ERI: Soft Robotic Musculoskeletal Manipulation for Pain Reduction

The opioid crisis is a national health emergency and has led to a six-fold increase in drug overdoses over the past 25 years. Opioid pain medications are very addictive; thus, the CDC recommends non-pharmacological approaches as the first course of action for pain management. Chronic musculoskeletal pain affects over 40 percent of US citizens. Musculoskeletal manipulation has proven effective at treating many types of pain but requires a human to perform costly, labor-intensive therapy. This Engineering Research Initiation (ERI) grant will support fundamental research in the development of soft robotic devices that can be pneumatically actuated to perform musculoskeletal manipulation for targeted pain relief. The human-robot interaction required for such therapy involves a large amount of physical contact; therefore, safety becomes a large design requirement. Current humanoid rigid robots can perform a variety of tasks. However, this ability to generalize gives them the freedom to be unsafe for physically therapeutic applications. This research aims to produce highly constrained, targeted soft devices with mechanical safety limits that are individually customized to each individual’s anatomy and pain pathologies which may range from back pain to arthritis to post-stroke hand spasticity. Besides the societal impact of pain reduction, this research will contribute to fundamental advances in soft robotic design, scalable customization, soft additive manufacturing, flexible electronics, sensor design, physics-based simulations, mechatronics, pneumatics, interactive control, and data-driven modeling. Student researchers will benefit from this applied, multidisciplinary problem space, rich with complex challenges, which can inspire a passion for future careers in various mechanical engineering, electrical engineering, robotics, and data science disciplines. This grant is about enabling autonomous delivery of musculoskeletal therapy through the development of customized soft robotic systems that can safely and effectively interact with the human body. The research effort consists of several tightly integrated components that span sensing, modeling, design, and control. At the core of the approach is the development of soft, stretchable e-skin sensors with dense pressure arrays, created using novel flexible electronics and soft additive manufacturing techniques. These sensors will be applied to pain-affected regions of participants to capture high-resolution force and motion data during therapist-administered manual manipulations. This data, along with detailed 3D scans of each participant, will be used to construct high-fidelity physics-based simulations that replicate therapist-patient interaction. These simulations serve as the foundation for optimizing soft robotic designs and pneumatic actuation profiles using evolutionary algorithms. Each design will be customized to the user’s specific anatomy and pain condition, whether it involves back pain, arthritis, or post-stroke spasticity. The optimized robotic structures will be fabricated through soft 3D printing processes and integrated with pneumatic control systems. During therapy, the same e-skin sensors will be reused to provide real-time force and position feedback. This feedback will drive closed-loop control strategies that look to combine physics-based and data-driven models of the human-robot system. The goal is to achieve safe and adaptive manipulation that can respond to the user’s changing physical state. Overall, this research contributes to fundamental advances in soft robotics, personalized therapeutic devices, human-robot interaction, and intelligent control systems. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.