Engineering

Company: Knowles

Roles:

• Mechanical engineering manger
• Lead designer and mechanical engineer (Solidworks)
• Structural, flow, and thermal simulation (ANSYS, CFX)
• Membrane shape simulation and material characterization (ANSYS)
• Spec definition and supplier technical DFM

Year: 2016

Key Patent: US20150028195A1

Detailed Description

The zoom lens project achieved 3X optical zoom in a form factor that is compatible with a mobile phone. The most compact 3X zoom camera ever created uses a novel approach with two deformable lenses to achieve zoom and focus. The camera also has a fantastic macro mode, with an ability to position the camera much closer than the 5-10 centimeters common with smartphone cameras. 

The lens deformation is achieved by pumping an optically-transparent fluid between a traditional lens and a thin silicone membrane. This effectively creates a doublet lens, with the fluid and the plastic lenses operating as a pair. The silicone membrane takes a shape close to a sphere, but with some "M" shape deviation, that can be characterized with the Zernike [4,0] coefficient. 

Designing a zoom lens of this scale is extremely challenging. Minimal tradeoffs are expected in all metrics of imaging performance including image distortion, sharpness (MTF), chromatic aberration, relative illumination, and stray light. Furthermore, factors like thermal compensation, size, focus time, and power consumption must also be considered.

Company: Knowles

Roles:

• Project lead
• Lead designer
• Lead mechanical engineer (Creo)
• Mechanical simulation (ANSYS)
• Fluid dynamics (CFX)
• System acoustic simulation with circuit analogies (LTspice)

Year: 2020

Key Patent: US10932069B2

Link to image

Detailed Description

Should an in-ear earphone have a large vent or be totally acoustically sealed? There are benefits to both designs. The acoustic valve seeks to give the best of both worlds by allowing the earphone to switch between an open and a closed state. 

With the valve in the open state, the earphone produces less annoying occlusion effects, is more comfortable, and the user can easily carry on conversations. With the valve in the closed state, outside sounds are blocked and the bass in music is much more pronounced. 

The valve must be bistable so that it consumes no energy when not being actuated. In one state, a spring dominates the force balance, holding the moving portion against a hard stop. In the second state, a magnet holds the moving portion against a different hard stop. The key to making the valve bistable is in the nonlinear magnetic force between the moving portion and the stationary magnet.

Note that the patent and the image from it are not the latest, some newer work is still pending publication.

Company: Northrup Grumman

Roles:

• Mechanical engineer (Pro/E - Creo)
• Structural simulation (ANSYS)
• Vibration subject matter expert

Years: 2009-2012

Detailed Description

Projecting aircraft from enemy fire is critical to the safety of our military, the military of our allies, and important heads of state. Infrared detection systems and countermeasures are a key part of that protection. 

My work included mechanical design, static structural simulation, gasket design, reliability simulation and testing, and vibration simulation. At Northrop I also created many tools to speed up and standardize simulation work products.

I will neither confirm nor deny exactly what products I worked on, but these images are certainly representative. A note to would-be foreign social engineers: If I knew anything you wanted to know, which I probably don't, I will not be disclosing it. So please don't even try. 

First Image Credit: Military + Aerospace Electronics

Second image credit: Airforce Institute of Technology