Towards Interactive, Incremental Programming of ROS Nodes

Writing software for controlling robots is a complex task, usually demanding command of many programming languages and requiring significant experimentation. We believe that a bottom-up development process that complements traditional component- and MDSD-based approaches can facilitate experimentation. We propose the use of an internal DSL providing both a tool to interactively create ROS nodes and a behaviour-replacement mechanism to interactively reshape existing ROS nodes by wrapping the external interfaces (the publish/subscribe topics), dynamically controlled using the Python command line interface.Comment: Presented at DSLRob 2014 (arXiv:cs/1411.7148

Institutional Causes, Macroeconomic Symptoms: Volatility, Crises and Growth

Countries that have pursued distortionary macroeconomic policies, including high inflation, large budget deficits and misaligned exchange rates, appear to have suffered more macroeconomic volatility and also grown more slowly during the postwar period. Does this reflect the causal effect of these macroeconomic policies on economic outcomes? One reason to suspect that the answer may be no is that countries pursuing poor macroeconomic policies also have weak 'institutions,' including political institutions that do not constrain politicians and political elites, ineffective enforcement of property rights for investors, widespread corruption, and a high degree of political instability. This paper documents that countries that inherited more 'extractive' instit utions from their colonial past were more likely to experience high volatility a nd economic crises during the postwar period. More specifically, societies where European colonists faced high mortality rates more than 100 years ago are much more volatile and prone to crises. Based on our previous work, we interpret this relationship as due to the causal effect of institutions on economic outcomes: Europeans did not settle and were more likely to set up extractive institutions in areas where they faced high mortality. Once we control for the effect of institutions, macroeconomic policies appear to have only a minor impact on volatility and crises. This suggests that distortionary macroeconomic policies are more likely to be symptoms of underlying institutional problems rather than the main causes of economic volatility, and also that the effects of institutional differences on volatility do not appear to be primarily mediated by any of the standard macroeconomic variables. Instead, it appears that weak institutions cause volatility through a number of microeconomic, as well as macroeconomic, channels.

Dense Building Instrumentation Application for City-Wide Structural Health Monitoring

The Community Seismic Network (CSN) has partnered with the NASA Jet Propulsion Laboratory (JPL) to initiate a campus-wide structural monitoring program of all buildings on the premises. The JPL campus serves as a proxy for a densely instrumented urban city with localized vibration measurements collected throughout the free-field and built environment. Instrumenting the entire campus provides dense measurements in a horizontal geospatial sense for soil response; in addition five buildings have been instrumented on every floor of the structure. Each building has a unique structural system as well as varied amounts of structural information via structural drawings, making several levels of assessment and evaluation possible. Computational studies with focus on damage detection applied to the campus structural network are demonstrated for a collection of buildings. For campus-wide real-time and post-event evaluation, ground and building response products using CSN data are illustrating the usefulness of higher spatial resolution compared to what was previously typical with sparser instrumentation

Augmenting the field experience: a student-led comparison of techniques and technologies

In this study we report on our experiences of creating and running a student fieldtrip exercise which allowed students to compare a range of approaches to the design of technologies for augmenting landscape scenes. The main study site is around Keswick in the English Lake District, Cumbria, UK, an attractive upland environment popular with tourists and walkers. The aim of the exercise for the students was to assess the effectiveness of various forms of geographic information in augmenting real landscape scenes, as mediated through a range of techniques and technologies. These techniques were: computer-generated acetate overlays showing annotated wireframe views from certain key points; a custom-designed application running on a PDA; a mediascape running on the mScape software on a GPS-enabled mobile phone; Google Earth on a tablet PC; and a head-mounted in-field Virtual Reality system. Each group of students had all five techniques available to them, and were tasked with comparing them in the context of creating a visitor guide to the area centred on the field centre. Here we summarise their findings and reflect upon some of the broader research questions emerging from the project