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Operations Research, Systems Engineering and Industrial Engineering Commons

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Articles 1 - 7 of 7

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Leg Design For Energy Management In An Electromechanical Robot, Gavin Kenneally Sep 2015

Leg Design For Energy Management In An Electromechanical Robot, Gavin Kenneally

Departmental Papers (ESE)

This paper examines the design of a parallel spring-loaded actuated linkage intended for dynamically dexterous legged robotics applications. Targeted at toe placement in the sagittal plane, the mechanism applies two direct-drive brushless dc motors to a symmetric five bar linkage arranged to power free tangential motion and compliant radial motion associated with running, leaping, and related agile locomotion behaviors. Whereas traditional leg design typically decouples the consideration of motor sizing, kinematics and compliance, we examine their conjoined influence on three key characteristics of the legged locomotion cycle: transducing battery energy to body energy during stance; mitigating collision losses upon toe ...


A Drift-Diffusion Model For Robotic Obstacle Avoidance, Paul B. Reverdy, B. Deniz Ilhan, Daniel E. Koditschek Aug 2015

A Drift-Diffusion Model For Robotic Obstacle Avoidance, Paul B. Reverdy, B. Deniz Ilhan, Daniel E. Koditschek

Departmental Papers (ESE)

We develop a stochastic framework for modeling and analysis of robot navigation in the presence of obstacles. We show that, with appropriate assumptions, the probability of a robot avoiding a given obstacle can be reduced to a function of a single dimensionless parameter which captures all relevant quantities of the problem. This parameter is analogous to the Peclet number considered in the literature on mass transport in advection-diffusion fluid flows. Using the framework we also compute statistics of the time required to escape an obstacle in an informative case. The results of the computation show that adding noise to the ...


Semi-Autonomous Exploration Of Multi-Floor Buildings With A Legged Robot, Garrett Wenger, Aaron Johnson, Camilo Jose Taylor, Daniel E. Koditschek May 2015

Semi-Autonomous Exploration Of Multi-Floor Buildings With A Legged Robot, Garrett Wenger, Aaron Johnson, Camilo Jose Taylor, Daniel E. Koditschek

Departmental Papers (ESE)

This paper presents preliminary results of a semi-autonomous building exploration behavior using the hexapedal robot RHex. Stairwells are used in virtually all multi-floor buildings, and so in order for a mobile robot to effectively explore, map, clear, monitor, or patrol such buildings it must be able to ascend and descend stairwells. However most conventional mobile robots based on a wheeled platform are unable to traverse stairwells, motivating use of the more mobile legged machine. This semi-autonomous behavior uses a human driver to provide steering input to the robot, as would be the case in, e.g., a tele-operated building exploration ...


Parallel Composition Of Templates For Tail-Energized Planar Hopping, Avik De, Daniel E. Koditschek May 2015

Parallel Composition Of Templates For Tail-Energized Planar Hopping, Avik De, Daniel E. Koditschek

Departmental Papers (ESE)

We have built a 4DOF tailed monoped that hops along a boom permitting free sagittal plane motion. This underactuated platform is powered by a hip motor that adjusts leg touchdown angle in flight and balance in stance, along with a tail motor that adjusts body shape in flight and drives energy into the passive leg shank spring during stance. The motor control signals arise from the application in parallel of four simple, completely decoupled 1DOF feedback laws that provably stabilize in isolation four corresponding 1DOF abstract reference plants. Each of these abstract 1DOF closedloopdynamicsrepresentssomesimplebutcrucialspecific component of the locomotion task at ...


Tail-Assisted Rigid And Compliant Legged Leaping, Anna Brill, Avik De, Aaron Johnson, Daniel E. Koditschek Jan 2015

Tail-Assisted Rigid And Compliant Legged Leaping, Anna Brill, Avik De, Aaron Johnson, Daniel E. Koditschek

Departmental Papers (ESE)

This paper explores the design space of simple legged robots capable of leaping culminating in new behaviors for the Penn Jerboa, an underactuated, dynamically dexterous robot. Using a combination of formal reasoning and physical intuition, we analyze and test successively more capable leaping behaviors through successively more complicated body mechanics. The final version of this machine studied here bounds up a ledge 1.5 times its hip height and crosses a gap 2 times its body length, exceeding in this last regard the mark set by the far more mature RHex hexapod. Theoretical contributions include a non-existence proof of a ...


Robotic Measurement Of Aeolian Processes, Sonia Roberts, Douglas J. Jerolmack, Nick Lancaster, George Nikolich, Paul B. Reverdy, Thomas F. Shipley, Scott Van Pelt, Ted Zobeck, Daniel E. Koditschek Jan 2015

Robotic Measurement Of Aeolian Processes, Sonia Roberts, Douglas J. Jerolmack, Nick Lancaster, George Nikolich, Paul B. Reverdy, Thomas F. Shipley, Scott Van Pelt, Ted Zobeck, Daniel E. Koditschek

Departmental Papers (ESE)

Measurements used to study wind shear stress and turbulence, surface roughness, sand flux, and dust emissions are typically obtained from stationary instrumentation, and are thus limited spatially. They are also dependent on deployment of instrumentation for specific events and thus the are limited temporally. We have been adapting a rough-terrain legged robot capable of rapidly traversing desert terrain to serve as a semi-autonomous, reactive mobile sensory platform (RHex [1]), which would not share these limitations. We report on early trials of the robotic platform at the Jornada LTER and White Sands National Monument to test the feasibility of gathering measurements ...


Averaged Anchoring Of Decoupled Templates In A Tail-Energized Monoped, Avik De, Daniel E. Koditschek Jan 2015

Averaged Anchoring Of Decoupled Templates In A Tail-Energized Monoped, Avik De, Daniel E. Koditschek

Departmental Papers (ESE)

We refine and advance a notion of parallel composition to achieve for the first time a stability proof and empirical demonstration of a steady-state gait on a highly coupled 3DOF legged platform controlled by two simple (decoupled) feedback laws that provably stabilize in isolation two simple 1DOF mechanical subsystems. Specifically, we stabilize a limit cycle on a tailed monoped to excite sustained sagittal plane translational hopping energized by tail-pumping during stance. The constituent subsystems for which the controllers are nominally designed are: (i) a purely vertical bouncing mass (controlled by injecting energy into its springy shaft); and (ii) a purely ...