Generating multiple new designs from a sketch

AbstractWe describe a program called SketchIT that transforms a single sketch of a mechanical device into multiple families of new designs. It represents each of these families with a “BEP-Model”, a parametric model augmented with constraints that ensure the device produces the desired behavior. The program is based on qualitative configuration space (qc-space), a novel representation that captures mechanical behavior while abstracting away its implementation. The program employs a paradigm of abstraction and resynthesis: it abstracts the initial sketch into qc-space, then uses a library of primitive mechanical interactions to map from qc-space to new implementations

SketchIT: A Sketch Interpretation Tool for Conceptual Mechanical Design

We describe a program called SketchIT capable of producing multiple families of designs from a single sketch. The program is given a rough sketch (drawn using line segments for part faces and icons for springs and kinematic joints) and a description of the desired behavior. The sketch is "rough" in the sense that taken literally, it may not work. From this single, perhaps flawed sketch and the behavior description, the program produces an entire family of working designs. The program also produces design variants, each of which is itself a family of designs. SketchIT represents each family of designs with a "behavior ensuring parametric model" (BEP-Model), a parametric model augmented with a set of constraints that ensure the geometry provides the desired behavior. The construction of the BEP-Model from the sketch and behavior description is the primary task and source of difficulty in this undertaking. SketchIT begins by abstracting the sketch to produce a qualitative configuration space (qc-space) which it then uses as its primary representation of behavior. SketchIT modifies this initial qc-space until qualitative simulation verifies that it produces the desired behavior. SketchIT's task is then to find geometries that implement this qc-space. It does this using a library of qc-space fragments. Each fragment is a piece of parametric geometry with a set of constraints that ensure the geometry implements a specific kind of boundary (qcs-curve) in qc-space. SketchIT assembles the fragments to produce the BEP-Model. SketchIT produces design variants by mapping the qc-space to multiple implementations, and by transforming rotating parts to translating parts and vice versa

LearnIT: An Instance-Based Approach Learning and Reusing Design Strategies,”

We describe LearnIT, a compute

A SKETCH-BASED INTERFACE FOR THE DESIGN AND ANALYSIS OF SIMPLE VIBRATORY MECHANICAL SYSTEMS

ABSTRACT We describe a sketch-based interface designed to provide engineers with a computer environment similar to pen and paper. With our interface, users can construct functional engineering models simply by drawing sketches on a computer screen. Unlike paper sketches, however, our interface allows users to interact with their sketches in real time to modify existing objects and add new ones. To demonstrate the utility of our system, we have developed a sketch-based interface for designing and analyzing simple vibratory mechanical systems. The technical contributions of our work include: (1) a sketch parsing method for automatically locating the distinct graphical symbols in a sketch, (2) a general-purpose, trainable symbol recognizer, and (3) special purpose prerecognizers that consider shape information and make use of drawing conventions. Introduction Our work aims to create natural user interfaces that allow people to operate software using the same sorts of sketches that they would ordinarily use for problem solving and communicating with others. In many disciplines, sketches have great utility as a problem solving tool, as they provide a suitable medium for recording elusive thoughts, visualizing and testing emerging ideas, and for compactly and efficiently representing various types of information such as spatial, temporal and causal relationships. In the realm of engineering and architecture, sketches greatly facilitate conceptual design activities by freeing the designer from worrying about intricate details such as precise size

A 20-year experience with urgent percutaneous cardiopulmonary bypass for salvage of potential survivors of refractory cardiovascular collapse

In-hospital cardiac arrest or refractory shock carries a high mortality despite the use of advanced resuscitative measures. We have implemented an in-hospital, nurse-based, continuously available, percutaneous, venoarterial cardiopulmonary bypass system, also known as extracorporeal life support (ECLS), as an adjunct to resuscitation when initial measures are ineffective.In 1986, a system for the rapid initiation of ECLS, was created in which trained critical care nurses primed an ECLS circuit and in-house physicians percutaneously placed required cannulas. From a prospective registry, we assessed long-term survival (LTS) (≥30 days, cardiopulmonary support weaned), short-term survival (<30 days, CPS weaned), or death on CPS.One hundred fifty patients (age, 57 ± 17 years) were urgently started on CPS for cardiac arrest (n = 127; witnessed, n = 124; unwitnessed, n = 3) and refractory shock (n = 23). Sixty-nine patients were weaned from CPS, and 81 could not be weaned. Overall, 39 (26.0%) patients achieved LTS with a subsequent Kaplan–Meier median survival of 9.5 years. Duration of CPS was 32 ± 38 hours for LTS and 21 ± 38 hours for non-LTS. LTS occurred in 29 (23.4%) of 124 patients started on CPS for witnessed cardiac arrest and 11 (47.8%) of 23 for refractory shock ( < .05). Among patients with CPS initiated in the cardiac catheterization laboratory, LTS was seen in 24 (50.0%) of 48 versus 15 (14.7%) of 102 in patients with CPS initiated in other locations ( < .001). Cardiopulmonary resuscitation times greater than or equal to 30 minutes were associated with lower LTS ( < .05). The most common cause of death during CPS was refractory cardiac dysfunction (39.5%), and the most common cause associated with short-term survival was neurologic/pulmonary dysfunction (53.6%). Seven patients were bridged to a left ventricular assist device, and 1 subsequently underwent heart transplantation. Multivariate analysis revealed only cardiac catheterization laboratory site of initiation as a significant independent predictor of LTS ( < .01). When dividing the 20-year experience in tertiles, recent recipients have had more common prearrest insertion. Rates of long-term survival have not changed.Of patients started on CPS, 46% were weaned, and 26.0% were long-time survivors. Rapid initiation of CPS permits LTS for some inpatients with cardiovascular collapse when initial advanced resuscitation fails. Strategies to improve end-organ function associated with use of CPS should lead to greater LTS. This practical application of inexpensive available technology should be more widely used

Bittersweet: Newly Diagnosed Type 1 Diabetes Characteristics & Complexities Observed During the Early Phases of the COVID-19 Pandemic

Type I diabetes management is complex and multifaceted. The COVID-19 pandemic has added to the complexity of Type 1 diabetes (T1D) diagnosis and management. This article reviews the literature surrounding patient characteristics of those with a new diagnosis of Type 1 diabetes, including those with Diabetic Ketoacidosis (DKA), during the early phase of the pandemic

SketchIT: a sketch interpretation tool for conceptual mechanism design

We describe a program called SketchIT capable of producing multiple families of designs from asinglesketch. The program is given a rough sketch (drawn using line segments for part faces and icons for springs and kinematic joints) and a description of the desired behavior. The sketch is “rough” in the sense that taken literally, it may not work. From this single, perhaps flawed sketch and the behavior description, the program produces an entire family of working designs. The program also produces design variants, each of which is itself a family of designs. SketchIT represents each family of designs with a “behavior ensuring parametric model ” (BEP-Model), a parametric model augmented with a set of constraints that ensure the geometry provides the desired behavior. The construction of the BEP-Model from the sketch and behavior description is the primary task and source of difficulty in this undertaking. SketchIT begins by abstracting the sketch to produce a qualitative configuration space (qcspace) which it then uses as its primary representation of behavior. SketchIT modifies this initia