Fabrication of a Sensing Structure on the sAFAM Microrobot

Student’s name: Esau Guadalupe Home Institution: Columbus State University NNCI Site: KY Multiscale @ University of Louisville REU Principal Investigator: REU Mentors: Daniel Sills, Andriy Sherehiy, Dan Popa Abstract: One of the main challenges in microrobotics is control of the miniature robots at the microscale. For this reason, awareness of the robot’s behavior is critical. Robot’s are usually monitored and directed with the help of optical or electron microscopy systems. However this approach has disadvantages due to the extended response times and complexity of the custom control system. The solution is a sensor integrated with the body of the microrobot where nano-microscopic size of features requires application of the cleanroom techniques. In this paper we propose the fabrication method of the sensor structure for the microscale robot utilizing additive manufacturing method Aerosol Jet Printing (AJP). As a testing device we chose solid Articulated Four Axis Microrobot (sAFAM) designed for the nano/microscale manipulation. Sensor’s structure consists of the insulating (bottom) and piezoresistive sensing (top) layer. Insulating layer is fabricated in the cleanroom using Atomic Layer Deposition (ALD) and the piezoresistive part is printed using AJP and PEDOT:PSS ink. Since some of the microrobot’s components experience mechanical deformation during the operation, we can utilize the piezoresistivity effect to detect and assess motion of the robot’s part. Precise printing and inspection is conducted with the help of the Nexus system, a large robotic system integrating various additive manufacturing tools and enabling automated multiscale manufacturing of custom devices. Fabricated sensing structures were tested and evaluated. Proposed manufacturing method offers a simpler and low-cost solution compared to MEMS techniques. Collected experience and further development could lead to the establishing novel advanced manufacturing methods enabling integration of the multiscale devices.