MicroRoboScope: A Portable and Integrated Mechatronic Platform for Magnetic and Acoustic Microrobotic Experimentation

TL;DR

MicroRoboScope addresses the need for portable, data-driven microrobotics experimentation by integrating magnetic and acoustic actuation with real-time video feedback in a compact, low-cost platform. It combines an Nvidia Jetson-based host, an Arduino-based actuator control, a microscope, and a Python/Arduino software stack to enable closed-loop control, tracking, and multi-modal actuation. The main contributions are (i) a compact 6-coil magnetic field system capable of uniform, gradient, and rotating fields, (ii) integrated acoustic actuation via a piezo transducer, (iii) a real-time tracking/ control GUI and data logging, and (iv) demonstrations of path following, manual manipulation, and dual actuation. The system lowers cost and barriers to entry, enabling education, field studies, and translational research in biomedicine and robotics.

Abstract

This paper presents MicroRoboScope, a portable, compact, and versatile microrobotic experimentation platform designed for real-time, closed-loop control of both magnetic and acoustic microrobots. The system integrates an embedded computer, microscope, power supplies, and control circuitry into a single, low-cost and fully integrated apparatus. Custom control software developed in Python and Arduino C++ handles live video acquisition, microrobot tracking, and generation of control signals for electromagnetic coils and acoustic transducers. The platform's multi-modal actuation, accessibility, and portability make it suitable not only for specialized research laboratories but also for educational and outreach settings. By lowering the barrier to entry for microrobotic experimentation, this system enables new opportunities for research, education, and translational applications in biomedicine, tissue engineering, and robotics.

Figures (8)

• Figure 1: a) Back, side, front, top and isometric views of computer aided design of device. b) Images of the physical system. The system measures 240 mm in the x-direction, 280 mm in the y direction, and 350 mm in the z-direction. These dimensions allow for all custom-made components, including the outer case, to be 3D printed on an Ender Max 3D printer. All electronics are housed inside the outer-case and accessible. c) Coil configuration with piezoelectric transducer and connections labeled. d) Computer aided design of the cross section of the device with important system components highlighted and defined.
• Figure 2: Flowchart of electrical system components. The Jetson AGX Orin communicates with an Arduino over serial to generate appropriate PWM (Pulse Width Modulation) signals. H-bridge circuits connected to an external power supply are used to switch the low current PWM signals from the arduino into high-current signals need to power the coils. The Arduino also interfaces with an ADS1115 analog to digital converter to read hall effect sensor data, as well as an AD9850 signal generator module to output high frequency sine waves needed to drive an piezoelectric transducer. Image feed from a microscope camera captures the workspace environment and used for tracking and detection of microrobots.
• Figure 3: Arduino Electrical Schematic of the System.
• Figure 4: a) Front-end software architecture developed using the PyQt5 library in Python, with tracking, viewing, and control tabs highlighted b) High-level back-end software architecture flowchart illustrating the main Python GUI processes and corresponding Arduino control loop functionality. Arduino and Python logos included to indicate software/hardware used. Logos are trademarks of their respective owners.
• Figure 5: a) Illustration of the spherical coordinate system used to define the axis of rotation of the rotating magnetic field, as described by equations (1–3). The axis orientation is controlled using the angles $\alpha$ and $\gamma$ parameters. Typically $\gamma = 90^{\circ}$ for 2D rolling motion. b) Schematic illustrating how a rotating magnetic field is synthesized using pulse-width modulation (PWM). The two plots show the resulting waveform formed by modulating the duty cycle (DC) of PWM signals over time. For the positive portion of the waveform (black sinusoid), the PWM signal is applied while the H-bridge is set to positive polarity (shown in blue). For the negative portion, the PWM is applied with the H-bridge in negative polarity (orange). The PWM signals effectively approximate the target sinusoidal waveform by varying the duty cycle from 0$\%$ to ±100$\%$. In this example, two sinusoidal waveforms are generated: the top signal is applied to the y-axis coils and the bottom to the x-axis coils, while the z-axis field is set to zero. This configuration creates a 1 Hz rotating magnetic field in the XY plane, as illustrated at the bottom. This is equivalent to setting $\gamma = 0^{\circ}$ using equations (1-3).