Abstract Compared with the catapult mechanism widely employed by small jumping robots, recently proposed jumping strategies based on series-elastic actuators (SEA) without latch mechanisms perform better in terms of agility, structural robustness and maneuverability. However, in some practical applications, they have difficulty in effectively storing energy before the push-off. This paper presents a novel no-latch jumping strategy inspired by frogs, achieving highly effective energy storage. The jumping strategy combines an SEA with a parallel-elastic linkage, which allows one motor to rotate in one direction to store the elastic energy and automatically trigger its release. Combined with this strategy, a frog-inspired robotic leg mechanism is designed. The jumping process is analysed in detail and the kinematic and dynamic models are derived. Bars’ dimensions and springs’ parameters are determined by the optimization to maximize the energy-storing capacity. The simulation is performed to predict the jumping performance. A 100.7 g prototype is fabricated and jumps to a height of 1.3 m with slight aerial body rotation. The energy-storing capacity of the robot is 18.1 J/Kg.

中文翻译：

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一种组合的串联弹性执行器和并联弹性腿无闩锁仿生跳跃机器人

摘要 与小型跳跃机器人广泛采用的弹射机构相比，最近提出的基于串联弹性致动器（SEA）的无闩锁机构的跳跃策略在敏捷性、结构鲁棒性和机动性方面表现更好。然而，在一些实际应用中，它们在推出前难以有效储存能量。本文提出了一种受青蛙启发的新型无闩锁跳跃策略，实现了高效的能量存储。跳跃策略将 SEA 与平行弹性联动装置相结合，允许一个电机向一个方向旋转以存储弹性能量并自动触发其释放。结合这种策略，设计了一种受青蛙启发的机器人腿机构。详细分析了跳跃过程，推导出了运动学和动力学模型。杆的尺寸和弹簧的参数由优化确定以最大化能量存储能力。执行模拟以预测跳跃性能。制造了一个 100.7 g 的原型，并在空中身体轻微旋转的情况下跳到 1.3 m 的高度。机器人的储能能力为18.1 J/Kg。