Many factors such as size, power, and weight constrain the design of modular snake robots. Meeting these constraints requires implementing a complex mechanical electrical architecture. Here we present our solution, which involves construction sixteen aluminum modules creation Super Servo, modified hobby servo. To create have replaced electronics in servo, adding components sensors to monitor current temperature, communications bus, programmable microcontroller. Any robust solution must also...

Abstract While there are many issues to be raised in using lethal autonomous robotic weapons (beyond those of remotely operated drones), we argue that the most important question is: should decision take a human life relinquished machine? This is often overlooked favor technical questions sensor capability, operational chain command, or legal sovereign borders. We further answer must 'no' and offer several reasons for banning robots. (1) Such robot treats as an object, instead person with...

Rigid bodies, plastic impact, persistent contact, Coulomb friction, and massless limbs are ubiquitous simplifications introduced to reduce the complexity of mechanics models despite obvious physical inaccuracies that each incurs individually. In concert, it is well known interaction such idealized approximations can lead conflicting even paradoxical results. As robotics modeling moves from consideration isolated behaviors analysis tasks requiring their composition, a mathematically tractable...

Model predictive control (MPC) is a popular strategy for controlling robots but difficult systems with contact due to the complex nature of hybrid dynamics. To implement MPC contact, dynamic models are often simplified or sequences fixed in time order plan trajectories efficiently. In this work, we propose iterative linear quadratic regulator (iLQR) (HiLQR), which extends iLQR class piecewisesmooth dynamical state jumps. This accomplished by, first, allowing changing modes forward pass,...

For mobile robots, the essential units of actuation, computation, and sensing must be designed to fit within body robot. Additional capabilities will largely depend upon a given activity, should easily reconfigurable maximize diversity applications experiments. To address this issue, we introduce modular architecture originally developed tested in design implementation X-RHex hexapod that allows robot operate as laboratory on legs. In present paper specification, very earliest operational...

As dynamic robot behaviors become more capable and well understood, the need arises for a wide variety of equally systematically applicable transitions between them. We use hybrid systems framework to characterize planar "legged" rigid body from rest on level ground fully aerial state. The various contact conditions fit together form topologically regular structure, "ground reaction complex". body's actuated dynamics excite multifarious cells this complex, whose adjacency relations index...

This paper develops a comparative framework for the design of actuated inertial appendages planar, aerial reorientation. We define Inertial Reorientation template, simplest model this behavior, and leverage its linear dynamics to reveal constraints linking task with body designs capable completing it. As practicable appendage lead morphology that is generally more complex, we advance notion "anchoring" whereby judicious choice physical in concert an appropriate control policy yields system...

<h3>Importance</h3> COVID-19 vaccine uptake among urban populations remains low. <h3>Objective</h3> To evaluate whether text messaging with outbound or inbound scheduling and behaviorally informed content might increase uptake. <h3>Design, Setting, Participants</h3> This randomized clinical trial a factorial design was conducted from April 29 to July 6, 2021, in an academic health system. The comprised 16 045 patients at least 18 years of age Philadelphia, Pennsylvania, 1 primary care visit...

We examine consequences of the non-Boltzmann nature probability distributions for one-particle kinetic energy, momentum, and velocity finite systems classical hard spheres with constant total energy nonidentical masses. By comparing two cases, reflecting walls (NVE or microcanonical ensemble) periodic boundaries (NVEPG molecular dynamics ensemble), we describe three center-of-mass constraint in boundary conditions: equipartition theorem no longer holds unequal masses, ratio average relative...

This paper documents near-autonomous negotiation of synthetic and natural climbing terrain by a rugged legged robot, achieved through sequential composition appropriate perceptually triggered locomotion primitives. The first, simple achieves autonomous uphill climbs in unstructured outdoor while avoiding surrounding obstacles such as trees bushes. second, slightly more complex stairwell variety different buildings. In both cases, the intrinsic motor competence platform requires only small...

This paper introduces self-manipulation as a new formal design methodology for legged robots with varying ground interactions. The term denotes set of modeling choices that permit uniform and body-centric representation the equations motion—essentially guide to selection configuration coordinate frames. We present hybrid system kinematics, dynamics, transitions in form consistently structured simplifies unites account these, otherwise bewilderingly diverse differential algebraic equations....

How can a robot design sequence of grasping actions that will succeed despite the presence bounded state uncertainty and an inherently stochastic system? In this letter, we propose probabilistic algorithm generates sequential to iteratively reduce until object pose is uniquely known (subject symmetry). The plans assume encoder feedback gives geometric partition post-grasp configuration space based on contact conditions. An offline planning tree generated by interleaving computationally...

In this letter, we propose a method to improve the accuracy of trajectory optimization for dynamic robots with intermittent contact by using orthogonal collocation. Until recently, most methods systems contacts employ mode-scheduling, which requires an priori knowledge order and thus cannot produce complex or non-intuitive behaviors. Contact-implicit offer solution allowing make break as needed, but far have suffered from poor accuracy. Here, combine direct collocation higher polynomials...

We present TartanDrive, a large scale dataset for learning dynamics models off-road driving. collected of roughly 200,000 driving interactions on modified Yamaha Viking ATV with seven unique sensing modalities in diverse terrains. To the authors' knowledge, this is largest real-world multi-modal dataset, both terms number and modalities. also benchmark several state-of-the-art methods model-based reinforcement from high-dimensional observations dataset. find that extending these to...

We propose a number of "divergence metrics" to quantify the robustness trajectory state uncertainty for under-actuated or under-sensed systems. These metrics are inspired by contraction analysis and we demonstrate their use guide randomized planners toward more convergent trajectories through three extensions kinodynamic RRT. The first strictly thresholds action selection based on these metrics, forcing planner find solution that lies within region over which all initial conditions converge...

Many agile legged animals employ lightweight, furry tails to regulate orientation during running, leaping, and turning. Most robots attempting the same tasks either lack a tail or one with high inertia, which can induce impractical payload energy costs. Inspired by nature's solution this tradeoff, we explore use of aerodynamic drag in reorientation tasks. In article, present model from derive metric that allows for direct comparison between inertial tails. Motivated model, construct maximize...

The Direct Drive Hand (DDHand) project is exploring an alternative design philosophy for grippers.The conventional approach to prioritize clamping force, leading high gear ratios, slow motion, and poor transmission of force/motion signals.Instead, the DDHand prioritizes transparency: we view gripper as a signal channel, seek high-bandwidth, highfidelity force motion signals in both directions.The resulting has no gears springs, occupying new quadrant servo space.This paper presents direct...

Many state estimation and control algorithms require knowledge of how probability distributions propagate through dynamical systems. However, despite hybrid systems becoming increasingly important in many fields, there has been little work on utilizing the map transitions. Here, we make use a propagation law that employs saltation matrix (a first-order update to sensitivity equation) create Salted Kalman Filter (SKF), natural extension Extended Away from events, SKF is standard filter. When...

Terrain identification is a key enabling ability for generating terrain adaptive behaviors that assist both robot planning and motor control. This paper considers running legged robots from the RHex family) which military plans to use in field troops reconnaissance tasks. Important include selection of gaits) modulation leg stiffness) alteration steering control laws minimize slippage) maximize speed and/or reduce energy consumption. These can be enabled by methodology combines...

Abstract This paper reports on an autonomous ascent by a legged robotic platform in outdoor forested terrain. Two controllers govern the integration of online inertial measurement unit and light detection ranging sensor signals into commands for climbing means abstracted ( unicycle ) representation support different performance goals: kinematic version endurance dynamic speed. These control laws, backed suite formal correctness guarantees, encourage stripped‐down sensory supporting...