Beyond the Cascade: Juggling Vanilla Siteswap Patterns

TL;DR

This paper advances robotic juggling by enabling the execution of complex mixed-height siteswap patterns, demonstrating successful simulation of various patterns and transitions, thus expanding the capabilities of robotic manipulation in dynamic tasks.

Contribution

It introduces a sequence planner and trajectory constraints for juggling mixed-height siteswap patterns, extending previous cascade-only analysis to more complex juggling sequences.

Findings

Successfully simulated 3-9 ball siteswap patterns

Achieved pattern transitions and random sequence juggling

Extended analysis to mixed-height juggling patterns

Abstract

Being widespread in human motor behavior, dynamic movements demonstrate higher efficiency and greater capacity to address a broader range of skill domains compared to their quasi-static counterparts. Among the frequently studied dynamic manipulation problems, robotic juggling tasks stand out due to their inherent ability to scale their difficulty levels to arbitrary extents, making them an excellent subject for investigation. In this study, we explore juggling patterns with mixed throw heights, following the vanilla siteswap juggling notation, which jugglers widely adopted to describe toss juggling patterns. This requires extending our previous analysis of the simpler cascade juggling task by a throw-height sequence planner and further constraints on the end effector trajectory. These are not necessary for cascade patterns but are vital to achieving patterns with mixed throw heights. Using a simulated environment, we demonstrate successful juggling of most common 3-9 ball siteswap patterns up to 9 ball height, transitions between these patterns, and random sequences covering all possible vanilla siteswap patterns with throws between 2 and 9 ball height. https://kai-ploeger.com/beyond-cascades