Based in New Zealand, 3D Hub Ltd., a product development company specializing in mechanical products, has been involved in helping companies turn product ideas into assets and reducing manufacturing costs with computer-aided engineering (CAE). 3D Hub now uses 3D scanning as part of its service catalogue, which features product and industrial design, mechanical design, reverse engineering, structural optimization, prototyping, CAD modeling, finite element analysis (FEA), and much more. Among its many projects, 3D Hub has placed a central role in adapting American left-hand vehicles for right-hand drivers in New Zealand and Australia.

The Project

3D Hub was called upon to convert a left-hand heating, ventilation, and air conditioning (HVAC) unit into a right-hand unit to fit the modified interiors of Chevrolet and GMC trucks. The project was carried out both at the customer’s premises and 3D Hub’s offices. The entire project took approximately three months to complete over the course of several visits.

The main challenge was the reverse engineering aspect to the project: the team wanted to develop a right-hand HVAC unit by acquiring the 3D measurements of the current left-hand components and integrating them within a CAD environment so that the designs could be converted and then manufactured via the company’s 3D printing processes. “All the complex functionalities had to fit into a right-hand space that was smaller than the original left-hand HVAC unit. Moreover, the reusable components, such as fans, sensors, servo motors, airflow flaps, etc. had to be integrated in the CAD design,” explained Craig Russell, Director and mechanical engineer at 3D Hub.

Converting the HVAC

The HVAC unit was one of a number of components (dashboard, steering column, electrical) that were to be converted for the opposite layout. This was not going to be a simple mirror image. The first step was to disassemble the truck. The original dashboard was cut into critical sections (glove box, centre console, etc.) and moved to their new positions on the right-hand-side of the vehicle. The dashboard components were mounted onto the dashboard support bar and then removed as one from the vehicle. The dashboard pieces were then joined, hand-shaped and formed to create the final dashboard. From this final shape, a plug was made to create future fiberglass dashboards.
Meanwhile, the steering wheel and column were removed and repositioned to fit in the opposite side of the engine bay.
With the dash removed, the original HVAC unit could be removed and the firewall easily accessed for 3D scanning. First, positioning targets (datum targets) were applied onto the firewall surface. Note that, for this project, the positioning targets would not be removed before the end of the project: they would prove to be useful for precise positioning and alignment later in the development process.

Reverse Engineering

With the HVAC removed, it could be reverse engineered. 3D Hub began 3D scanning the HVAC. The 3D scan data was used to lay out the new HVAC with its major components. The recirculation unit was positioned in the vehicle to verify fit and final placement. Once it was in the final position, it was scanned relative to the original positioning targets on the firewall. This data was brought into the CAD environment in exactly the same place; no alignment was necessary thanks to the retained positioning targets throughout the project, which significantly reduced processing time.
Once the reformed dashboard was completed and positioned in the vehicle, 3D scanning enabled operators to inspect the underside of the dashboard with the electronics and ducting in place. The scanned data was aligned to the original target location on the firewall. The HVAC unit could then be checked that it cleared critical components like dash bar, glove box etc.
The converted HVAC unit was now ready to be 3D printed in SLS nylon. The prototype was mounted and tested in the vehicle. Due to the accurate scanning data, only minor adjustments needed to be made before a final product could be manufactured and could perform to the same high standards as the OEM unit.
Although this reverse engineering project could have been carried out using other 3D scanning technologies, it would have certainly required a longer preparation time. The use of a HandySCAN 3D, as opposed to other 3D scanning technologies or mounted scanning systems, was the best option. The HandySCAN 3D’s flexibility, auto-positioning and fast and accurate localization of the part ensured by the positioning targets was key in selecting the equipment to carry out this project. “The ability to scan anywhere, move the parts during the scanning process, and split the job up over periods of time was what made us choose the HandySCAN 3D,” explained Russell.
“Scanning is now an integrated part of our design development process. This particular reverse engineering project and the outcome for the customer led to a referral to another company who does similar work in Australia.”
3D Hub’s initial work with the HandySCAN 3D clearly demonstrates how the scanner can be easily and effectively used for all types of reverse engineering projects, including those that involve subsequent 3D printing of the components to accelerate the overall manufacturing process.