Harnessing three dimensional (3-D) design, printing and scanning in Hydrography

Michael Whiting - WA Department of Water , 25 November, 2016

The Department of Water’s Hydrologic Technology Centre (HTC) provides instrumentation and assets internally for both long term and project based measurement of Western Australia’s surface water and groundwater resources.

The HTC integrates a wide range of hydrographic instrumentation including transducers, data loggers, communication systems and power systems from different suppliers along with instrument mounts and site infrastructure for hydrographers to install and use in the field.

Since the mid-1960s these items were drawn using ink pens and drafting film.  This was replaced in the early 1990s by Autodesk® Autosketch® computer software.

Over the years fabrication was done in-house, which required qualified machinists and workshop facilities. With increasing pressure on resources, fabrication was systematically outsourced requiring accurate documentation for contractors to follow.

In an effort to improve this process and reduce costs a more robust industrial approach to design and documentation has been implemented. The process uses 3-D design software, 3-D printing and 3-D scanning technologies.

Using 3-D design software requires an item to be modelled in a virtual 3-D space, which is then used to produce accurate drawings and outputs for computer controlled laser cutters, benders etc., all of which are handled in the one computer application Autodesk Inventor®.

Although visualising a product on screen is possible, having a physical object to trial its use is far more effective. However fabricating prototypes to trial a design can be very expensive. 3-D printing is a technology that has become more common place and more cost effective alternative which allows items to be replicated quickly in plastic resin, tested, re-designed, and 3-D printed again as required before finalising the design.

Complex items either don’t have electronic drawings available or the cost of modelling the products from manual measurements is cost prohibitive, so 3-D scanning was trialled. 3-D scanning is undertaken by taking snapshots of the surface of a product and an electronic model of the surface is developed which can then be used to design other items to fit or integrate effectively.

The paper will not only provide an overview of the technology, processes and challenges faced in adopting this 3-D design and documentation approach to instrument mount and site infrastructure design, but also provide real-world hydrographic examples of how these technologies have been used to great effect.