Frequency-selective wireless power transfer provides a feasible route to enable independent actuation and control of multiple untethered robots in a common workspace; however, the scalability remains unquantified, particularly the maximum number of resonators that can be reliably addressed within a given frequency bandwidth. To address this, we formulate the relationship between resonator quality factor (Q-factor) and the number of individually addressable inductor-capacitor (LC) resonant energy harvesters within a fixed radio-frequency (RF) spectrum, and we convert selectively activated harvested energy into mechanical motion. We theoretically proved and experimentally demonstrated that scalability depends primarily on the Q-factor. For this proof-of-concept study, we define effective series resistance as a function of frequency allocating bandwidths to discrete actuators. We provide design equations for scaling untethered magnetic actuation with Q-factor optimization. Resonator networks spanning bandwidths from 100kHz to 1MHz were analyzed to quantify how increasing the number of resonators affects independent addressability. We validated the approach experimentally by fabricating three centimeter-scale untethered actuators that selectively trigger the motion of mechanical beams at 734kHz, 785kHz, and 855kHz. We also characterized the generated mechanical force and the activation bandwidth of each actuator, confirming that no unintended cross-triggering occurred.

翻译：频率选择性无线功率传输为在共享工作空间中实现多个无束缚机器人的独立驱动与控制提供了可行途径；然而，其可扩展性尚未量化，尤其是在给定频率带宽内可可靠寻址的谐振器最大数量。针对此问题，我们建立了谐振器品质因数（Q值）与固定射频频谱内可独立寻址的电感-电容（LC）谐振能量采集器数量之间的关系，并将选择性激活的能量转化为机械运动。我们从理论上证明并通过实验验证了可扩展性主要取决于Q值。在本概念验证研究中，我们将有效串联电阻定义为频率的函数，据此为离散执行器分配带宽。我们提供了通过优化Q值实现可扩展无束缚磁驱动的设计方程。对跨度为100kHz至1MHz带宽的谐振器网络进行了分析，以量化增加谐振器数量对独立寻址能力的影响。我们通过实验验证了该方法，制备了三个厘米级无束缚执行器，分别在734kHz、785kHz和855kHz频率下选择性触发机械梁的运动。同时，我们表征了每个执行器产生的机械力与激活带宽，确认未发生意外的交叉触发。