two options can be considered. A similar solution to the CSB-SS-FR electronics enclosure but permanently affixed. In some embodiments, custom bow frogs can be produced, which are hollow and can allow us to enclose the electronics module within the bow frog itself. This can allow for the best balance and least intrusive user experience possible.

[0059] The Hall-effect subsystem can operate with one or more magnetic field sources affixed to the bow hair, frog, or a reference area of the bow stick. The Halleffect sensors may detect relative changes in magnetic field strength as the bow position shifts over the string array. A processing algorithm may correlate detected field variations with the known spatial arrangement of the instrument’s strings to determine instantaneous bow-to-string contact location.

[0060] The CSB-SS-SB device is a user removeable CSB-SS device comprising two main parts: a three dimensional (3D) printed device body and an electronics module. The CSB-SS-SB device body is identical to the body of the CSB-SS-FB device. The CSB-SS-SB Electronics module can be simplified from the CSB-SS-FR.PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCTThe main component of the electronics module is a microcontroller / microprocessor used to regulate power, read and write voltages, provide onboard data processing, and manage data telemetry. The microcontroller / microcontroller can manage several submodules including, for example a vibration module and an on-device visual feedback module.

[0061] The vibration module can be used to provide haptic feedback to the user via vibrational pulses. The on-device visual feedback module can be used to provide visual feedback to the user. The on-device visual feedback module may include an LED array or LCD display and can be used to provide real time data and or device status information. Furthermore, Hall effect sensors can be placed along the shaft of the bow and facilitate determination of the contact location with the strings along the length of the bow. Similar miniaturization and enclosure efforts will be taken as to the CSB-SS-FB electronics. However, efforts should be made easier to do the simplified nature of the CSB-SS-SB electronics vs the CSB-SS-FR and CSB-SS-FB electronics.

[0062] The user removeable CSB-SS device can include main parts: the three dimensional (3D) printed device body and the electronics module. The CSB-SS-SB device body can be geometrically identical to the body of the CSB-SS-FR device. The CSB-SS-BR device may have no electrical features. There is also no CSB-SS-SB electronics module in this embodiment.

[0063] Referring to FIG. 7, illustrated is an example method 700 for detecting bowing biomechanics and providing real-time or post-session feedback to a user, in accordance with an embodiment. Although specific steps and operations are shown in a particular order for clarity, the steps may be performed in different orders, in parallel, or omitted entirely depending on the implementation. As indicated at block 710, a step or operation can be implemented in which the system initializes one or more sensing components including the plurality of 3DSI-FSRs, the inertial measurement unit (IMU), and optional Hall-effect sensors. Initialization may include steps or operations involving calibration of sensor offsets, sampling-rate configuration, wireless-module activation, and loading of firmware parameters or lookup tables.

[0064] Next, as indicated at block 720, a step or operation can be implemented inPCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCT which the system can detect force distributions applied at one or more user touch points of the bow. The 3DSI-FSRs generate real-time resistance changes corresponding to pressure profiles exerted by the thumb, index finger, middle finger, ring finger, or pinky finger. These analog signals may be conditioned, digitized, and buffered by the microcontroller. Thereafter, as shown at block 730, a step or operation can be implemented in which the system acquires motion data from the IMU including linear acceleration, rotational acceleration, and orientation of the bow. In certain embodiments, magnetic-field measurements from the magnetometer are used to improve orientation stability. Optional Hall-effect sensors may provide a bow-to-string contact position at this stage.

[0065] Thereafter, as shown at block 740, a step or operation can be implemented in which the system performs onboard processing of sensor signals. Processing may include noise filtering, drift compensation, normalization, and extraction of higher- order parameters such as force balance, temporal patterns, stroke type, motion smoothness, and potential risk indicators for poor technique or strain. Next, as illustrated at block 750, the processed data can be transmitted via wireless communication (e.g., Bluetooth Low Energy) to an external device such as a smartphone, tablet, or computer. The external device may execute software configured to display real-time graphs, biomechanical overlays, comparative analysis, or long-term practice metrics.

[0066] Then, as shown at block 760, a step or operation can be implemented in which the system optionally generates real-time feedback to the user. The electronics module may actuate a vibration motor to deliver haptic cues, activate LEDs or an LCD display for visual alerts, or issue audio signals through a connected device. Feedback may correspond to excessive downward force, improper finger balance, bow tilt, stringcontact anomalies, or deviations from a target practice pattern. Next, as depicted at block 770, the system may store session data locally or remotely for later retrieval and post-session analysis. Stored data may include raw sensor streams, processed metrics, or summary statistics used for student-teacher review, long-term technique tracking, or injury-prevention analytics. The operations of method 700 can then end, although additional operations such as re-calibration, practice-mode switching, or firmware updates may also be implemented in additional steps or operations as partPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT of method 700. The described process enables a fully integrated, high-resolution biomechanical analysis workflow for classical string instrument players.

[0067] The operations shown in FIG. 7 may be implemented entirely on the electronics module, partly on the electronics module and partly on an external device, or entirely on an external device receiving raw or semi-processed sensor data. The operations illustrated in FIG. 7 represent one possible arrangement of functions already described herein, and do not limit the order, inclusion, or combination of steps. The flow diagram is provided merely to illustrate functionality already disclosed in this specification.

[0068] In certain embodiments, the firmware executed on the microcontroller may include state machines, digital filters, lookup tables, and parameterized models for interpreting force-sensing and motion-sensing data. The methods described herein may be implemented as instructions stored in non-transitory memory and executed by the microcontroller or by a processor of an external device. The term “non-transitory memory” includes RAM, flash memory, EEPROM, or similar storage media. In a minimal configuration, the method may utilize only the 3DSI-FSR sensors to detect user-applied forces without requiring inertial measurement or string-contact detection. In such embodiments, the system may perform simplified feedback operations based solely on detected pressure patterns, enabling a lightweight, low-cost version of the CSB-SS.

[0069] The system can support multiple operational modes including practice mode, real-time feedback mode, performance recording mode, or calibration mode. Each mode may adjust sampling rates, filtering parameters, thresholds for feedback triggering, and data-logging criteria. Biomechanical interpretation may include quantifying finger-force balance, timing accuracy, bow-tilt uniformity, stroke initiation behavior, bow velocity smoothness, force impulses, fatigue patterns, or repetitive- strain risk factors. These interpretations may be generated automatically based on sensor data or presented to users as graphical or statistical summaries.

[0070] Based on the foregoing, it can be appreciated that the embodiments offer several novel features. For example, the embodiments can include multi-point forcePCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCT sensing of use input to classical stringed instrument bows. Conventional approaches have included only single point force application sensing. The embodiments can also include 3DSI-FSR sensors including, for example, embedded force-sensitive resistors integrated into the active 3D printed CSB-SS devices. The embodiments also can include user feedback options involving, for example, haptic feedback, on-device visual feedback, real time feedback through BLE telemetered data to software to provide real-time insights into the bowing technique. Embodiments can also offer software integration for analysis. That is, the system can provide database storage and post analysis to track progress, highlight issues, and compare performance to best practices. Additionally, string contact position determination can be implemented via a hall effect sensor.

[0071] In operational use, the sensing module continuously samples force data from the 3DSI-FSRs and motion data from the IMU. The microcontroller may execute firmware configured to filter noise, compensate for drift, and compute force distributions, timing patterns, and bow orientation parameters. Processed or raw data may be transmitted wirelessly to an external device such as a mobile phone, tablet, or computer, where software visualization tools can present real-time biomechanical feedback, generate practice metrics, or store historical performance data for postsession analysis.

[0072] The CSB-SS-FR and CSB-SS-FB and to a more limited extent the CSB-SS- SB devices can address the lack of effective, objective feedback for classical string instrument players. Traditionally, it is challenging for musicians to fully understand their mistakes because they often lack real-time insights into their own actions. This is why private instruction has long been the gold standard in music education — offering the experience and perception of a skilled instructor. However, private lessons come with drawbacks: they are expensive, have limited availability, and rely on visual and auditory observations, which may overlook subtle nuances in technique. These limitations can hinder progress, increase the risk of injury due to poor technique, and make it difficult to track improvements.

[0073] This issue is not unique to music. Athletes face similar challenges when refining dexterous skills. In sports, human observation-based coaching has evolvedPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT significantly with the integration of sports science and sensor technology, enabling precise feedback, data tracking, and improved performance analysis. The embodiments including the CSB-SS and its active variation, can apply these principles to classical string playing, offering several advantages. Precise feedback can identify mechanical and timing issues in a player's technique (biomechanics). Comparative analysis can allow comparison between players to highlight differences in technique. Correlation insights can connect playing techniques with musical quality or injury risk. Progress tracking can monitor player progression and practice volume over time. IS system as disclosed can provides quantitative data that has not previously been available for classical string music technique. By providing precise sensor data, features of the disclosed system empower players to learn more effectively, independently, and with less reliance on subjective perception. Additionally, it can equip teachers with detailed insights into their students’ techniques, enhancing the quality of feedback they can provide.

[0074] The CBS-SS-BR in testing has shown to provide some benefit to the player even as a device with no integrated electronics as it provides improved tactile feedback of thumb positions which is particularly critical to the bow technique. Therefore, we may pursue it as a standalone offering.

[0075] The embodiments can be implemented in several different applications, such as, for example private instruction is enhanced with in-person and remote lessons by providing objective performance data. Institutional training supports collegiate and conservatory programs with data-driven insights for student musicians. Classroom learning assists in public school orchestra programs to improve student learning outcomes. Injury analysis identifies root causes of playing-related injuries and suggests mitigation strategies. In real-time biofeedback for preventing injury, the system can identify force imbalances that could lead to repetitive strain injuries. This feature can be especially appealing to professionals.

[0076] Potential Stakeholders and Interested Organizations can involve, for example educational institutions such as colleges, conservatories, and public schools can be enhanced with classical string programs. Private instructors such a teacherPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT looking to enhance the quality of their lessons can benefit from the features disclosed herein. Musicians, both amateur and professional, interested in improving their skills can benefit from aspects of the embodiments.

[0077] Future Applications can also involve expansion into other musical genres and instruments beyond classical strings. For example, applications may involve integration into sports and physical therapy for enhancing motor skill training through precise feedback.

[0078] Based on the foregoing, it can be appreciated that varying embodiments are disclosed. For example, in an embodiment, a sensing system for classical string instrument bows, can include: a plurality of force-sensitive resistors structurally attached to or integrated into a device body in a shape and size of a bow for a classical string instrument, the device body configured from a semi-rigid or elastic polymer material, the resistors comprising three-dimensional force-sensitive resistors (3DSI- FSRs) configured as a part of the device body; and a sensing module configured to detect forces applied at user touch points on the bow.

[0079] In an embodiment, the sensing module can be further configured to measure orientation of the bow and linear and rotational acceleration of the bow.

[0080] An embodiment can further include a user feedback module including: a haptic feedback mechanism, a visual feedback system including at least one of an LED array or an LCD screen, and a wireless communication interface for transmitting sensor data to an external device.

[0081] An embodiment can further include a removable fastening mechanism for securing the plurality of force-sensitive resistors to the bow.

[0082] In an embodiment, a sensing system for a classical string instrument bow, can include: a device body configured to conform to a shape and size of a bow for a classical string instrument, the device body comprising a semi-rigid or elastic polymer material; a plurality of force-sensitive resistors structurally attached to or integrated into the device body, the plurality of force-sensitive resistors comprising three- dimensional structurally integrated force-sensitive resistors (3DSI-FSRs) printed intoPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT or onto the device body at user touch point locations; and a sensing module configured to detect forces applied to the user touch point locations.

[0083] In an embodiment, the sensing module can be further configured to measure at least one of: (i) orientation of the bow, (ii) linear acceleration of the bow, or (iii) rotational acceleration of the bow.

[0084] An embodiment can further include a user feedback module including: a haptic feedback mechanism, a visual feedback system comprising at least one of an LED array or an LCD display, and a wireless communication interface configured to transmit sensor data to an external device.

[0085] An embodiment can further include a removable fastening mechanism configured to secure the device body to the bow.

[0086] In an embodiment, the 3DSI-FSRs can include conductive circuit traces printed directly onto or within the device body using a conductive polymeric material containing metallic particles, carbon black, or carbon nanotubes.

[0087] An embodiment can further include a spacer layer formed from a dielectric elastic material separates the conductive circuit traces from a resistive layer until an external force is applied to the device body.

[0088] In an embodiment, the resistive layer can include a piezoresistive sheet or a directly printed piezoresistive polymer.

[0089] In an embodiment, the user touch point locations can include one or more of, for example, a thumb contact region, an index finger contact region, a middle finger contact region, a ring finger contact region, or a pinky finger contact region.

[0090] An embodiment can further include a common termination area integrated into the device body and electrically coupled to the plurality of 3DSI-FSRs for connection to the sensing module.

[0091] In an embodiment, the device body can include a multi-material 3D-printed structure including one or more of: PLA, ABS, PETG, PA, PET, ASA, TPU, or TPE.PCT PATENT APPLICATIONAttorney Docket No. TACTUS-1002PCT

[0092] In an embodiment, a classical string instrument bow can include a bow stick; and a sensing assembly permanently affixed to the bow stick, the sensing assembly comprising a device body conforming to the bow stick, a plurality of integrated 3DSI- FSRs printed into or onto the device body, and an electronics module configured to detect forces applied at multiple user contact regions of the bow.

[0093] In an embodiment, the electronics module can further include a Hall-effect sensing subsystem configured to determine a string-contact location along the length of the bow.

[0094] In an embodiment, the electronics module can be enclosed within a customized bow frog.

[0095] In an embodiment, the device body can be non-removable and permanently bonded to the bow stick.

[0096] In an embodiment, the electronics module can include a microcontroller configured to process sensor signals and manage data transmission through a Bluetooth Low Energy interface.

[0097] In an embodiment, a method of detecting bowing-related biomechanical characteristics of a classical string instrument player, can involve: providing a device body conforming to a bow, the device body comprising a plurality of integrated 3DSI- FSRs at user touch point locations; detecting, via the plurality of 3DSI-FSRs, force distributions applied by at least one finger of the player; and transmitting sensor data from the bow to an external device for real-time feedback or post-session analysis.

[0098] An embodiment of the method can further involve measuring at least one of: bow orientation, linear acceleration, or rotational acceleration using an inertial measurement unit integrated into the bow.

[0099] An embodiment of the method can further involve providing real-time haptic feedback to the player based on the detected force distributions.

[0100] An embodiment of the method can further involve visually displaying bowing-PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT related parameters on an LED array or LCD display located on the bow.

[0101] An embodiment of the method can further involve identifying a contact point of the bow along a set of strings using at least one Hall-effect sensor mounted on the bow.

[0102] It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. It will also be appreciated that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

Claims

PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCTCLAIMSWhat is claimed is:1 . A sensing system for classical string instrument bows, comprising: a plurality of force-sensitive resistors structurally attached to or integrated into a device body in a shape and size of a bow for a classical string instrument, the device body configured from a semi-rigid or elastic polymer material, the resistors comprising three-dimensional force-sensitive resistors (3DSI-FSRs) configured as a part of the device body; and a sensing module configured to detect forces applied at user touch points on the bow.

2. The sensing system of claim 1 , wherein the sensing module is further configured to measure orientation of the bow and linear and rotational acceleration of the bow.

3. The sensing system of claim 1 , further comprising a user feedback module including: a haptic feedback mechanism, a visual feedback system including at least one of an LED array or an LCD screen, and a wireless communication interface for transmitting sensor data to an external device.

4. The sensing system of claim 1 , further comprising a removable fastening mechanism for securing the plurality of force-sensitive resistors to the bow.1 . A sensing system for a classical string instrument bow, comprising: a device body configured to conform to a shape and size of a bow for a classical string instrument, the device body comprising a semi-rigid or elastic polymer material; a plurality of force-sensitive resistors structurally attached to or integrated into the device body, the plurality of force-sensitive resistors comprising three-dimensionalPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT structurally integrated force-sensitive resistors (3DSI-FSRs) printed into or onto the device body at user touch point locations; and a sensing module configured to detect forces applied to the user touch point locations.

2. The sensing system of claim 1 , wherein the sensing module is further configured to measure at least one of: (i) orientation of the bow, (ii) linear acceleration of the bow, or (iii) rotational acceleration of the bow.

3. The sensing system of claim 1 , further comprising a user feedback module including: a haptic feedback mechanism, a visual feedback system comprising at least one of an LED array or an LCD display, and a wireless communication interface configured to transmit sensor data to an external device.

4. The sensing system of claim 1 , further comprising a removable fastening mechanism configured to secure the device body to the bow.

5. The sensing system of claim 1 , wherein the 3DSI-FSRs comprise conductive circuit traces printed directly onto or within the device body using a conductive polymeric material containing metallic particles, carbon black, or carbon nanotubes.

6. The sensing system of claim 5, wherein a spacer layer formed from a dielectric elastic material separates the conductive circuit traces from a resistive layer until an external force is applied to the device body.

7. The sensing system of claim 6, wherein the resistive layer comprises a piezoresistive sheet or a directly printed piezoresistive polymer.

8. The sensing system of claim 1 , wherein the user touch point locations include at least one of: a thumb contact region, an index finger contact region, a middle finger contact region, a ring finger contact region, or a pinky finger contact region.

9. The sensing system of claim 1 , further comprising a common termination areaPCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT integrated into the device body and electrically coupled to the plurality of 3DSI-FSRs for connection to the sensing module.

10. The sensing system of claim 1 , wherein the device body comprises a multimaterial 3D-printed structure including at least one of: PLA, ABS, PETG, PA, PET, ASA, TPU, or TPE.11 . A classical string instrument bow comprising: a bow stick; and a sensing assembly permanently affixed to the bow stick, the sensing assembly comprising a device body conforming to the bow stick, a plurality of integrated 3DSI-FSRs printed into or onto the device body, and an electronics module configured to detect forces applied at multiple user contact regions of the bow.

12. The bow of claim 11 , wherein the electronics module further comprises a Halleffect sensing subsystem configured to determine a string-contact location along the length of the bow.

13. The bow of claim 11 , wherein the electronics module is enclosed within a customized bow frog.

14. The bow of claim 11 , wherein the device body is non-removable and permanently bonded to the bow stick.

15. The bow of claim 11 , wherein the electronics module includes a microcontroller configured to process sensor signals and manage data transmission through a Bluetooth Low Energy interface.

16. A method of detecting bowing-related biomechanical characteristics of a classical string instrument player, comprising: providing a device body conforming to a bow, the device body comprising a plurality of integrated 3DSI-FSRs at user touch point locations; detecting, via the plurality of 3DSI-FSRs, force distributions applied by at least one finger of the player; and transmitting sensor data from the bow to an external device for real-time feedback or post-session analysis.PCT PATENT APPLICATION Attorney Docket No. TACTUS-1002PCT17. The method of claim 16, further comprising measuring at least one of: bow orientation, linear acceleration, or rotational acceleration using an inertial measurement unit integrated into the bow.

18. The method of claim 16, further comprising providing real-time haptic feedback to the player based on the detected force distributions.

19. The method of claim 16, further comprising visually displaying bowing-related parameters on an LED array or LCD display located on the bow.

20. The method of claim 16, further comprising identifying a contact point of the bow along a set of strings using at least one Hall-effect sensor mounted on the bow.

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