Preshaping command inputs to reduce telerobotic system oscillations

The results of using a new technique for shaping inputs to a model of the space shuttle Remote Manipulator System (RMS) are presented. The shapes inputs move the system to the same location that was originally commanded, however, the oscillations of the machine are considerably reduced. An overview of the new shaping method is presented. A description of RMS model is provided. The problem of slow joint servo rates on the RMS is accommodated with an extension of the shaping method. The results and sample data are also presented for both joint and three-dimensional cartesian motions. The results demonstrate that the new shaping method performs well on large, telerobotic systems which exhibit significant structural vibration. The new method is shown to also result in considerable energy savings during operations of the RMS manipulator

Method and apparatus for creating time-optimal commands for linear systems

A system for and method of determining an input command profile for substantially any dynamic system that can be modeled as a linear system, the input command profile for transitioning an output of the dynamic system from one state to another state. The present invention involves identifying characteristics of the dynamic system, selecting a command profile which defines an input to the dynamic system based on the identified characteristics, wherein the command profile comprises one or more pulses which rise and fall at switch times, imposing a plurality of constraints on the dynamic system, at least one of the constraints being defined in terms of the switch times, and determining the switch times for the input to the dynamic system based on the command profile and the plurality of constraints. The characteristics may be related to poles and zeros of the dynamic system, and the plurality of constraints may include a dynamics cancellation constraint which specifies that the input moves the dynamic system from a first state to a second state such that the dynamic system remains substantially at the second state

A Simplified Method for Deriving Equations of Motion For Continuous Systems with Flexible Members

A method is proposed for deriving dynamical equations for systems with both rigid and flexible components. During the derivation, each flexible component of the system is represented by a "surrogate element" which captures the response characteristics of that component and is easy to mathematically manipulate. The derivation proceeds essentially as if each surrogate element were a rigid body. Application of an extended form of Lagrange's equation yields a set of simultaneous differential equations which can then be transformed to be the exact, partial differential equations for the original flexible system. This method's use facilitates equation generation either by an analyst or through application of software-based symbolic manipulation

Engineering Methods for Decision-Making

Presentation on engineering methods for decision-makin

Assessing Information Waste in Lean Product Development

Lean Product Development seeks to enhance the efficiency of product development projects by reducing and eliminating non-value-adding activities or waste, which can exist on every process level. The value stream through product development processes is a flow of information, and hence waste exists in interpersonal communication. The study elaborates the hypothesis that most information transfers do not add value to the product. It was further theorized that different means of communication are better suited for different kinds of information, at least from the lean point of view. In order to understand the occurrence and ramifications of waste in product development information flows, the information transferred between team members was analyzed in two student product development projects. With the help of a paper-based value stream map, frequencies of waste drivers in information, the share of waste in information transfers, the interdependencies of waste and means of communication, as well as timeliness of information transfers were analyzed. The study’s results show that waste is omnipresent in product development information transfers, as only twelve percent of all information transfers contribute value to the product, and nearly half of the information transfers could have been omitted without a decrease in product value. Assuming that preparing, sending, receiving and retrieving information accounts for most of the time spent in product development processes, an enormous theoretical potential for efficiency enhancements could thus be identified

Using Design of Experiments (DOE) for Decision Analysis

We take an engineering design approach to a problem of the artificial - corporate decision-analysis under uncertainty. We use Design of Experiments (DOE) to understand the behaviour of systems within which decisions are made and to estimate the consequences of alternative decisions. The experiments are a systematically constructed class of gedanken (thought) experiments comparable to “what if” studies, but organized to span the entire space of controllable and uncontrollable options. We therefore develop a debiasing protocol to forecast and elicit data. We consider the composite organization, their knowledge, data bases, formal and informal procedures as a measurement system. We use Gage theory from Measurement System Analysis (MSA) to analyze the quality of the data, the measurement system, and its results. We report on an in situ company experiment. Results support the statistical validity and managerial efficacy of our method. Method-evaluation criteria also indicate the validity of our method. Surprisingly, the experiments result in representations of near-decomposable systems. This suggests that executives scale corporate problems for analyses and decision-making. This work introduces DOE and MSA to the management sciences and shows how it can be effective to executive decision making

Ex Ante Evaluation and Improvement of Forecasts

The dominant approach reported in the literature is to evaluate forecasts after the fact. We take a different approach, we present a way to evaluate and Improve forecasts before the fact. We reconceptualize forecasts as thought experiments grounded on mental models. We show the results of our process which debiases and reduces the asymmetry of forecasters’ mental models. We also reconceptualize forecasting as measurements with errors. And to analyze and improve the entire forecasting process as a system, we use the methods of Design of Experiments (DOE) and Gage R&R from Measurement System Analysis (MSA). We show the results of our analyses using two new metrics, repeatability and reproducibility and discuss new opportunities for research

Enabling Factors in Successful Product Development

The research literature and industry best-practices report a vast number of enabling factors that contribute to successful product development (PD). Collectively this body of work also establishes the causal linkages between these enabling factors and overall success in PD. But what specific factors will produce what specific outcomes are vague and ambiguous. To address this apparent void, we find distinct sets of PD enabling factors that are statistically accurate predictors of the specific project outcomes of profit, market share, customer satisfaction, organizational effectiveness, and product quality. We are also motivated to help organizations improve their PD. To that end, we develop a diagnostic tool using the factors that predict our five PD outcomes. The tool is used to pinpoint weaknesses and focus improvements to achieve specific desired outcomes. Results of in situ testing of the tool are reported in this article. The guiding principles of this work are specificity and actionability: specific enabling factors that can produce specific results, and an actionable diagnostic-tool that practitioners can use to improve the practice and results of their PD projects

Inhibiting multiple mode vibration in controlled flexible systems

Viewgraphs on inhibiting multiple mode vibration in controlled flexible systems are presented. Topics covered include: input pre-shaping background; developing multiple-mode shapers; Middeck Active Control Experiment (MACE) test article; and tests and results

Implementation of input command shaping to reduce vibration in flexible space structures

Viewgraphs on implementation of input command shaping to reduce vibration in flexible space structures are presented. Goals of the research are to explore theory of input command shaping to find an efficient algorithm for flexible space structures; to characterize Middeck Active Control Experiment (MACE) test article; and to implement input shaper on the MACE structure and interpret results. Background on input shaping, simulation results, experimental results, and future work are included