Design Build Test

Overview

  1. We start with an initial consultation to determine the scope of the project, timeline, and to answer any questions about the process. This has no fee. You can get a jump start by answering this short questionnaire.

  2. After discussing the details of the project scope, I will provide a proposal and a time estimate (if applicable). We can iterate. If you agree to the terms, work on the project will start.

  3. While work is in progress, I will provide you with updates on progress and milestones. We will review the design at each major milestone before progressing.

  4. At time of delivery, you will receive all source files for your project such as design documents, data sheets, CAD files, and fabrication documents. For projects that include fabrication and assembly, you will receive all assembled units and any excess. You will be provided an invoice which is transparent and itemized for all time and materials.

What follows is an outline of a common project workflow. Many projects start by providing me with the conceptual design and requirements for the device. If you don’t have those, don’t worry! We can start there and I can help you develop these. Having good documentation here means no one gets surprised.

Note: Some projects are highly experimental in nature (e.g. new product introduction) or sufficiently complicated that it is not always feasible to produce an accurate estimate for the total time required to create a finished device or product. An iterative development approach is usually proposed in these cases.

Design

Conceptual Design, Architecture, Specification

We define the user and product requirements. Then we create a high-level design for how the device will meet those requirements.

Some of the documentation we will create:

  • What function does this device perform?
  • How it will accomplish that goal: individual subsystems, interfaces, block diagrams
  • Mechanical requirements such as size, enclosures, and location of connectors
  • Whether seeking certification / approvals such as UL or FCC
  • How will the device be tested?

Circuit Design and Schematic Capture

schematic Parts are selected, a parts library is created, and the schematic is drawn.
simulation Sensitive circuits such as analog circuits or transmission lines may be simulated.

The schematic is reviewed and approved. A bill of materials (BOM) is created.

Printed Circuit Board (PCB) Layout

layout We might want to start off with mockups to investigate fit, form, and function of enclosures, buttons, display locations, connectors, etc. These might be digital 3D models or 3D prints.

A “stackup” is determined for the complexity of the board. Roughly speaking, this is how many layers are required to connect all of the components while meeting performance needs. The layout is then created.

Fabrication and assembly documents are created.

For complete product designs, a “master BOM” is created that includes all required components to produce the device. This includes things such as the PCB, PCB components, antennas, power supplies, cables, enclosures, fasteners, adhesives, printed manuals, etc.

Build

Mockups

3D models and prints may be created to test fit, form, and function.

enclosure 3dprint sub assembly

Fabrication and Assembly

assembly

A printed circuit board assembly (PCBA) is produced.

Test fixtures are created. Any necessary cabling or accessories are also procured.

For mature products that only require “line testing”, PCBAs are fastened into enclosures, cables and antennas are attached, etc. For new designs that are still being verified and validated, see the next section on Test.

Note: A guaranteed two week turn-around time on producing PCBAs is the standard “fast” and comes at a premium. A one week turn-around on a new design will come at a very high premium. Some assemblers can turn an assembled board around in less than a week but this is not usually a sustainable development cycle. Some turn-key solutions might require payment to Grizzly Peak Systems for materials before fabrication and assembly can begin.

Firmware

Development of basic bootable firmware and software is often started while the device is being manufactured.

Test

Programming and Test Fixtures

Depending on the complexity, sensitivity, or number of PCBAs, a test fixture might be created which connects to the device to test its functionality. This same fixture is often responsible for loading software onto the device.

Field Testing

field testing

A second device is often created to test or “drive” units deployed in the field (or during install at the site). These are often low-cost commercial off-the-shelf devices wrapped in shrink tubing. In other situations, it is a second much simpler PCB design in a proper aluminum enclosure.

Note: It would be an error to not mention that for some industries and applications, the test plan and test fixtures are far more sophisticated than this and can be 50% or more of the total work on a project.

“Bring Up”

The device is tested for manufacturing defects (this is usually short circuits and open circuits). The device is then powered up in a controlled fashion.

Software is loaded and functionality is tested.