Mack offers blind spot detection system to protect vulnerable road users

truck type key TerraPro
New PreView active system deploys radar to prevent accidents in LCOE blind spots


Great advances have been made in recent decades to protect motorists and truckers in accidents. Even more progress has been made to reduce vehicle accidents in the first place. Now, Mack Trucks is improving safety for pedestrians and other “vulnerable road users” (VRU) by detecting VRUs and alerting drivers so they can avoid them.

Mack now offers the Sensata Technologies PreView multi-sensor collision warning system for the Mack® LR, Mack LR Electric and MackTerraPro models, since these trucks are frequently in operation where VRUs might be present.

For example, 95% of refuse collection occurs in populous urban or suburban settings, such as neighborhoods, schools, apartment complexes, office parks, says Josh Seiferth, Mack cabover product manager.

220510 - PreView safety system-min
Sensata Technologies PreView multi-sensor collision warning system provides blind-spot object detection for the Mack LR® and LR Electric, and the Mack® TerraPro models.

The term “VRU” covers anyone who is on or alongside a roadway without the protective shell of a vehicle enclosing them. VRUs include, but aren’t limited to, cyclists, pedestrians, persons in wheelchairs, police, other first responders, roadway workers, skateboarders and scooter riders. The National Safety Council (NSC) also considers motorcyclists as VRUs, given their lack of vehicle enclosure and higher risk of injury in a collision.

VRU may be a new term, but the need to define it results from a marked increase of fatalities in that category. “Vulnerable road user fatalities have been increasing in the U.S. at an alarming rate,” according to an NSC policy paper. “In 2016, there were 5,987 pedestrian fatalities, a 9% increase from 2015, accounting for 16% of all traffic fatalities. Motorcyclist fatalities exhibit a similar trend, with 5,286 motorcyclist fatalities in 2016, a 5% increase from 2015. Bicyclist fatalities exhibit these increases as well with 840 bicyclist fatalities in 2016, a 1% increase from 2015.”

If the U.S. were to eliminate crashes involving vehicles and VRUs, over 11,000 lives could be saved each year according to the National Highway Traffic Safety Administration.


These statistics demonstrate the need to find solutions to the threat vehicles pose to VRUs. As NSC put it, “eliminating VRU fatalities and serious injuries will require a variety of strategies moving forward.” This includes eliminating existing risks concentrated in urban and suburban settings, where the threat is greatest. 

Advancements to protect VRUs are being pursued by safety advocates, government agencies, and other concerned groups such as commercial road users and their suppliers. Recognizing the danger to VRUs is greatest in cities and suburbs, Mack engineered the Sensata Preview technology into its low cabover engine (LCOE) trucks, the TerraPro, the LR and the LR Electric models. 

These LCOE Macks primarily work in refuse operations and construction applications. “Both refuse and construction trucks operate in close proximity to VRUs on city streets and suburban roads,” says Mack’s Seiferth. “That’s why we launched the Sensata Technologies Preview active-safety system on our LCOE trucks. This system is specifically designed for trucks operating in urban and suburban stop-and-go environments.

Always on

“VRUs are basically defined as people without a ‘cage’ around them,” he continues. “The key advantage of the PreView radar sensors is they are always on. The sensors recognize objects, including VRUs, regardless of the truck’s speed and even when the truck is stationary. This system helps our customers mitigate the risk of accidents for their drivers while improving the safety of persons on the roadways and side streets where these trucks operate most.”

“This system helps our customers mitigate the risk of accidents for their drivers while improving the safety of persons on the roadways and side streets where these trucks operate most.” Josh Seiferth, Mack cabover product manager

The Sensata system is driven by a set of radar sensors – one on the front, one on the rear, and one on each side of the vehicle – that detect objects and vulnerable road users in the driver’s blind spot. When something is detected, an audible alert sounds and a display on the A-pillar flashes, alerting the driver to an object or VRU in their blind spot. The system does not require maintenance.


Full array

The PreView sensor array and warning displays provide the driver with valuable safety feedback in a variety of situations.

  • PreView LH and RH sensors detect moving objects. When the truck is not in reverse, and the turn indicator is not activated, the system will alert the driver to moving objects by illuminating a light on the A-pillars inside the truck’s cab. When a turn signal is on, and the system detects a moving object on the side indicated by the turn signal, an audible alert accompanies the indicator lights. Above 19 mph, the driver side and passenger side sensors also assist the driver with lane change maneuvers – again by detecting vehicles or VRUs adjacent to the truck.
  • The PreView front sensor detects both moving and stationary objects and alerts the driver to the object closest to the truck. Front radar detections are ignored when the truck is in reverse. The front radar gives the driver visual alerts (lights flash) when an object is detected at the outer edge of its detection zone. Audible alerts are added to the visual alerts when the object gets closer to the truck.
  • The PreView rear sensor operates similarly to the front sensor, but only when the truck is in reverse. However, it provides both visual and audible alerts if it detects anything when the truck is in reverse.


The PreView active-safety radar system is available as an option and is factory-installed on new trucks. Customers may also retrofit PreView to their trucks by contacting their local Mack dealer. “The PreView system helps mitigate the risk of accidents for drivers and improves the safety of those on the roadway with heavy-duty vehicles,” says Seiferth. “Mack is proud to be one of the first refuse vehicle manufacturers to deploy a system to help protect VRUs.”