{"id":{"repo_id":"uic","oai_identifier":"oai:figshare.com:article/32995286"},"canonical_url":"https://search.dev.ndltd.org/etd/uic/oai:figshare.com:article/32995286","repository":{"repo_id":"uic","name":"University of Illinois - Chicago","base_url":"https://api.figshare.com/v2/oai"},"display":{"title":"Development of an Industrially Deployable Personalized Ankle–Foot Orthosis System","abstract":"This dissertation presents the development and validation of a personalized, field-deployable ankle–foot orthosis (AFO) system designed to assist industrial tasks like squatting. Industrial workers frequently suffer from lower limb fatigue and musculoskeletal injuries due to repetitive lifting and squatting. While robotic AFOs have shown potential to reduce this physical burden, most existing systems are limited to laboratory settings due to their reliance on tethered equipment and slow optimization methods based on metabolic cost. To address these limitations, this research integrates physiological personalization with a portable hardware platform to realize a truly field-ready assistive system. The research begins by establishing a practical method for physiological personalization (Chapters 2 and 3). Conventional Human-in-the-Loop (HIL) optimization uses metabolic cost, which is too slow for real-world applications. In Chapter 2, I investigated electromyography (EMG) as a rapid alternative proxy. Through squatting experiments, I identified that the activation of the Rectus Femoris (RF) muscle and specific muscle synergies are highly correlated with metabolic effort. Based on this finding, Chapter 3 details the implementation of an EMG-based HIL optimization. The results demonstrated that minimizing RF activation in real-time successfully reduced physical effort without inducing compensatory movements. This confirmed that physiological personalization is feasible without cumbersome respiratory measurement equipment. Following the validation of the control algorithm, Chapters 4 and 5 detail the resolution of the second gap which is the development of a portable emulator system. While tethered lab systems can render any torque profile, they are immobile. Conversely, existing portable exoskeletons function primarily as simulators with fixed or limited stiffness profiles. To overcome this, Chapter 4 focuses on the mechanical evolution of a 3D printed modular AFO to ensure structural robustness and personalization capabilities. Subsequently, Chapter 5 presents the development of a high bandwidth Portable Actuation System (PAS). I developed a compact control unit that integrates powerful brushless DC motors, a real time industrial controller (Beckhoff SBC), and a custom EtherCAT and CAN communication bridge. Evaluation results confirmed a high control bandwidth of over 10 Hz. Although initial structural limitations were identified at torques exceeding 40 Nm, collaborative failure analysis and further design evolution with fellow researcher A. Patel successfully expanded the torque capacity to 80 Nm in a subsequent iteration. This established the hardware as a robust Portable Emulator capable of rendering high fidelity and laboratory quality assistance profiles in the field. Finally, Chapter 6 integrates the optimized control strategy and the portable hardware to demonstrate field deployment. To make the system more practical for outdoor environments, I adopted Heart Rate Variability (specifically RMSSD) derived from a wearable ECG sensor as a global cost function, replacing the multiple EMG sensors which can be intrusive. I conducted a field validation in a real-world hallway environment, where the portable system autonomously optimized assistance parameters during walking and squatting tasks. The on-device HIL optimization successfully converged to subject-specific parameters, and the validation results showed a strong positive trend in reducing metabolic cost compared to unpowered and generic conditions. In conclusion, this dissertation bridges the gap between theoretical robotic control and practical field application. By identifying a fast physiological proxy (Aim I), building a robust portable system (Aim II), and validating it in a real-world environment with wearable sensors (Aim III), this work establishes a comprehensive framework for industrially deployable personalized wearable robots","abstract_html":"This dissertation presents the development and validation of a personalized, field-deployable ankle–foot orthosis (AFO) system designed to assist industrial tasks like squatting. Industrial workers frequently suffer from lower limb fatigue and musculoskeletal injuries due to repetitive lifting and squatting. While robotic AFOs have shown potential to reduce this physical burden, most existing systems are limited to laboratory settings due to their reliance on tethered equipment and slow optimization methods based on metabolic cost. To address these limitations, this research integrates physiological personalization with a portable hardware platform to realize a truly field-ready assistive system. The research begins by establishing a practical method for physiological personalization (Chapters 2 and 3). Conventional Human-in-the-Loop (HIL) optimization uses metabolic cost, which is too slow for real-world applications. In Chapter 2, I investigated electromyography (EMG) as a rapid alternative proxy. Through squatting experiments, I identified that the activation of the Rectus Femoris (RF) muscle and specific muscle synergies are highly correlated with metabolic effort. Based on this finding, Chapter 3 details the implementation of an EMG-based HIL optimization. The results demonstrated that minimizing RF activation in real-time successfully reduced physical effort without inducing compensatory movements. This confirmed that physiological personalization is feasible without cumbersome respiratory measurement equipment. Following the validation of the control algorithm, Chapters 4 and 5 detail the resolution of the second gap which is the development of a portable emulator system. While tethered lab systems can render any torque profile, they are immobile. Conversely, existing portable exoskeletons function primarily as simulators with fixed or limited stiffness profiles. To overcome this, Chapter 4 focuses on the mechanical evolution of a 3D printed modular AFO to ensure structural robustness and personalization capabilities. Subsequently, Chapter 5 presents the development of a high bandwidth Portable Actuation System (PAS). I developed a compact control unit that integrates powerful brushless DC motors, a real time industrial controller (Beckhoff SBC), and a custom EtherCAT and CAN communication bridge. Evaluation results confirmed a high control bandwidth of over 10 Hz. Although initial structural limitations were identified at torques exceeding 40 Nm, collaborative failure analysis and further design evolution with fellow researcher A. Patel successfully expanded the torque capacity to 80 Nm in a subsequent iteration. This established the hardware as a robust Portable Emulator capable of rendering high fidelity and laboratory quality assistance profiles in the field. Finally, Chapter 6 integrates the optimized control strategy and the portable hardware to demonstrate field deployment. To make the system more practical for outdoor environments, I adopted Heart Rate Variability (specifically RMSSD) derived from a wearable ECG sensor as a global cost function, replacing the multiple EMG sensors which can be intrusive. I conducted a field validation in a real-world hallway environment, where the portable system autonomously optimized assistance parameters during walking and squatting tasks. The on-device HIL optimization successfully converged to subject-specific parameters, and the validation results showed a strong positive trend in reducing metabolic cost compared to unpowered and generic conditions. In conclusion, this dissertation bridges the gap between theoretical robotic control and practical field application. By identifying a fast physiological proxy (Aim I), building a robust portable system (Aim II), and validating it in a real-world environment with wearable sensors (Aim III), this work establishes a comprehensive framework for industrially deployable personalized wearable robots","abstract_has_math":false,"creators":["Hyeongkeun Jeong (13105155)"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2026,"date_issued":"2026-05-01T00:00:00Z","date_published":"2026-05-01T00:00:00Z","updated_at":"2026-07-27T21:33:53Z","subjects":["Engineering, Robotics","Engineering, Mechanical"],"languages":[],"rights":["In Copyright","Open Access after 2028-05-01"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://doi.org/10.25417/uic.32995286.v1","outbound_label":"DOI","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Hyeongkeun Jeong (13105155)"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2026-05-01T00:00:00Z"]},{"key":"dc:relation","label":"Dc Relation","values":["https://figshare.com/articles/thesis/Development_of_an_Industrially_Deployable_Personalized_Ankle_Foot_Orthosis_System/32995286"]},{"key":"dc:type","label":"Dc Type","values":["Text","Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Engineering, Robotics","Engineering, Mechanical"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright","Open Access after 2028-05-01"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["10.25417/uic.32995286.v1"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["This dissertation presents the development and validation of a personalized, field-deployable ankle–foot orthosis (AFO) system designed to assist industrial tasks like squatting. Industrial workers frequently suffer from lower limb fatigue and musculoskeletal injuries due to repetitive lifting and squatting. While robotic AFOs have shown potential to reduce this physical burden, most existing systems are limited to laboratory settings due to their reliance on tethered equipment and slow optimization methods based on metabolic cost. To address these limitations, this research integrates physiological personalization with a portable hardware platform to realize a truly field-ready assistive system. The research begins by establishing a practical method for physiological personalization (Chapters 2 and 3). Conventional Human-in-the-Loop (HIL) optimization uses metabolic cost, which is too slow for real-world applications. In Chapter 2, I investigated electromyography (EMG) as a rapid alternative proxy. Through squatting experiments, I identified that the activation of the Rectus Femoris (RF) muscle and specific muscle synergies are highly correlated with metabolic effort. Based on this finding, Chapter 3 details the implementation of an EMG-based HIL optimization. The results demonstrated that minimizing RF activation in real-time successfully reduced physical effort without inducing compensatory movements. This confirmed that physiological personalization is feasible without cumbersome respiratory measurement equipment. Following the validation of the control algorithm, Chapters 4 and 5 detail the resolution of the second gap which is the development of a portable emulator system. While tethered lab systems can render any torque profile, they are immobile. Conversely, existing portable exoskeletons function primarily as simulators with fixed or limited stiffness profiles. To overcome this, Chapter 4 focuses on the mechanical evolution of a 3D printed modular AFO to ensure structural robustness and personalization capabilities. Subsequently, Chapter 5 presents the development of a high bandwidth Portable Actuation System (PAS). I developed a compact control unit that integrates powerful brushless DC motors, a real time industrial controller (Beckhoff SBC), and a custom EtherCAT and CAN communication bridge. Evaluation results confirmed a high control bandwidth of over 10 Hz. Although initial structural limitations were identified at torques exceeding 40 Nm, collaborative failure analysis and further design evolution with fellow researcher A. Patel successfully expanded the torque capacity to 80 Nm in a subsequent iteration. This established the hardware as a robust Portable Emulator capable of rendering high fidelity and laboratory quality assistance profiles in the field. Finally, Chapter 6 integrates the optimized control strategy and the portable hardware to demonstrate field deployment. To make the system more practical for outdoor environments, I adopted Heart Rate Variability (specifically RMSSD) derived from a wearable ECG sensor as a global cost function, replacing the multiple EMG sensors which can be intrusive. I conducted a field validation in a real-world hallway environment, where the portable system autonomously optimized assistance parameters during walking and squatting tasks. The on-device HIL optimization successfully converged to subject-specific parameters, and the validation results showed a strong positive trend in reducing metabolic cost compared to unpowered and generic conditions. In conclusion, this dissertation bridges the gap between theoretical robotic control and practical field application. By identifying a fast physiological proxy (Aim I), building a robust portable system (Aim II), and validating it in a real-world environment with wearable sensors (Aim III), this work establishes a comprehensive framework for industrially deployable personalized wearable robots"]},{"key":"dc:title","label":"Title","values":["Development of an Industrially Deployable Personalized Ankle–Foot Orthosis System"]}]}],"canonical_facts":{"dc:creator":["Hyeongkeun Jeong (13105155)"],"dc:date":["2026-05-01T00:00:00Z"],"dc:description":["This dissertation presents the development and validation of a personalized, field-deployable ankle–foot orthosis (AFO) system designed to assist industrial tasks like squatting. Industrial workers frequently suffer from lower limb fatigue and musculoskeletal injuries due to repetitive lifting and squatting. While robotic AFOs have shown potential to reduce this physical burden, most existing systems are limited to laboratory settings due to their reliance on tethered equipment and slow optimization methods based on metabolic cost. To address these limitations, this research integrates physiological personalization with a portable hardware platform to realize a truly field-ready assistive system. The research begins by establishing a practical method for physiological personalization (Chapters 2 and 3). Conventional Human-in-the-Loop (HIL) optimization uses metabolic cost, which is too slow for real-world applications. In Chapter 2, I investigated electromyography (EMG) as a rapid alternative proxy. Through squatting experiments, I identified that the activation of the Rectus Femoris (RF) muscle and specific muscle synergies are highly correlated with metabolic effort. Based on this finding, Chapter 3 details the implementation of an EMG-based HIL optimization. The results demonstrated that minimizing RF activation in real-time successfully reduced physical effort without inducing compensatory movements. This confirmed that physiological personalization is feasible without cumbersome respiratory measurement equipment. Following the validation of the control algorithm, Chapters 4 and 5 detail the resolution of the second gap which is the development of a portable emulator system. While tethered lab systems can render any torque profile, they are immobile. Conversely, existing portable exoskeletons function primarily as simulators with fixed or limited stiffness profiles. To overcome this, Chapter 4 focuses on the mechanical evolution of a 3D printed modular AFO to ensure structural robustness and personalization capabilities. Subsequently, Chapter 5 presents the development of a high bandwidth Portable Actuation System (PAS). I developed a compact control unit that integrates powerful brushless DC motors, a real time industrial controller (Beckhoff SBC), and a custom EtherCAT and CAN communication bridge. Evaluation results confirmed a high control bandwidth of over 10 Hz. Although initial structural limitations were identified at torques exceeding 40 Nm, collaborative failure analysis and further design evolution with fellow researcher A. Patel successfully expanded the torque capacity to 80 Nm in a subsequent iteration. This established the hardware as a robust Portable Emulator capable of rendering high fidelity and laboratory quality assistance profiles in the field. Finally, Chapter 6 integrates the optimized control strategy and the portable hardware to demonstrate field deployment. To make the system more practical for outdoor environments, I adopted Heart Rate Variability (specifically RMSSD) derived from a wearable ECG sensor as a global cost function, replacing the multiple EMG sensors which can be intrusive. I conducted a field validation in a real-world hallway environment, where the portable system autonomously optimized assistance parameters during walking and squatting tasks. The on-device HIL optimization successfully converged to subject-specific parameters, and the validation results showed a strong positive trend in reducing metabolic cost compared to unpowered and generic conditions. In conclusion, this dissertation bridges the gap between theoretical robotic control and practical field application. By identifying a fast physiological proxy (Aim I), building a robust portable system (Aim II), and validating it in a real-world environment with wearable sensors (Aim III), this work establishes a comprehensive framework for industrially deployable personalized wearable robots"],"dc:identifier":["10.25417/uic.32995286.v1"],"dc:relation":["https://figshare.com/articles/thesis/Development_of_an_Industrially_Deployable_Personalized_Ankle_Foot_Orthosis_System/32995286"],"dc:rights":["In Copyright","Open Access after 2028-05-01"],"dc:subject":["Engineering, Robotics","Engineering, Mechanical"],"dc:title":["Development of an Industrially Deployable Personalized Ankle–Foot Orthosis System"],"dc:type":["Text","Thesis"]},"updated_at":"2026-07-27T21:33:53Z"}