What would you do if you were driving down the road and you could not see any of the lines? How would you stay in your lane? How would you know where to go? This situation is the reality on many roads in the United States and around the world. This is made even more challenging in inclement weather conditions. The problem is so prevalent, the American Society of Civil Engineers recently rated U.S. roads with a grade of “D+.”¹ The problem is compounded when autonomous vehicles (self-driving cars) are included. If the human drivers can’t see the lines, the computer-driving vehicles will not either. It is the general consensus in the AV industry (though lesser known to auto manufacturers and the general public) that improving road markings is a top obstacle to be overcome before Level 3 classification (conditionally automated AV) can be realized. At a failed demonstration of self-driving car technology at the 2015 Los Angeles Auto Show, Volvo’s North American CEO, Lex Kerssemakers, exclaimed, “It can't find the lane markings! You need to paint the bloody roads here!” The Autonomous Vehicle industry and developers stand to be hit hard by delays caused by limitations of current road marking infrastructure. By the year 2030, AV’s are projected to comprise 25% of traffic and are expected to be an $87B industry². Delays caused by road marking infrastructure will heavily impact early investors and developers as the expected market growth is reduced and competitors are allowed more time to get in the game. To most people, the stripes painted on the road are taken for granted. It's just a line painted on the ground. What's the big deal, right? In fact, there is quite a bit of engineering involved with applying the line to the pavement. Road stripes are critical safety features of the road with minimum standards recommended by local agencies, and the US Federal government very close to publishing minimum requirements³. Worldwide, it was estimated that in 2016, there were 1,366.2 kilo tons of coatings (paints, thermoplastics, preformed tapes, epoxies, etc) applied to the roads to help ensure good visibility4. This shows that the industry is very large and vital to ensuring safety of motorists. In addition to the different types of paints and thermoplastics used to create highly durable lines that can withstand the rigors of traffic driving over the top of them, night-time visibility is enhanced by embedding small glass spheres in the paint or thermoplastic material used to create markings. These beads act as retroreflectors, returning light from a car’s headlamps to the driver’s eyes. However, there are several process variables, including sphere diameter, sphere placement density, and the depth to which the beads are embedded, which affect the precise level of marking retroreflectivity, and therefore visibility, at night. As you might imagine, because of the minimum visibility requirements and ongoing safety research, there are tools that can help ensure road lines are clearly visible to both human and computer drivers. Gamma Scientific’s RoadVista division has been at the forefront of road stripe measurements for more than 40 years, having developed the first commercially available pavement marking retroreflectometer for 3M Company in the 1970’s. Now, RoadVista products are used extensively all over the world for managing road signs, road stripes, and reflective pavement markers. More recently, RoadVista has developed laser-based technology which can perform highly accurate visibility measurements of pavement markings while driving down the road with the speed of traffic and evaluating the performance of every line on the road. The system, called the Laserlux G7 (LLG7), incorporates one, two, or three diode lasers, with output at red, green, blue, and infrared wavelengths. Within the instrument, the laser beams are projected onto an oscillating mirror to create a horizontal laser line that projects out onto the road surface. The scan lines are projected out on to the roadway and the return signal is measured. Real-time analysis of the data gives the line’s visibility, both in terms of brightness of the line and contrast with the pavement, along with the line’s perceived width, color, and location. This allows the operator to quickly evaluate the performance of the lines, and locate problem areas that should be re-striped, both for human drivers and autonomous vehicle sensors. The key to making the system user-friendly was to make it easily deployed. To help with that, the engineers at RoadVista turned to Hollywood. External vehicle mounted cameras are commonplace in movies and TV where car chase scenes are prevalent. RoadVista saw that those mounting systems could easily be modified to accept mounting the LLG7. The mounting system utilizes high-strength vacuum cups that stick to any smooth vehicle surface and holds 20 times the weight of the LLG7, ensuring the system is completely secured to the vehicle. The LLG7 is powered by a 12VDC accessory outlet in the vehicle and is operated wirelessly via any tablet, smartphone, or laptop computer. The ease of use and data quality of the LLG7 goes a long way towards enabling wide scale measurement of the visibility and performance of pavement markings. Really all the operator does is attach it to the car, turn it on, and then drive around. The system automatically acquires the data, along with GPS coordinates, and stores this on a flash drive. Plus, the use of red, green, and blue lasers enables marking color measurement to ensure white is white and yellow is yellow. Alternatively, the utilization of an infrared laser enables measurements of the road the way many self-driving cars will see it. So, the next time you're driving down the road, take a look at those lines you're following. It’s more than just a strip of paint on the ground. Countless hours have been put in researching and formulating that stripe. RoadVista has played a key part in making sure that line is visible for not just you, but for the self-driving car that will be sharing the road with you very soon. Eric Nelson | RoadVista Product Line Manager 1. “Infrastructure Report Card,” American Society of Civil Engineers, https://www.infrastructurereportcard.org/ (2017). 2. “Self-driving Cars an $87 Billion Opportunity in 2030, Though None Reach Full Autonomy,” Lux Research, http://www.luxresearchinc.com/news-and-events/press-releases/read/self-driving-cars-87-billion-opportunity-2030-though-none-reach (May 20, 2014). 3. “Summary of the MUTCD Pavement Marking Retroreflectivity Standard,” Federal Highway Administration, Publication No. FHWA-SA-10-015, https://safety.fhwa.dot.gov/roadway_dept/night_visib/fhwasa10015/ (April 2010). 4. “Traffic Road Marking Coatings Market Analysis By Product (Paint, Thermoplastic, Preformed Polymer Tape, Epoxy), Growth Prospects, Value Chain Analysis, And Segment Forecasts, 2014 – 2025,” Grand View Research, http://www.grandviewresearch.com/industry-analysis/traffic-road-marking-coatings-market (June 2017).