Generate - Imagine Analog

Imagine Analog was founded on the idea of using field-programmable analog array (FPAA) technology to provide users with an instantly configurable, fully analog audio effects unit for guitarists.

Digital effects pedals give the guitarist access to many different effects, but are limited to the computational capacity of the board, resulting in latency issues. Analog pedals are limited by the pre-existing effects on the board, but FPAA technology gives the user the bredth of effects that digital pedals do while bypassing computing limits like standard analog pedals would.

I was a Hardware Mechanical Engineer for Imagine Analog, one of two mechanical engineers on the team. I learned how to design electromechanical systems, and how to design around sheet metal.

Final Showcase Build

Final Assembly CAD

Subsystem: Pedal Mechanism

Problem: Design a pedal mechanism that will allow the user to set the desired amplification using their foot, then save the effect when the user releases their foot.

Action:

Consulted with EEs to select pedal-potentiometer design to control amplification effect
Selected gear mechanism to translate pedal to potentiometer rotation based on market research, ease of manufacturability, and cost
Designed custom pedal to interface with custom gear around potentiometer. 10:1 ratio selected based on 300-degree range of motion of potentiometer and 30-degree desired pedal range of motion
Designed pedal and potentiometer mount with custom potentiometer gear to couple with wall-mounted, rotating shaft to prevent cantilevering of potentiometer
Chose 3D printed pedal and custom gears as final prototype due to high cost and manufacturing difficulties of metal or plastic machined parts
Added rubber stoppers at ends of pedal to prevent damage from wear or excessive pressure

Pedal + Shaft Bearing Mount

Pedal + Potentiometer Mount

Final Assembly Pedal

Result:

Effect was amplified directly with each degree pedal was pressed
Pedal mechanism operated smoothly over 2+ hours of operation
Received positive feedback that pedal was “user-friendly” and was “satisfying” to use
New users are product showcase were able to set desired amplification with precision, and pedal would stay stationary when a user’s foot was removed, leaving the amplification unchanged when not pressed
Displayed final CAD at showcase with functioning 10:1 gear ratio between pedal and potentiometer

Subsystem: Main Body Frame

Problem: Create a sleek outer-body frame that will support and enclose all relevant components, stay robust after many uses, and make the product appealing to a user.

Action:

Helped design ideal rendering with designers, selecting matte-black aluminum frame for CMF based on existing products within target price range, stability of frame, and ease of assembly and manufacturing
Determined body dimensions based on electrical and mechanical constraints while maintaining a smaller footprint than similar products
Designed for integration of electrical components, using block CAD to locate components with efficient use of space, designing cut outs and mounts for USB, stereo jack, foot buttons, LCD display, and rocker switch bulkheads.
Designed internal corner brackets with heat set inserts to assemble 6 outer body faces without any protruding screws
Ordered precise laser-cut sheet metal frame with screw countersinks through Protolabs, but had to hand-cut and spray paint sheet metal due to supply chain issue
Added rubber stops at base of frame for stability and to prevent wear of sheet metal

Result:

Presented fully assembled prototype at showcase, with raspberry pi microprocessor, power supply, and breadboard mounted inside frame
Received positive feedback on “professional” and “high-end” design
Electronics worked seamlessly with frame – users were able to press buttons with feet, control LCD touch screen, access and use USB and stereo jacks
Professional, laser-cut frame arrived after product showcase.

Initial Ideal Pedal Rendering

Electrical Component Block CAD

Heat Set Bracket Design

Laser Cut Sheet Aluminum

User Demonstration at Product Showcase

Working Multi-Effects Pedal