Session: ASME Undergraduate Student Design Expo

Paper Number: 175561

Development of a Six-Axis Robotic Arm With Embedded Control for Safe Medical Plasma Therapy in Biomedical Applications 

Cold Plasma Therapy has shown effectiveness in enhancing the wound healing process in addition to preventing infection with its antimicrobial and tissue regenerative effects.  Despite these benefits, its clinical adoption remains limited since treatment efficacy is dependent on precise exposure conditions. The plasma-to-probe distance from the wound, duration of exposure, and uniformity over the surface must be carefully maintained to avoid damaging tissue or ineffective sterilization. In practice, manual handling of plasma probes cannot guarantee these requirements, especially when wounds consist of irregular geometries. This gap highlights the need for an automated, precise, and adaptive delivery system. Our hypothesis is that a robotic arm having a multi degree-of-freedom movement can be employed to have a uniform operation over both the flat and curved wound surfaces, providing safer and more consistent therapy.

The scientific contribution of this work lies in its integration of robotics, embedded systems, and medical engineering into a single device designed specifically for plasma-based wound treatment. Unlike off-the-shelf robotic solutions, which are often expensive and lack modularity to scale in clinics, our system was built from the ground up to balance precision, modularity, and cost-effectiveness. Each major mechanical component was designed in SolidWorks and manufactured using 3D printing to allow rapid prototyping. Testing The arm architecture emphasizes modularity to support future device upgrades and reconfiguration for diverse biomedical and industrial plasma applications.

The engineering process included a multi-domain design and analysis. Torque and stability calculations were used to derive mechanical requirements that were used to guide actuator selection. Closed through NEMA 17 stepper motors in combination with stepper motors with backlash-resistant gearboxes were to be used to provide up to 4.5 Nms of torque at the high-load joints, thus providing stable operation during dynamic motion. Mechanical stops and software level safety limits were added in order to reduce the possibility of unforeseen motion. On the control side, a dual-tier design clearly divides the roles: a Teen-si 4.1 microcontroller offers high-frequency, real-time motion control, and a Raspberry 5 is used in trajectory generation, coordination of the system and user interfacing. This separation allows accuracy at the low level hardware interface and versatility at the upper level control interface. Blended trajectory-planning algorithms enable the probe to track wound contours without any abrupt transitions but with a constant standoff distance and constant orientation.

 

The initial experimental tests have shown that the robotic system can perform repeatable scanning movements [20 inch max scan radius with Zmax about 25 inches], sustain a constant torch position, and provide the smooth delivery of the plasma along different edges. These preliminary findings confirm the practicability of robotic control in wound-treatment, with the accuracy of the path and the deviation of the programmed tool paths being minimal. Notably, the qualitative analyses have shown enhanced consistency over hand tools, which highlights clinical potential of the system. The fabrication method that involves rigidity coupled with weight optimisation further makes the robot portable and clinically adaptable.

 

To sum up, the presented project adds a new robotic platform in cold plasma treatment that can prove that wound-care operations may be less harmful and reproducible. In addition to direct biomedical uses, the embedded-systems form and modular design of the platform ensure that it can be extended to other plasma-based processes in the industrial or laboratory setting. Future efforts will involve testing of quantitative wound-treatment models, closed-loop feedback with sensor integration and future clinical collaborations. These findings show the extent to which interdisciplinary design, which is a combination of mechatronics, control, and biomedical engineering, can be used to respond to urgent medical demands with scalable robotic solutions.

Presenting Author: Aayushya Patel IntelliScience Institute

Presenting Author Biography: Currently working as an volunteer internship at San Jose State University, Department of Mechanical Engineering. My research involves robotics, automation, and their applications in the medical field. After graduating from my school, I intend to continue work in this direction.

Authors:

Sohail Zaidi San Jose State University
Aayushya Patel IntelliScience Institute