Design and integration of a drone based passive manipulator for capturing flying targets

SUMMARY In this paper, we present a novel passive single degree-of-freedom (DoF) manipulator design and its integration on an autonomous drone to capture a moving target. The end-effector is designed to be passive, to disengage the moving target from a flying UAV and capture it efficiently in the presence of disturbances, with minimal energy usage. It is also designed to handle target sway and the effect of downwash. The passive manipulator is integrated with the drone through a single DoF arm, and experiments are carried out in an outdoor environment. The rack-and-pinion mechanism incorporated for this manipulator ensures safety by extending the manipulator beyond the body of the drone to capture the target. The autonomous capturing experiments are conducted using a red ball hanging from a stationary drone and subsequently from a moving drone. The experiments show that the manipulator captures the target with a success rate of 70% even under environmental/measurement uncertainties and errors.

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Using K’NEX to Understand and Teach Concepts in Movement Biomechanics

ASME 2010 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2010-19590 ◽

2010 ◽

Author(s):

Steven Charles

Keyword(s):

Lower Limb ◽

Reference Frames ◽

Human Motion ◽

The Body ◽

Single Degree Of Freedom ◽

Generalized Coordinates ◽

Single Degree ◽

Fixed Reference ◽

Time To Learn ◽

And Robotics

In order to analyze the kinematics or model the dynamics of human motion, one must be able to abstract from the intricate anatomy of the body the mechanical linkages and kinematic constraints which best approximate the joints of the body. Given the number and complexity of joints in the human body, this abstraction can be a challenging task, especially for students. While rotations about a single degree of freedom are easy to grasp, rotations about multiple DOF, which occur commonly throughout the body (e.g. shoulder, wrist, ankle, etc.) are anything but trivial. Likewise, the kinematics or dynamics of mechanical linkages such as the upper or lower limb quickly become unwieldy. To deal with these challenges, students learn to use tools from mechanics and robotics (body- and space-fixed reference frames, transformations, generalized coordinates, etc.), but these concepts can themselves be challenging and certainly take time to learn.

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Three-Position Synthesis of Origami-Evolved, Spherically Constrained Spatial Revolute–Revolute Chains

Journal of Mechanisms and Robotics ◽

10.1115/1.4030370 ◽

2015 ◽

Vol 8 (1) ◽

Cited By ~ 4

Author(s):

Kassim Abdul-Sater ◽

Manuel M. Winkler ◽

Franz Irlinger ◽

Tim C. Lueth

Keyword(s):

Building Blocks ◽

Design Parameters ◽

Specific Task ◽

Spherical Design ◽

Single Degree Of Freedom ◽

End Effector ◽

Single Degree ◽

Folding Pattern ◽

Position Synthesis ◽

Space Requirements

This paper presents a finite position synthesis (f.p.s.) procedure of a spatial single-degree-of-freedom linkage that we call origami-evolved, spherically constrained spatial revolute–revolute (RR) chain here. This terminology is chosen because the linkage may be found from the mechanism equivalent of an origami folding pattern, namely, known as the Miura-ori folding. As shown in an earlier work, the linkage under consideration has naturally given slim shape and essentially represents two specifically coupled spherical four-bar linkages, whose links may be identified with spherical and spatial RR chains. This provides a way to apply the well-developed f.p.s. theory of these linkage building blocks in order to design the origami-evolved linkage for a specific task. The result is a spherically constrained spatial RR chain, whose end effector may reach three finitely separated task positions. Due to an underspecified spherical design problem, the procedure provides several free design parameters. These can be varied in order to match further given requirements of the task. This is shown in a design example with particularly challenging space requirements, which can be fulfilled due to the naturally given slim shape.

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Kinematic and Kinetostatic Synthesis of Planar Coupled Serial Chain Mechanisms

Journal of Mechanical Design ◽

10.1115/1.1464563 ◽

2002 ◽

Vol 124 (2) ◽

pp. 301-312 ◽

Cited By ~ 27

Author(s):

Venkat Krovi ◽

G. K. Ananthasuresh ◽

Vijay Kumar

Keyword(s):

Degree Of Freedom ◽

Dimensional Synthesis ◽

Single Degree Of Freedom ◽

End Effector ◽

Solution Approach ◽

Single Degree ◽

Design Specifications ◽

Serial Chain ◽

Gear Trains ◽

External Loads

Single Degree-of-freedom Coupled Serial Chain (SDCSC) mechanisms form a novel class of modular and compact mechanisms with a single degree-of-freedom, suitable for a number of manipulation tasks. Such SDCSC mechanisms take advantage of the hardware constraints between the articulations of a serial-chain linkage, created using gear-trains or belt/pulley drives, to guide the end-effector motions and forces. In this paper, we examine the dimensional synthesis of such SDCSC mechanisms to perform desired planar manipulation tasks, taking into account task specifications on both end-effector motions and forces. Our solution approach combines precision point synthesis with optimization to realize optimal mechanisms, which satisfy the design specifications exactly at the selected precision points and approximate them in the least-squares sense elsewhere along a specified trajectory. The designed mechanisms can guide a rigid body through several positions while supporting arbitrarily specified external loads. Furthermore, torsional springs are added at the joints to reduce the overall actuation requirements and to enhance the task performance. Examples from the kinematic and the kinetostatic synthesis of planar SDCSC mechanisms are presented to highlight the benefits.

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Finite Element Simulation and Assessment of Single-Degree-of-Freedom Prediction Methodology for Insulated Concrete Sandwich Panels Subjected to Blast Loads

10.15554/pci.rr.misc-003 ◽

2011 ◽

Author(s):

Charles Michael Newberry

Keyword(s):

Finite Element ◽

Finite Element Simulation ◽

Sandwich Panels ◽

Degree Of Freedom ◽

Blast Loads ◽

Single Degree Of Freedom ◽

Single Degree ◽

Element Simulation

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Non-Linear Vibration Problems Treated by the Averaging Method of W. Ritz. Part 2. Single Degree of Freedom Systems Single Term Approximations

10.21236/ada800270 ◽

1951 ◽

Cited By ~ 3

Author(s):

Karl Klotter

Keyword(s):

Averaging Method ◽

Degree Of Freedom ◽

Linear Vibration ◽

Single Degree Of Freedom ◽

Single Degree ◽

Single Term ◽

Non Linear ◽

Vibration Problems

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A cross-species neural integration of gravity for motor optimization

Science Advances ◽

10.1126/sciadv.abf7800 ◽

2021 ◽

Vol 7 (15) ◽

pp. eabf7800

Author(s):

Jeremie Gaveau ◽

Sidney Grospretre ◽

Bastien Berret ◽

Dora E. Angelaki ◽

Charalambos Papaxanthis

Keyword(s):

Optimization Strategy ◽

Motor Patterns ◽

Activation Patterns ◽

Single Degree Of Freedom ◽

Single Degree ◽

Neural Integration ◽

Gravity Effects ◽

Neural Signature ◽

Experimental Findings ◽

Muscular Activation

Recent kinematic results, combined with model simulations, have provided support for the hypothesis that the human brain shapes motor patterns that use gravity effects to minimize muscle effort. Because many different muscular activation patterns can give rise to the same trajectory, here, we specifically investigate gravity-related movement properties by analyzing muscular activation patterns during single-degree-of-freedom arm movements in various directions. Using a well-known decomposition method of tonic and phasic electromyographic activities, we demonstrate that phasic electromyograms (EMGs) present systematic negative phases. This negativity reveals the optimal motor plan’s neural signature, where the motor system harvests the mechanical effects of gravity to accelerate downward and decelerate upward movements, thereby saving muscle effort. We compare experimental findings in humans to monkeys, generalizing the Effort-optimization strategy across species.

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