Comparative Design, Scaling, and Control of Appendages for Inertial Reorientation

Abstract

This paper develops a comparative framework for the design of actuated inertial appendages for planar, aerial reorientation. We define the Inertial Reorientation template, the simplest model of this behavior, and leverage its linear dynamics to reveal the design constraints linking a task with the body designs capable of completing it. As practicable inertial appendage designs lead to morphology that is generally more complex, we advance a notion of "anchoring" whereby a judicious choice of physical design in concert with an appropriate control policy yields a system whose closed loop dynamics are sufficiently captured by the template as to permit all further design to take place in its far simpler parameter space. This approach is effective and accurate over the diverse design spaces afforded by existing platforms, enabling performance comparison through the shared task space. We analyze examples from the literature and find advantages to each body type, but conclude that tails provide the highest potential performance for reasonable designs. Thus motivated, we build a physical example by retrofitting a tail to a RHex robot and present empirical evidence of its efficacy.

Analytically-Guided Design of a Tailed Bipedal Hopping Robot

“…II) can be generalized to other high DoF platforms, ultimately generalizing the precision of the morphological reduction analysis introduced for a 1 DoF template in [23]. Even though the Jerboa is a specialized machine, inertial coupling between degrees of freedom is used for control in a variety of robotic platforms [23,34], and an analytical result as in Sec. II-B.5 may help the control designer tune the effectiveness of this sort of coupling at design-or control-time.…”

“…Specifically, in this paper, we take initial steps toward a formal morphological reduction [23] of the 4 actuator, 12 DoF Jerboa robot onto the 1 actuator, 2 DoF TVH template by using hybrid averaging [7,24] to project the large and unintuitive 1 parameter space of the Jerboa onto its equilibrium hopping height, our candidate metric of hopping performance (13). In so doing, we (a) enable selection of control gains for metrically accurate hopping height control ( Fig.…”

Soft‐Robotik

“…Die Biologie spielt eine übermäßig große Rolle in der Zukunft des Gebiets, sowohl in den biomedizinischen Anwendungen, als auch als Quelle für unzählige Beispiele an funktionellen Soft‐Strukturen, die man als Basis für neue Klassen an robotischen Systemen benutzen kann . Am Beispiel “Füße” sieht man, dass Tiere und Insekten eine enorme Anzahl an Strategien verwenden, um eine Bewegung über Oberflächen zu ermöglichen, von Wasser bis zur Zimmerdecke; diese Strategien beruhen normalerweise auf den Eigenschaften von nachgiebigen biologischen Strukturen. Die Liste an interessanten biologischen Strukturen (Federn, Schuppen, Knochen, Blutgefäße, Augen, Muskeln, Nerven, Tentakel, fluidische Pumpen und Prozessoren usw.)…”

An Active Stabilizer for Cable-Driven Parallel Robot Vibration Damping

“…Besides, in [18], actuated rotating arms are used to adjust the position of the center of mass of a static 6-DOF nonactuated platform. The same type of actuator can be used to generate inertial forces for dynamic reorientation as in [19]. Several can be coupled together to generate forces and torques along more than one directions [20], allowing more complex control strategies.…”