Shake tables provide a critical tool for simulating earthquake events and testing the response of structures to seismic forces. However, existing shake tables are either expensive or proprietary. This paper presents the design and implementation of a low-cost, open-source shake table named Shakebot for earthquake engineering research and education, built using Robot Operating System (ROS) and robotic concepts. The Shakebot adapts affordable and high-accuracy components from 3D printers, particularly a closed-loop stepper motor for actuation and a toothed belt for transmission. The stepper motor enables the bed to reach a maximum horizontal acceleration of 11.8 m/s^2 (1.2 g), and velocity of 0.5 m/s, with a 2 kg specimen. The Shakebot is equipped with an accelerometer and a high frame-rate camera for bed motion estimation. The low cost and easy use make the Shakebot accessible to a wide range of users, including students, educators, and researchers in low-resource settings. An important application of the Shakebot is to examine the dynamics of precariously balanced rocks (PBRs), which are negative indicators of earthquakes in nature. Our earlier research built a virtual shake robot in simulation for the PBR study. The Shakebot provides an approach to validate the simulation through physical experiments. The ROS-based perception and motion software facilitates the code transition from our virtual shake robot to the physical Shakebot. The reuse of the control programs ensures that the implemented ground motions are consistent for both the simulation and physical experiments, which is critical to validate our simulation experiments.

翻译：振动台为模拟地震事件及测试结构对地震力的响应提供了关键工具，然而现有振动台设备或成本高昂，或为专有设计。本文介绍了一种名为Shakebot的低成本开源振动台的设计与实现，该振动台基于机器人操作系统（ROS）及机器人概念构建，专用于地震工程研究与教育。Shakebot采用了从3D打印机中改造的经济型高精度组件，特别是使用闭环步进电机作为驱动单元，同步带作为传动机构。该步进电机可使台面在承载2千克试件时达到11.8 m/s²（1.2 g）的最大水平加速度和0.5 m/s的最大速度。Shakebot配备有加速度计和高速摄像机，用于台面运动估计。低成本与易用性使得Shakebot能够被广泛用户群体所使用，包括资源有限环境下的学生、教育工作者和研究人员。Shakebot的一个重要应用是研究危险平衡岩石（PBRs）的动力学特性，这类岩石是自然界中地震的负指标。我们先前的研究已在仿真环境中构建了一个用于PBR研究的虚拟振动台机器人。Shakebot提供了一种通过物理实验验证仿真的途径。基于ROS的感知与运动控制软件架构促进了从虚拟振动台机器人到物理Shakebot的代码迁移。控制程序的重用确保了仿真与物理实验中所施加地面运动的一致性，这对于验证我们的仿真实验结果至关重要。