We characterise the diffusion, mean-square speed, mean-square angular displacement, radial and speed probability distributions of toy robots called ‘hexbugs-nano’ that move on a dish antenna (with added surface roughness) simulating a harmonic well. It is observed that a model considering the system’s translational inertia but neglecting its moment of inertia, together with the inclusion of a constant external torque in the orientational motion, suffices to describe the robots’ dynamics. Langevin dynamics simulation are also performed and a good agreement between theory, simulations and experiments is observed.

中文翻译：

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被困主动玩具机器人：理论与实验

我们描述了被称为“hexbugs-nano”的玩具机器人的扩散、均方速度、均方角位移、径向和速度概率分布，这些机器人在模拟谐波井的碟形天线（增加了表面粗糙度）上移动。据观察，一个考虑系统平移惯性但忽略其惯性矩的模型，连同在定向运动中包含恒定外部扭矩，足以描述机器人的动力学。还进行了朗之万动力学模拟，并观察到理论、模拟和实验之间的良好一致性。