In 2009 ARB engineers started a development program to produce an ARB driving light with a completely new design incorporating the latest LED technologies.
Unlike light bars that were growing in popularity, ARB required a light that was compatible with current bull bar designs and traditional driving light mounting points. They also needed to be a legal fitment which, in many states, light bars are not.
Many ARB customers prefer a combination of a spot and spread driving light due to the various driving conditions encountered in general off-roading. Most LED light bars on the market are considered great lights for slower off road driving where the ability to see great distances is not so critical. For ARB's new light to compete with the best the market can offer in Halogen and HID lighting, it needed to give not only the broad flood beam associated with light bars but also a spot beam with the ability to penetrate longer distances.
Integral to the design was the need for the light to be robust and suited to the conditions encountered off-road like the constant vibrations of corrugated roads, animal strikes and the ability to be submersed. With the general abuse that off-road driving can dish out, the light also needed to be serviceable.
During the development stage, many advances in LED and optics design meant that the LED array and circuitry changed numerous times. With many tens of thousands to be invested in tooling, this meant that the design of the light body needed to be 'future proofed' so that further advances in technology would not require re-tooling.
The final design utilises a pressure die cast aluminium light body that acts as a heat sink where the removable LED circuit board containing SMD LEDs mounts into the front face. The Hybrid Optics (reflector & lens) are then located within a retaining bezel and held in place by the polycarbonate lens. Any future advances in technology therefore only require changes to the circuit board and optics.
Although SMD (surface mount) LEDs run very cool in comparison to traditional resin encased LEDs, the circuitry and associated components that power them get quite hot, requiring large heat sinks and cooling fins with increased surface area to draw the heat away from the circuit board. This required that the light body be manufactured from aluminium but due to its round shape, a pressure cast aluminium body was preferable over an alloy extrusion used in light bars.
With the light assembly weighing close to 6.75 lbs, a mounting system was designed from TIG welded 304 grade stainless steel to ensure integrity under the harshest conditions. Stainless steel offers considerable strength over other designs and with a requirement to handle vibration, prototypes of the new light undertook Military Specification vibration testing on a shaker table by an approved facility in Melbourne. Attached to an ARB bull bar the shaker table put both the light and bar through severe testing, with both the light and bar mounts resisting fatigue and passing the test.