Silicon Odometers: Compact In Situ Aging Sensors for Robust System Design

Institutions are designed to alter human behavior. To remain effective over time, institutions need to adapt to changes in the environment or the society the institution is meant to regulate. Douglas North referred to this property as adaptive efficiency and suggested the need for a model of how institutions change to remain effective. This essay contributes to a theory of adaptive efficiency by relating it to the burgeoning literature in robust system design. It reviews five models of institutional change, paying particular attention to each model’s ability to explain institutional adaptation. It isolates three common structural features of a robust, adaptive institutional system: diversity, modularity, and redundancy. It illustrates the theory with a brief application to federal systems, and closes by describing some open research questions relating to institutional adaptive efficiency.

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Design and optimal control of a tiltrotor micro-aerial vehicle for efficient omnidirectional flight

The International Journal of Robotics Research ◽

10.1177/0278364920943654 ◽

2020 ◽

Vol 39 (10-11) ◽

pp. 1305-1325

Author(s):

Mike Allenspach ◽

Karen Bodie ◽

Maximilian Brunner ◽

Luca Rinsoz ◽

Zachary Taylor ◽

...

Keyword(s):

Optimal Control ◽

Design Optimization ◽

System Design ◽

Optimal Controller ◽

Micro Aerial Vehicle ◽

Aerial Vehicles ◽

Aerial Vehicle ◽

Robust System ◽

Six Degree Of Freedom ◽

Allocation Approach

Omnidirectional micro-aerial vehicles (MAVs) are a growing field of research, with demonstrated advantages for aerial interaction and uninhibited observation. While systems with complete pose omnidirectionality and high hover efficiency have been developed independently, a robust system that combines the two has not been demonstrated to date. This paper presents the design and optimal control of a novel omnidirectional vehicle that can exert a wrench in any orientation while maintaining efficient flight configurations. The system design is motivated by the result of a morphology design optimization. A six-degree-of-freedom optimal controller is derived, with an actuator allocation approach that implements task prioritization, and is robust to singularities. Flight experiments demonstrate and verify the system’s capabilities.

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