Glenn Saunders

Camera-Based Ballot Counter

Portable ballot counters using camera technology and manual paper feed are potentially more reliable and less expensive than scanner-based systems. We show that the spatial sampling rate, geometric linearity, point-spread function, and photometric transfer function of off-the shelf consumer cameras are acceptable for ballot imaging. However, scanner illumination is much more uniform than can be economically accomplished for variable size ballots. Therefore flat-field compensation must be designed into the image processing software. We illustrate the mechanical design of a prototype camera-based ballot reader based on our comparative observations.

Design of a Large Scale Vertical Stabilizer Wind Tunnel Model for Active Flow Control Research

The design, fabrication and installation of an approximately 1/6 scale model of an aircraft vertical stabilizer for research in Active Flow Control (AFC) is discussed. Highlighted are the unique design requirements of wind tunnel models, the specialized fabrication techniques employed to create them and the required close collaboration between industry, government and three academic institutions. The design of the model involves often competing constraints imposed by structural, instrumentation, aerodynamic, manufacturability and research-agenda considerations as well as cost and schedule. Instrumentation requires hundreds of pressure ports and six-axis force/torque sensing. Aerodynamic considerations necessitate high manufacturing precision, highly-skilled fabrication techniques and careful observance of model geometry throughout the design and fabrication processes. A scale model of a vertical stabilizer for AFC research was successfully designed, fabricated and deployed. The collaboratively designed model satisfies the structural, aerodynamic and research design constraints, and furthers the state of the art in Active Flow Control research.Copyright

Model-based design automation and process automation in titanium sheet metal manufacturing

Two modeling techniques are employed to study two automation goals for a manufacturing process; automation of the design of custom-engineered dies and automation of the manufacturing process that uses them. In both cases the objective is to improve energy efficiency and throughput of a manufacturing process known as “Hotsizing”. Finite Element Modeling (FEM) is used to study the surface temperature distribution of dies used to form titanium blanks into finished parts. First-order analytical modeling is used to study the heat transfer mechanisms at work in heating the blanks and moving them through air from a preheat oven to a forming press. FEM results show that contrary to our hypotheses, die surface temperatures are quite uniform and model-based design of the dies to guide sensor placement so as to minimize surface temperature variation is not justifiable. Analytical modeling reveals unforeseen, potentially substantial energy and throughput improvement and justifiable manufacturing process automation.

Auxiliary Axis for Rensselaer’s Geotechnical Centrifuge Center In-Flight Robot: Design Considerations

Rensselaer’s Geotechnical Centrifuge Center is a resource for conducting research into the behavior of soils, earthen structures and other materials under high g-force conditions. The 3m radius centrifuge can accelerate a roughly 1m × 1m × 1m payload up to as much as 200 g’s. Under such loading, properly prepared soil samples accurately simulate deep soil conditions at 1 g. The system also includes an In-flight Robot that provides the capability to perform experiments while the centrifuge is in operations, as well as a 2–D shaker and associated 2–D Laminar Box that permit earthquake simulations while in flight. However prior to the implementation of the Auxiliary Axis, pilings were limited to a maximum usable length of approximately 15cm. The objective of Auxiliary Axis is to provide the capability to handle long pilings (up to 35cm) in situations where both the 2–D Shaker and 2–D Laminar Box are used. The Aux Axis is attached to the exterior of the in-flight robot when needed, and removed when not. The Aux Axis is designed to perform in a 50 g’s environment which holds some unique engineering concerns. It is designed so that installation and removal is as simple as possible, and can typically be completed in about 30 minutes. The Aux Axis is powered by the existing robot Z axis motor and belt drive system. Consequently, both the Z axis and the Aux Axis move simultaneously when the Aux Axis is installed. The Aux Axis is geared approximately 8.42 times higher than the Z axis so that it moves much further than the Z axis during operation. This permits the pilings; which are attached to the Aux Axis, to be fully inserted into the soil sample before the Z axis has moved far enough to interfere with the top of the 2–D Laminar Box.Copyright