Passive dynamic walkers are widely adopted as a mathematical model to represent biped walking. The stable locomotion of these models is limited to tilted surfaces, requiring gravitational energy. Various techniques, such as actuation through the ankle and hip joints, have been proposed to extend the applicability of these models to level ground and rough terrain with improved locomotion efficiency. However, most of these techniques rely on impulsive energy injection schemes and torsional springs, which are quite challenging to implement in a physical platform. Here, a new model is proposed, named triggering controlled ankle actuated compass gait (TC-AACG), which allows non-instantaneous compliant ankle pushoff. The proposed technique can be implemented in physical platforms via series elastic actuators (SEAs). Our systematic examination shows that the proposed approach extends the locomotion capabilities of a biped model compared to impulsive ankle pushoff approach. We provide extensive simulation analysis investigating the locomotion speed, mechanical cost of transport, and basin of attraction of the proposed model.

翻译：被动动态行走器被广泛用作表示双足行走的数学模型。这些模型的稳定运动仅限于倾斜表面，需要重力势能驱动。已有多种技术被提出以扩展这些模型在水平地面和崎岖地形上的适用性并提升运动效率，例如通过踝关节和髋关节进行驱动。然而，大多数技术依赖于脉冲能量注入方案和扭力弹簧，这在物理平台上实现极具挑战性。本文提出了一种名为触发控制踝关节驱动双足步态的新模型，该模型允许非瞬时性的柔性踝关节蹬地动作。所提出的技术可通过串联弹性执行器在物理平台上实现。系统化研究表明，与脉冲式踝关节蹬地方法相比，该方法扩展了双足模型的运动能力。我们通过大量仿真分析，探究了所提出模型的运动速度、机械运输成本和吸引域特性。