maru: a miniature-sized wheeled robot for swarm robotics research
maru
"maru" (= miniature assemblage adaptive robot unit) is a custom-made, miniature-sized, two-wheeled robot designed specifically for tabletop swarm robotics research. This platform enables researchers and hobbyists to explore the dynamics of swarm robotics in a controlled, tabletop environment.
The GitHub repository serves as a comprehensive resource for assembling and operating maru, providing detailed documentation and files, including:
hardware/3Dmodel3D models of the robot and its cradle (a combined communication and charging module),hardware/circuit/schematicCircuit schematics to guide the electronic assembly,hardware/circuit/gerberGerber files for PCB manufacturing,software/firmware Firmwarefor both the robot and the cradle, distributed in binary format (Note: There are currently no plans to release the source code),software/controlAPIs and sample codes to help you get started with programming the robot for various tasks and behaviors (C# and Python).
This project draws inspiration from Zooids, an open-source swarm robot platform. Similar to Zooids, maru employs projection-based position tracking; however both maru's hardware and software are entirely new designs, another platform for swarm robotics research in HCI.
Hardware
The hardware design is shown above. The dimensions are 30 mm in diameter and 34 mm in height, weighing about 23 g. The robot parts include a microcontroller unit (STM32G071KBU62 from STMicroelectronics), motor drivers (DRV8837DSGR3 from Texas Instruments), RF module (RF2401F204 from NiceRF), motors with a 26:1 planetary gearbox (Pololu 23575), photodiode (PD15-22C/TR86 from Everlight Electronics), and a 40mAh Li-Po battery.
Since the robot is lightweight, the robot may fall over while moving if the moving speed is too fast. Magnets can be attached to the bottom of the robot, and the robot can be run on steel or other materials to keep it from falling over.
A detailed description of the hardware design and specifications is available here.
Software
The communication between the robots and the host computer is shown above. The robots and the cradles (charging station + RF/IO dongle) are each equipped with an RF module and communicate through a 2.4GHz ISM band wireless communication. The user does not need to be aware of the communication control between the robot and the cradles, as it is performed on the firmware of both devices. The user can easily control the robot wirelessly by sending the specified commands.
A detailed description of the software design and specifications is available here.
Projection-based Localization
A projection-based localization system used for the Zooids was used to track the robots. A high-speed projector (DLP LightCrafter 4500 from Texas Instruments) was used to project a sequence of gray-coded patterns onto the table; the two photodiodes on the robot received the projected coded-pattern light, and the microcontroller of the robot decoded its pattern into position information. Then, the robot calculated its orientation from the positions of two photodiodes and broadcasted its position and orientation information to the host computer.
For instructions on the projector tracking system, see Zooids documentation.
License
The software materials of this project are under an MIT license.
The hardware materials of this project are under a Creative Commons Attribution 4.0 International License.
Contact
This is a joint work between OMRON SINIC X Corporation, Cluster Metaverse Lab, and karakuri products, inc. If you prefer purchasing pre-assembled robots instead of assembling them yourself, please contact karakuri products, inc.
Citation
maru was first introduced and used in the following paper:
@inproceedings{ichihashi2024swarm,
author = {Ichihashi, Sosuke and Kuroki, So and Nishimura, Mai and Kasaura, Kazumi and Hiraki, Takefumi and Tanaka, Kazutoshi and Yoshida, Shigeo},
title = {Swarm Body: Embodied Swarm Robots},
year = {2024},
publisher = {Association for Computing Machinery},
address = {New York, NY, USA},
url = {[https://doi.org/10.1145/3613904.3642870](https://doi.org/10.1145/3613904.3642870)},
doi = {10.1145/3613904.3642870},
booktitle = {Proceedings of the 2024 CHI Conference on Human Factors in Computing Systems},
numpages = {19},
location = {, Honolulu, HI, USA, },
series = {CHI '24}
}
Projects powered by maru
maru is used across diverse fields, including not only HCI applications but also Robotics and Machine Learning.
