Beyond records and representations: inbetween writing in educational ethnography

Ethnographers are particularly interested in writing. They have paid particular attention to the practices of making field notes and to the ways in which their public texts represent those that they have encountered and studied. To date there has been less attention paid to the kinds of writing that used to make sense of experiences in the field. We call this inbetween writing. By examining our own processes of inbetween writing, and drawing on the work of James Clifford, we have produced a nine-part heuristic of inbetween writing. We argue that the heuristic could be used in research methods education to highlight the importance of writing to ethnographic sense-making and knowledge production

A Comparison of Inverse Simulation-Based Fault Detection in a Simple Robotic Rover with a Traditional Model-Based Method

Robotic rovers which are designed to work in extra-terrestrial environments present a unique challenge in terms of the reliability and availability of systems throughout the mission. Should some fault occur, with the nearest human potentially millions of kilometres away, detection and identification of the fault must be performed solely by the robot and its subsystems. Faults in the system sensors are relatively straightforward to detect, through the residuals produced by comparison of the system output with that of a simple model. However, faults in the input, that is, the actuators of the system, are harder to detect. A step change in the input signal, caused potentially by the loss of an actuator, can propagate through the system, resulting in complex residuals in multiple outputs. These residuals can be difficult to isolate or distinguish from residuals caused by environmental disturbances. While a more complex fault detection method or additional sensors could be used to solve these issues, an alternative is presented here. Using inverse simulation (InvSim), the inputs and outputs of the mathematical model of the rover system are reversed. Thus, for a desired trajectory, the corresponding actuator inputs are obtained. A step fault near the input then manifests itself as a step change in the residual between the system inputs and the input trajectory obtained through inverse simulation. This approach avoids the need for additional hardware on a mass- and power-critical system such as the rover. The InvSim fault detection method is applied to a simple four-wheeled rover in simulation. Additive system faults and an external disturbance force and are applied to the vehicle in turn, such that the dynamic response and sensor output of the rover are impacted. Basic model-based fault detection is then employed to provide output residuals which may be analysed to provide information on the fault/disturbance. InvSim-based fault detection is then employed, similarly providing \textit{input} residuals which provide further information on the fault/disturbance. The input residuals are shown to provide clearer information on the location and magnitude of an input fault than the output residuals. Additionally, they can allow faults to be more clearly discriminated from environmental disturbances

Building Civic Capacity for College Students: Flexible Thinking and Communicating as Puppeteers, Community Partners, and Citizen-Leaders

College students face a complex world filled with pervasive social problems that require strong knowledge bases, critical thinking abilities, and sustained engagement in civic life. This article details key pedagogical practices for our innovative health puppetry program, in which undergraduate honors students use puppets to share information about healthy eating, diabetes prevention, and active lifestyles with children and their families in community settings. We articulate a notion of “flexible thinking” as the ability to take on and perform new roles within the public/civic arena by seeing complex social problems from multiple perspectives and responding with creative solutions and engaged action. We look to the written reflections of our student puppeteers to share, in their own words, multiple ways their thinking and communication changed as they grew as puppeteers, community partners, and citizen-leaders. We also offer insights about promoting flexible thinking through in-depth service-learning

Inverse Simulation as a Tool for Fault Detection and Isolation in Planetary Rovers

With manned expeditions to planetary bodies beyond our own and the Moon currently intractable, the onus falls upon robotic systems to explore and analyse extraterrestrial environments such as Mars. These systems typically take the form of wheeled rovers, designed to navigate the difficult terrain of other worlds. Rovers have been used in this role since Lunokhod 1 landed on the Moon in 1970. While early rovers were remote controlled, communication latency with bodies beyond the Moon and the desire to improve mission effectiveness have resulted in increasing autonomy in planetary rovers. With an increase in autonomy, however, comes an increase in complexity. This can have a negative impact on the reliability of the rover system. With a fault-free system an unlikely prospect and human assistance millions of miles away, the rover must have a robust fault detection, isolation and recovery (FDIR) system. The need for comprehensive FDIR is demonstrated by the recent Chinese lunar rover, Yutu (or “Jade Rabbit”). Yutu was rendered immobile 42 days after landing and remained so for the duration of its operational life: 31 months. While its lifespan far exceeded its expected value, Yutu's inability to move severely impaired its ability to perform its mission. This clearly highlights the need for robust FDIR. A common approach to FDIR is through the generation and analysis of residuals. Output residuals may be obtained by comparing the outputs of the system with predictions of those outputs, obtained from a mathematical model of the system which is supplied with the system inputs. Output residuals allow simple detection and isolation of faults at the output of the system. Faults in earlier stages of the system, however, propagate through the system dynamics and can disperse amongst several of the outputs. This problem is exemplified by faults at the input, which can potentially excite every system state and thus manifest in every output residual. Methods exist for decoupling and analysing output residuals such that input faults may be isolated, however, these methods are complex and require comprehensive development and testing. A conceptually simpler approach is presented in this paper. Inverse simulation (InvSim) is a numerical method by which the inputs of a system are obtained for a desired output. It does so by using a Newton-Raphson algorithm to solve a non-linear model of the system for the input. When supplied with the outputs of a fault-afflicted system, InvSim produces the input required to drive a fault-free system to this output. The fault therefore manifests itself in this generated input signal. The InvSim-generated input may then be compared to the true system input to generate input residuals. Just as a fault at an output manifests itself in the residual for that output alone, a fault at an input similarly manifests itself only in the residual for that input. InvSim may also be used to generate residuals at other locations in the system, by considering distinct subsystems with their own inputs and outputs. This ability is tested comprehensively in this paper. Faults are applied to a simulated rover at a variety of locations within the system structure and residuals generated using both InvSim and conventional forward simulation. Residuals generated using InvSim are shown to facilitate detection and isolation of faults in several locations using simple analyses. By contrast, forward simulation requires the use of complex analytical methods such as structured residuals or adaptive thresholds

Building Civic Capacity for College Students: Flexible Thinking and Communicating as Puppeteers, Community Partners, and Citizen-Leaders

College students face a complex world filled with pervasive social problems that require strong knowledge bases, critical thinking abilities, and sustained engagement in civic life. This article details key pedagogical practices for our innovative health puppetry program, in which undergraduate honors students use puppets to share information about healthy eating, diabetes prevention, and active lifestyles with children and their families in community settings. We articulate a notion of “flexible thinking� as the ability to take on and perform new roles within the public/civic arena by seeing complex social problems from multiple perspectives and responding with creative solutions and engaged action. We look to the written reflections of our student puppeteers to share, in their own words, multiple ways their thinking and communication changed as they grew as puppeteers, community partners, and citizen-leaders. We also offer insights about promoting flexible thinking through in-depth service-learning