I have been working on various productivity tools for PD engineers

Hi-Lite Sports was developing a system to record live youth sports games with a high-resolution camera based on 2x 4K camera modules packaged in a portable case and mounted on an extending pole to capture the full sports field in the camera field of view. Proprietary software could then digitally zoom and pan to capture action as needed after the fact. I helped to create a system schematic and associated mechanical/interconnect layouts in the mast head and case based on their high level specifications. I also designed mechanical brackets and enclosures including a mounting/calibration scheme before building prototype.

HLS1

HLS2

I collaborated with Per Welinder, a member of the bones brigade skate team turned founder of birdhouse skateboards and Welinder-Shi capital on a concept for an electric skateboard in a street board form factor.  The idea was to provide just enough assistance to a rider to have a meaningful impact while minimizing the battery capacity and motor size to reduce cost and weight and enable greater portability compared to popular-at-the-time long board electric skateboards. I first built an analytical dynamics model to identify the amount of power needed to overcome rolling resistance, air drag, and inclines across different use cases, speeds, and wheel sizes. This model showed that there was a limited cost to using smaller wheels, and that the increase in power consumption was non-linearly related to velocity and acceleration. Using the battery capacity allowed on an airplane as a reference point, I then developed a design integration that leveraged as many traditional parts as possible and did a cost, supply chain, and mass analysis. I also instrumented a skateboard with an inertial motion tracker to monitor the acceleration and deceleration profile of a skateboard during a series of pushes and architected a control system that would intelligently apply power assist curing a push and glide based on the profile. We did not move forward with the concept but did go on to explore different packaging concepts for other skateboard form factors through mass-market distribution channels before both getting pulled away into other projects.

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SKT4

I collaborated with Michelle Steilen, a professional freestyle roller-skater and founder of Moxi roller-skates, to develop an attachable grind plate that allowed skaters to do tricks in skate bowls and half pipes. The plates were designed to be low cost, low profile, easy to assembly, and reflective of the Moxi design language. We built several rounds of prototypes and tested them in Lauren’s half pipe but did not pursue the concept further as I was pulled into other projects and Lauren went on to a focus on developing a footwear company.

MX1

I designed and prototyped a scale vehicle with configurable mass and buoyancy distribution for testing in a wave tank in order to validate the fluid dynamic relationships of the control surfaces. Because of the sensitivity of the geometry, I built large custom silicone molds internally and molded/finished several sets of prototypes.

Translucence Bio is a pioneer in tissue clearing and staining with the i-disco method used for high resolution brain imaging. In this process, an animal brain undergoes a sequence of treatments with various fluid mixtures over a month-long process to clarify and mark the tissue so that it may be imaged using light field microscopy. This equipment, funded through an SBIR grant, automated that process in a high throughput configuration. Eight reagent mixture reservoirs were combined in specific proportions and then passed into addressable reactors comprised of off the shelf sample containers mounted to a custom cap in which the samples were stored. Positive displacement piston pumps were cost prohibitive, so we had to develop alternative methods for managing fluid metering and transport.

TLB ID1

TLB ID2

In the initial proof of concept design and prototype, we coupled commercial peristaltic pumps with an air pump, which allowed for open loop draining, filling, and flushing the reactors using a minimum number of low-cost commercial valves. The reactor banks were mounted to a mechanical stage which would invert to mix the samples and was also critical in the filling and draining protocol. In addition to designing and prototyping the reagent delivery system and reactor banks, I also designed, prototyped, and characterized a Peltier-based thermocycler chamber in which the reactor banks were installed.

TLB1

TLB2

The open-loop proof of concept prototype performed within target performance specs for fill accuracy and speed when used with medium and large sample volumes but did not achieve the target goals for small sample volumes. After exploring the source of error and root causing it to imprecision in the peristaltic pump that varied with environmental conditions, we concluded that a closed-loop system was needed.  No commercially available flow sensors within budget could accommodate the full dynamic range across all sample sizes while still supporting target fill times, so we developed a concept for a mass-based approach using a microbalance, and a volume-based approach using a conical burette coupled with pressure sensing or machine vision. Closed loop capability also allowed for the reagent dispensing scheme to be further simplified.

TLB volume 1

TLB volume 2

TLB mass 1

TLB mass 2

TLB dispensing 1

During the next design cycle we also wanted to investigate a more production form-factor integration considering usability, construction, and electronics integration. I developed a mechanical design and system schematic/interconnect strategy before bringing ID in to do a design round. At this point we had met the goals of the original grant proposal so paused development in anticipation of a phase 2 SBIR grant to take the development through low volume commercialization.

TLB schematic

TLB layout

Sempulse has developed a patented technology to capture vital signs for first responders, military personnel, and other applications using PPG, ECG, and body temperature sensors packaged in a small ear-worn device that takes advantage of the increased profusion behind the ear. I helped to design and prototype the mechanical enclosures, battery compartment, interconnect between the sensor unit and main unit, as well as body attachment methods. I also proposed test protocols and functional metrics related to validation efforts. Years later I also built an on-the-line test fixture for validating PPG and ECG performance.

SMP

Mirror Cache is commercializing a smart mirror for use in hotel rooms that couples an LED display with a semitransparent mirror and associated computing components. I delivered a sheet-metal-based mechanical integration of preselected components and interconnect strategy that was manufacturable in low volumes, thermally viable, low profile, and serviceable. I supported prototyping an pilot production by a partner kiosk vendor.

MRC

A startup company had acquired a patent for sensing blood flow over the radial artery and inferring blood pressure. The conceived device included a wrist-worn processing and communication unit coupled to a PPG sensor integration in the watch band. I engaged to propose a development path for a commercial device and subsequent FDA-compliant device and then designed and prototyped a reference integration and form factor. Next, I found an existing development platform from Maxim and designed a prototype device built around the available electronics that was used for human trials. I research PPG sensor fundamentals as well as state-of-the-art low power sampling schemes and signal processing algorithms to propose a set of requirements and performance metrics. In particular, I developed a series of molds across band sizes to encapsulate system interconnects in an elastic cast-silicone watch band combined with an optically clear silicone over mold in the sensor region. I also supported a follow-on effort to architect a watch-band-only device for use with different luxury wristwatches.

VSC

I collaborated with a pest control industry veteran to develop a low-cost device that can detect when a rat trap has been triggered and designed a user interface and digital administration platform. The consumable device is a tray that holds an industry-standard Victor wood mouse trap and includes a bistable spring arm that applies battery power to a transmitter when the trap is triggered. This enables a very simple and low-cost set of electronics that operate over long distances and adhere to FCC transmitting restrictions for the band. I contracted the design of transmitter assemblies based on an ATTiny microcontroller and built a set of mechanical prototypes to test with a commercially available hub and web service. I also designed and scoped prototyping a semi-custom back end and web service product for deploying and tracking triggered devices. I then researched the patent landscape and competitive devices and before proposing a go-to-market strategy. Without a clear path to commercialization, the project has fallen to the wayside but appears to solve meaningful industry challenges.   

RAT

Zipline is a delivery and logistics company successfully pioneering the utilization of autonomous drones. Their P2 platform consists of a highly aware quadcopter main drone with a tethered-drone payload. I supported their internal engineering teams with a variety of design and analysis efforts. All their components must be high performing, cost effective, and mass optimized which justifies a high level of design refinement and validation efforts.

o   Design and development of acoustic sensor probes. The wing-mounted probes position microphones at a prescribed distance from the control surfaces for detection and awareness. The probes had to be quickly swapable, facilitate interconnect to the body, immune to resonance, and cost effectively manufactured. Additionally, they need to “break away” during incidental impacts to prevent damage to the vehicle. We developed and prototyped several mechanisms concepts and system integrations and then carried a preferred embodiment through to detail design. The design met all the requirements with elegant and innovative solutions.

o   Prop motor structure design and analysis. I worked with the motor team to develop mechanical structures for the primary motors using analytical modelling combined with structural and modal FEA software. We were able to identify mass optimized designs within the manufacturing limitations across a range of integration variables that were interdependent with other systems such as prop offset, bearing stance, etc.  I supported validation and data analysis efforts throughout.

o   Fan integration and manufacturing. I also worked with the motor and aerodynamics teams to develop fan integrations for the drone device. I took desired fan blade geometry from the aero team and went back and forth with them and the fan vendor to develop manufacturable design that were mass optimized and had resonances outside of the operating window. I also supported engineers developing structural elements interfacing with the fans to ensure that the system modes were also acceptably outside of the operating window

o   Folding prop mechanism I supported the design effort for a folding prop mechanism through an analytically-driven design effort with particularly challenging spring requirements and high loading.

o   Angle of Attack sensor I designed a vane-based AoA sensor integration that was significantly below the mass budget, compact, and easily manufacturable. And then validated performance with a custom test fixture.

o   Air speed sensor I designed a pitot-based air speed sensor that needed to be robust to debris, operational in freezing environments, and compact. I researched existing pitot integrations in aircraft and developed a design that met the requirements, was below mass budget had target thermal transfer characteristics and sourced a custom thin film heater. I validated the design with a quick and dirty data collection system in the before supporting handoff to a CM.

o   Training data collection devices I worked with the perception team to design and build two different contained camera data collection platforms that could be easily mountable to commercial aircraft and FAA compliant.

ZPL

Manscaped is a new entrant in the personal grooming market. They wanted to further develop their proprietary “skin-safe” technology. I began by characterizing and benchmarking competitive devices relative to blade construction and drive mechanism. I then developed a set of phantoms/surrogates for different types of hair on various body parts for bench testing and evaluation using a high speed camera. We were able to discern that there is an optimal blade pitch that ensures reliable cutting while limiting the potential for skin damage. We also tested three different concepts for additional elements/guards.

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MNS3

Matregenix is a startup specializing in nanofiber fabrics for a range of applications. While nanofiber filters have not gotten significant foothold in the aerosol filtration market, there is evidence that they may be able to outperform traditional spun bond filters relative to pressure drop and filtration efficiency due to their unique filtration phenomenology. A third party company was working with Matregenix to quickly establish a mask production line during the initial stages of Covid-19 and I was engaged to assist with mask engineering and production line layout. In parallel to 3rd party efficacy testing I research different mask ratings and requirements, helped engineer a mask design that was compatible with the mask production cells being sourced for the project. The company secured a local industrial spaces and we produced a layout and scaling plan. When the third party efficacy testing did not produce the desired results and the mask availability landscaped changed the company reversed their plans after one cell was completed.

NF

 A consumer good company was developing a foldable cooler. I built a thermal model against a set of performance requirements to facilitate material and thickness selection in conjunction with a mechanical folding design and manufacturing plan. I then mocked up representative elements and built a custom test fixture to validate the thermal behavior of the design before building a prototype of the full design and folding mechanism.

CM1

I developed a concept to aerosolize a fluid using an orifice sprayer

Spray1

Sprayer Concept