The Harvey Mudd College Clinic Program is a nationally recognized industry sponsored academic program centered around a multidisciplinary approach to real world problem solving. The program consists of roughly 40 projects per year sponsored by industry, in the departments of engineering, computer science, mathematics, and physics. Since the inception of the Clinic Program almost 40 years ago, approximately 1000 projects have been sponsored by more than 250 individual sponsors.

The Clinic Program presents opportunities for juniors and seniors to work on practical projects relevant to industry. The problems usually involve components of measurement, design, simulation, and analysis. Solutions arise from team efforts which integrate the broad laboratory and discipline-specific skills that characterize a Harvey Mudd College education.

Students who are enrolled in the Clinic Program work in teams of four or five under the guidance of a student team leader, a faculty advisor, and a liaison from the sponsoring organization. Some projects are jointly run by several departments to promote cross-fertilization between fields, and to encourage application of diverse viewpoints and a variety of techniques.

In addition to putting into practice the theories learned in the classroom, students must deal with the psychology of teamwork, as well as budget and schedule constraints. Students are required to make oral presentations to public audiences and submit final written reports with any specified deliverables to the sponsoring companies.

Companies currently pay a fee of $41,000 to the college to sponsor a project for one academic year. Sponsoring companies oversee the project by assigning a liaison to maintain close contact with the team. The liaison outlines the project requirements, approves the team's proposal for accomplishing the work, and receives weekly progress reports. In most cases the student team visits the sponsoring company for a midyear design review and, in many instances, provides a summary presentation to senior officials at the end of the project. The sponsor retains Intellectual Property rights.

The college selects Clinic projects on the basis of the quality of the educational experience provided, as well as student interest. Evaluation of the Clinic Program is continuous and occurs in the form of student and sponsor reaction, assessment by a panel of industry-based advisors (the “Clinic Advisory Committee”), and oversight by faculty advisors and the Clinic directors.

Clinic Projects

Soot particles are a common byproduct of combustion. These sub-100-nm carbon particles can lodge deep in the lungs, leading to cardiovascular and pulmonary health problems. They also contribute significantly to air pollution and potentially to global warming. Recent work has clarified the absorption and scattering properties of bare carbon particles in sunlight, but impurities in fuel often produce carbon particles coated with significant layers of sulfur and other dielectric compounds. To understand the role carbon aerosols play on global climate, and potentially to build remote optical diagnostics of soot emissions, it is necessary to measure the optical properties of these coated nanoparticles.

The goal of this clinic is to characterize the light absorption and scattering properties of coated soot aerosols. Soot particles will be generated in the lab by partially combusting ethylene and subsequently coated via a particle coating condenser. Their optical properties will be determined using angle-resolved scattering and cavity ringdown techniques. Last year's team built most of the apparatus, including the means to filter the soot from the exhaust air so it can be exhausted into the room. This year's team is refining the setup, calibrating both ringdown and angle-resolved scattering setups, and investigating the impact of oleic-acid coatings.

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Among the central themes of vision research within the United States today, are the efforts to understand the limits of human visual acuity and the changes in vision associated with aging and retinal disease. The Adaptive Optics group at Lawrence Livermore National Laboratory (LLNL), in collaboration with researchers at the UC Davis Medical Center (UCDMC) and the University of Rochester, has applied adaptive optics technology to the study of the human eye to: (1) measure the visual performance of the eye when virtually all the aberrations of the eye are corrected, and (2) obtain high-resolution images of the retina, thereby allowing correlation of retinal structure with visual performance. The research program at UCDMC has focused specifically on the optical and neural factors responsible for the normal aging of the human visual system, and cellular mechanisms of age-related macular degeneration (AMD), the leading cause of blindness in the United States.

The goal of the LLNL clinic project at Harvey Mudd College is to convert the current adaptive optics ophthalmic-imaging instruments from prototype/bench-top systems into a "clinical" instrument. The Harvey Mudd team will be responsible for the development of a next-generation ophthalmic imaging instrument that incorporates new design features aimed at improving the clinical utility of the instrument, for instance, by reducing its size and by making it easier to be operated by a trained technician. The HMC team will implement a broad range of optical, mechanical and software improvements required to make these changes.

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Soot particles are a common byproduct of combustion. These sub-100-nm carbon particles can lodge deep in the lungs, leading to cardiovascular and pulmonary health problems. They also contribute significantly to air pollution and potentially to global warming. Recent work has clarified the absorption and scattering properties of bare carbon particles in sunlight, but impurities in fuel often produce carbon particles coated with significant layers of sulfur and other dielectric compounds. To understand the role carbon aerosols play on global climate, and potentially to build remote optical diagnostics of soot emissions, it is necessary to measure the optical properties of these coated nanoparticles.

The goal of this clinic is to characterize the light absorption and scattering properties of coated soot aerosols. Soot particles will be generated in the lab by partially combusting ethylene and subsequently coated via a particle coating condenser. Their optical properties will be determined using angle-resolved scattering and cavity ringdown techniques.

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This year's project continues the work of last year's on vibrating beam angular rate sensors, but aiming to develop an over-size working prototype compatible with MEMS production techniques.

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Vibrating beam angular rate sensors were first proposed in the 1960s and have been manufactured in bulk since the 1970s. A high-Q prismatic beam vibrating in its fundamental resonance, and simultaneously rotating about the beam axis, experiences a Coriolis acceleration that induces a vibration perpendicular to both the driven vibration and the angular velocity. This induced vibration is proportional to the rotation rate, producing a signal that can be used to measure the rotation direction and rate. The team is investigating the feasibility of producing vibrating beam angular rate sensors using standard silicon micro-electrical mechanical systems (MEMS) technology.

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One subsystem of the Space Interferometry Mission (SIM) is to measure the small change in distance between two fiducial points to an error of approximately 50 pm. The method for determining this change in distance involves the use of a heterodyne interferometer. By dithering the beam of the interferometer in a known pattern about a fiducial point on the face of a corner cube, it is possible to align the beam such that the distance measured is minimized. This ensures proper alignment of the interferometer and proper measurement of the distance. We will focus first on creating a test setup here at HMC, and then on using this setup to break down all of our sources of error, such that in combination with the more expensive setup at JPL, we can meet the 50 pm requirement. Proposal

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The Jet Propulsion Laboratory Clinic team investigated various behavior aspects of a novel magnetotactic bacterium, LA-ARB-1. Aerotaxis, phototaxis, motility, and viability studies were the focus of the teams investigations. Results from their work contribute to a better understanding of how LA-ARB-1 uses its internal structure to take advantage of its unique environment.

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Etec Systems, Inc. is a worldwide leader in the designing, manufacturing, and marketing of mask-making solutions for the semiconductor industry. Our Clinic team is providing Etec with a feasibility study on a potential technology for tightening the focus point of a laser on the photoresist layer of a mask beyond the normal diffraction limit, enabling the writing of smaller mask features. We report both analytical and experimental results.

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Optivus Technology uses a proton accelerator as a radiation source for treating cancer patients. The current method of attacking tumors with the proton beam has been successful, but Optivus would like to improve the treatment by using a raster-scanning technique, requiring a much tighter control on the beam intensity. Our goal is to develop an improved electronics system to process the output of a beam intensity detector, allowing a feedback loop to control the beam at a much higher bandwidth.

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The Jet Propulsion Laboratory Clinic team constructed a modified Michelson interferometer to combine the light from two 10-meter Keck telescopes situated on the island of Hawaii. The system combines two 1" infrared beams of light from the telescopes and incorporates feedback control to ensure that the optics are correctly focusing the collimated beams into fiberoptic cables. The telescope system will allow for the direct detection of Hot Jupiter planets in other solar systems.

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Aerojet's current Advanced Microwave Sounding Unit (AMSU) orbits the earth, passively measuring the intensity of particular microwave frequencies for meteorological purposes. The team has explored and analyzed a number of new and innovative technologies in an effort to reduce the size and manufacturing cost of the AMSU receiver subsystem. Extensive research was done to determine the fundamental properties of the different technologies in order to pinpoint their limitations and foresee possible advances. The team has proposed feasible alternatives to the design of the current AMSU.

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The clinic team investigated and developed models for the reflection of the sun off the ocean's surface to create an improved "glitter" routine for Arete Associates' RenderWorld, their software package for modeling natural scenes. Current software techniques do not allow for efficient simulations of light reflection off small-scale water waves (referred to as glitter) because it is too computationally intensive. The team developed a software implementation of its recommended solution to Arete Associates. Images generated using the RenderWorld's package will be shown.

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The team designed and built a system for a massively parallel automated fluorimeter. The source provides bright, stable, spatially uniform light across the underside of the 11 cm by 11 cm sample tray in any six narrow bands in the visible and near UV spectrum. The team used compact high intensity arc lamps, holographic diffusers and dichroic optics to develop a system that outperforms the existing source at SAIC while costing one-third as much.

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BHK requested a design for a deuterium lamp that has a higher output and greater lifetime than existing lamps on the market. The team developed a model relating to such parameter as fill composition, pressure, and geometrical measurements to the intensity and spectral characteristics of the output, and suggested and evaluated design modifications to improve performance.

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The Fourier Transform Spectrometer (FTS) is a widely-used instrument for spectral analysis of thermal sources. The interferometry based FTS has a limited field-of-view (FOV). Gencorp/Aerojet has contracted the Harvey Mudd College Engineering/Physics Clinic team to determine the feasibility of a field-widened FTS. Extensive research has been carried out towards the understanding of both internal and external FOV constraints of the FTS. The focus on internal constraints has led to several interferometry design approaches; the most promising design utilizes a mechanically deformable cat?s eye mirror, which in place of the traditional plane moving mirror, allows for change in the curvature of the mirror as the cat?s eye is moved. Alternate designs include lens focusing systems and the addition of dispersive media. The team explored these prospective designs for a field-widened system through feasibility studies and performance evaluations.