U2sonobot-vers 2

An untethered ultrasonic robot (U2sonobot) operating in resonant vibration is developed by integrating dual transducers, an onboard circuit, and a battery. Here, the longitudinal and bending vibrations lead to the out-of-phase swing motion and the alternating acceleration, respectively; these imitate the rotatory galloping gait in terms of the driving feet’s movement pattern and the operating sequence. First, the transducers were designed to gather the resonant frequencies of two vibrations and produce the same node for steadily supporting the other components. Second, an onboard circuit was devised to convert the 3.7 V battery’s DC signal into multi-channels of ultrasonic signals via multi-level amplification. Third, a prototype 54 × 52 × 46 mm3 in size and 76.5 g in weight was fabricated to assess its moving/carrying performance. At 59.3 kHz frequency, U2sonobot yielded the maximal speed of 221 mm/s and the minimal step displacement of 0.3 μm. According to the wirelessly-received commands, it produced various types of flexible movements (e.g., those with adjustable speed/steering-radii and in-situ rotations) and climbed 8.9° slope. Moreover, it carried the maximal payload of 520 g and provided the minimal cost of transport of 3.9. U2sonobot accomplishes fast and load-carriable movements, implying its potentially applicability to optical focusing/scanning system.

本研究通过集成双换能器、板载电路与电池，研制出一款采用谐振振动工作模式的无系绳超声波机器人（U2sonobot）。该机器人的纵向振动与弯曲振动分别驱动产生异相摆动运动与交变加速度，其驱动足的运动模式与工作时序模仿了旋转驰振步态。其一，换能器的设计目标为获取两种振动的谐振频率，并生成同一振动节点以稳定支撑其余组件；其二，板载电路可通过多级放大将3.7 V电池的直流信号转换为多通道超声波信号；其三，研制了尺寸为54×52×46 mm³、重量为76.5 g的样机，以测试其运动与负载性能。在59.3 kHz的工作频率下，U2sonobot实现了221 mm/s的最大运动速度与0.3 μm的最小步移量。根据无线接收的控制指令，该机器人可实现多种灵活运动模式，例如可调速运动、可调转向半径运动及原地旋转动作，并可攀爬8.9°的斜坡。此外，其最大有效负载可达520 g，最小运输成本为3.9。U2sonobot可实现高速且具备负载能力的运动，表明其在光学聚焦/扫描系统中具备潜在应用价值。