How to push a block along a wall

Some robot tasks require manipulation of objects that may be touching other fixed objects. The effects of friction and kinematic constraint must be anticipated, and may even be exploited to accomplish the task. An example task, a dynamic analysis, and appropriate effector motions are presented. The goal is to move a rectangular block along a wall, so that one side of the block maintains contact with the wall. Two solutions that push the block along the wall are discussed

Robust Execution of Contact-Rich Motion Plans by Hybrid Force-Velocity Control

In hybrid force-velocity control, the robot can use velocity control in some directions to follow a trajectory, while performing force control in other directions to maintain contacts with the environment regardless of positional errors. We call this way of executing a trajectory hybrid servoing. We propose an algorithm to compute hybrid force-velocity control actions for hybrid servoing. We quantify the robustness of a control action and make trade-offs between different requirements by formulating the control synthesis as optimization problems. Our method can efficiently compute the dimensions, directions and magnitudes of force and velocity controls. We demonstrated by experiments the effectiveness of our method in several contact-rich manipulation tasks. Link to the video: https://youtu.be/KtSNmvwOenM.Comment: Proceedings of IEEE International Conference on Robotics and Automation (ICRA2019

Creating and Strengthening the Therapeutic System for Treatment Setting Serving Deaf Children

Treating deaf children with severe emotional and behavior problems, especially in residential and alternative school treatment settings, is a demanding undertaking. Finding and retaining skilled mental health paraprofessionals are continual challenges faced by mental health service providers. These challenges are even greater when the children served are deaf, and when staff members are expected to be multilingual, be knowledgeable about deaf culture, and be able to treat children with a multitude of severe mental health disturbances. Staff members face the dilemma of both raising and treating children in the same setting with limited resources. Limited funding and limited service models encourage the practice of hiring staff members with minimal skill requirements, at low-end payrates, and with little support or training. This article (a) identifies the issues which threaten the delivery of quality treatment for deaf children with severe emotional and behavioral problems; (b) describes the process that changes well-meaning staff into casualties of their work, and (c) makes recommendations for mental health service administrators, supervisors and agencies to help create and strengthen their therapeutic system

A Convex Polynomial Force-Motion Model for Planar Sliding: Identification and Application

We propose a polynomial force-motion model for planar sliding. The set of generalized friction loads is the 1-sublevel set of a polynomial whose gradient directions correspond to generalized velocities. Additionally, the polynomial is confined to be convex even-degree homogeneous in order to obey the maximum work inequality, symmetry, shape invariance in scale, and fast invertibility. We present a simple and statistically-efficient model identification procedure using a sum-of-squares convex relaxation. Simulation and robotic experiments validate the accuracy and efficiency of our approach. We also show practical applications of our model including stable pushing of objects and free sliding dynamic simulations.Comment: 2016 IEEE International Conference on Robotics and Automation (ICRA

Panel #2: The Maine-Missouri Crisis and the Politics of Slavery

A panel that included three presentations: African Americans and the Political Consequences of Maine Statehood, Mary T. Freeman Doughface Pioneer: John Holmes of Maine, 1773-1843, Matthew Mason Fire Bell in the Night: The Establishment of a Slave Society in Jefferson\u27s Purchase, Diane Mutti Burk