Repetitive extreme-acceleration (14-g) spatial jumping with Salto-1P

In this work we present a new robotic system, Salto-1P, for exploring extreme jumping locomotion. Salto-1P weighs 0.098 kg, and has an active leg length of 14.4 cm. The robot is able to perform a standing vertical leap of 1.25 m, continuously hop to heights over 1 m, and jump over 2 m horizontally. Salto-1P uses aerodynamic thrusters and an inertial tail to control its attitude in the air. A linearized Raibert step controller was sufficient to enable unconstrained in-place hopping and forwards-backwards locomotion with external position feedback. We present studies of extreme jumping locomotion in which the robot spends just 7.7% of its time on the ground, experiencing accelerations of 14 times earth gravity in its stance phase. An experimentally collected dataset of 772 observed jumps was used to establish the range of achievable horizontal and vertical impulses for Salto-1P.

I. Introduction

Saltatorial animals (animals that locomote by jumping) such as bushbabies can move through complex, usually arboreal environments by chaining together large (over 2 meter) jumps. This saltatorial mode of locomotion is interesting for robotics because it enables rapid movement through complex terrain and added flexibility for how the robot interacts with the environment. The farther a robot can jump the better it can discretize its environment, clearing larger gaps and obstacles and making path-planning easier [7]. Prior work has shown that a robot that can perform two high-amplitude jumps in succession was able to spring off a wall to gain energy and height [12]. A robot proficient at saltatorial locomotion would be able to move through its environment in new and previously insupposable ways.