Introducing elasticity in the mechanical design can endow robots with the ability of performing efficient and effective periodic motions. Yet, devising controllers that can take advantage of such elasticity is still an open challenge. This letter tackles an instance of this general problem, by proposing a control architecture for executing goal-oriented and efficient point-to-point periodic motions. This is achieved by (i) producing motor torques that excite intrinsic modal oscillations, and simultaneously (ii) adjusting parallel elasticity so to shape the natural modes. Analytical proofs of convergence are provided for the linear approximation. The performance and efficiency (in the sense of low energy expenditure) of the method in the nonlinear case are assessed with extensive simulations and experiments.

中文翻译：

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铰接式软机器人中高效且目标定向的振荡：点对点案例

在机械设计中引入弹性可以使机器人具有执行有效且有效的周期性运动的能力。然而，设计一种可以利用这种弹性的控制器仍然是一个开放的挑战。这封信通过提出一种用于执行面向目标且有效的点对点周期性运动的控制体系结构，解决了这一普遍问题的一个实例。这是通过（i）产生可激发固有模态振动的电机转矩，并同时（ii）调节平行弹性以形成自然模态来实现的。为线性近似提供了收敛的分析证明。通过广泛的仿真和实验评估了在非线性情况下该方法的性能和效率（就低能耗而言）。