Ford wanted to include its Blind Spot Information System or BLIS as part of several safety enhancements in the 2015 F-150 trucks, but needed some plastics engineering derring-do to pull it off on a cost-effective basis.
Ford first introduced the Volvo-developed system in 2009 in the Ford Fusion and other vehicles, installing the sensor behind rear plastics fascia panels. But the F-150 has a bumper made of metal that blocks the signals.
Engineers first looked at a concept to package the BLIS module below the lamp perimeter in a box structure. That plan would have cost $15 million to modify the D-pillar.
In the new approach, the radar is housed behind two layers of acrylic plastic in a three-shot lens tail lamp. The injection molded acrylic lens is designed as a cover for the module to protect it from direct impact, water, mud or snow. A cast aluminum door acts as a heat sink that allows replacement of the module instead of the whole lamp. A plastic heat sink may be used later to reduce weight.
The first shot of the process is a red opaque layer of acrylic over the radar sensor, which is inserted in the mold. In the second shot, clear acrylic is molded over the red opaque, forming the backup window in the module area. The third shot is a red transparent layer to form the rest of the lens.
The BLIS monitors blind spots either in traffic or in parking lots while backing out. When the sensor detects a vehicle in a blind spot it triggers a warning light in the side view mirrors. Use of the system in a taillight as opposed to rear panel is an industry first.
The technology is a finalist in the Society of Plastics Engineers’ Automotive Division’s 44th-annual Automotive Innovation Awards Competition. Category winners and the Grand Award winner will be announced tonight at an awards banquet.