Preco Display: Durable Enclosure

Case Study

Expertise Applied

Concept Development
Industrial Design
Durability Engineering
Enclosure Design
Materials Research
Component Selection
Manufacturer Engagement
Design for Manufacture

About this Project

Preco Electronics produces vehicle-mounted radar warning systems for commercial vehicles and heavy equipment. Their PreView products provide blind spot monitoring in a commercial-grade package. The systems consist of radar sensors that mount to the outside of vehicles, plus a display unit that provides an audible alarm and visual indication to the driver / operator. The PreView product line was well established, but was in need of an update. Specifically, the in-vehicle display was aging. Preco was interested in developing a new display unit with specific features and characteristics.

Preco engaged SGW Designworks for full enclosure design and DFM for the entire assembly. Specific design features requested by Preco included:

IP-69K rating: high pressure, high temperature wash-down resistance
A clean, new look compatible with industrial applications, and with existing Preco products
Provide increased speaker volume, sufficient to hear inside a noisy vehicle
Integrated ambient light sensor to auto-adjust LED indicator brightness / intensity
Incorporation of a multi-function button for specific user inputs and use-cases
Definition and incorporation of a flexible, modular mount
Assembly and tolerance stackup: 2 PCBAs, connectors, sandwiched between housing components

Approach

SGW’s initial work focused on definition of a look and feel compelling to Preco, that was new but at the same time compatible with legacy Preco products. While multiple industrial design concepts were developed, engineering efforts focused on the highest-risk item: achieving the IP-69K rating in a product that incorporated a button, lights, and a speaker.

A winning design language was developed by the team, and the engineering team incorporated it into the preliminary design. Next, a clever mounting system was developed and integrated. With the form-factor defined, multiple engineering paths to achieve the IP rating were explored. In addition to the rating requirements, the SGW team identified a new challenge: Tolerance stack-up. How would the contract

manufacturer able to deal with material and component variances while still achieving the seal required for the IP-69K rating? The answer was to design the assembly for a sonic welding process. This meant a vent would need to be incorporated, which SGW Designworks defined in collaboration with W.L. Gore, the pioneers of Gore-Tex. The vent was incorporated into the housing design. Next, the team identified a speaker that could provide the volume, in which the speaker diaphragm could provide a IP-69K compliant seal.

Incorporation of the speaker into the design required special engineering considerations. To function properly, the speaker mounting points were designed so that the speaker is maximally exposed, but with minimal capture.

This had a big impact on the overall internal design of the housing. The user-interface button was designed with the actuator built into the main hosing element, and them over-molded for sealing.

Incorporation of light pipes was the most effective way to provide the right visual alerts to drivers while still achieving the durability targets of the product. Like other design decisions, this would impact the production and assembly methods used to manufacture the product. SGW Designworks engineers collaborated with Preco and with contract manufacturers throughout the design development process. This was critical, because the complex assembly could become costly to produce without incorporating manufacturer input along the way.

Results

This project was an enclosure development effort, first and foremost. Experienced product developers and engineers understand that when durability and reliability are must-haves, projects that would otherwise be simple can become complex. Incorporating user input elements, speakers, and visual indicators while achieving stringent ratings like IP-69K is challenging. By prioritizing risks, exploring multiple solution paths in parallel, and collaborating with contract manufacturers, it is possible to develop a robust solution that meets market needs, within the target development budget. The Preco PreView Display was launched as part of the Preco Side Defender II system in early 2019, and is already gaining traction in the market. In October of 2019, the product won an Idaho Innovation Award for Commercialized Innovation of the Year.