Avoiding Obstacles That You Can’t See

(Editor’s Note: In this week’s Thursday Feature, we take a look at the emerging technology that is improving the way forklifts detect and respond to potential backup collisions.)

Despite standardized training and safety procedures, there are still more than 100,000 forklift accidents in the US every year, according to the US Occupational Safety and Health Administration.

When you consider that there are only about 855,900 forklifts in use in this country, that’s nearly one accident per year for every 8.5 vehicles.

The most common type of forklift accident is striking a pedestrian, accounting for about 80% of all life truck accidents. Not surprisingly, these are the type of collisions that cause injuries — about 94,750 per year.

Underlying Causes of Forklift/Pedestrian Collisions

OSHA regulations require forklifts to be operated in reverse if the “load being carried obstructs forward view”. Even though most operators are trained to always look in the direction of travel, this is not always the case.

Another problem is that most forklifts are designed so that driver controls are located on the fork side of the vehicle, with the seats facing in the same direction. This can make it ergonomically uncomfortable for operators to twist in their seat so they can watch in the direction of travel when reversing.

While backup mirrors can help, there’s yet to be a mirror invented that can eliminate 100% of the blind spots. And it’s even worse in forklifts with enclosed cabins.

Compounding the issue is the trend toward warehouses with high-density storage, which means narrower aisles, less space to turn around, and more blind corners.

Backup Technology

All of these factors have contributed to a trend toward installing backup alarms on forklifts. These devised are designed to notify operators when any sort of obstacle is behind them.

There are two basic types of backup sensors:

Passive Systems

Passive backup sensors typically use cameras that are mounted behind the driver’s cabin. Images transmitted to monitors on the dashboard allow operators to see what is behind them without having to physically twist around. Disadvantages of backup cameras include the fact that they can be affected by temperature, dim lighting, and environmental factors such as dust and debris.

Another type of passive backup system projects a highly focused beam of light or laser from the vehicle onto the floor behind the forklift for the purpose of alerting pedestrians that a forklift is approaching.

Yet another type of passive backup system uses a beeping alarm that is automatically activated anytime the vehicle is put into reverse gear. Like the light beam, the purpose is to notify pedestrians of the forklift’s presence.

While beneficial, all three passive systems have disadvantages. Backup cameras can be affected by temperature, dim lighting, and environmental factors such as dust and debris. Light beams can be blocked by any obstacle, such as walls or shelving. And given how common they are, many pedestrians tend to ignore backup alarms.

Active Systems

New forklifts feature more active backup systems, including wearable active warning systems that require all pedestrians to wear a “tag” containing an RFID device. Whenever an onboard reader detects one of these tags, an alarm is triggered.

A more futuristic active backup system uses laser scanners that continuously monitor the area behind a forklift looking out for obstacles. When the laser detects any type of surface, the light is reflected back into a scanner and an alarm is activated.

Computers can then determine the distance of the obstacle from the forklift and can emit an audible alarm that can be adjusted based on proximity: One warning alerts drivers they are approaching an obstacle while a second warns that a collision is imminent.

Warnings  can include flashing lights, horns, buzzers, alarms, chime, or a combination of these. Laser scanners also can be connected to the forklift’s braking mechanism, causing the forklift to slow down or stop when an obstacle is detected.

Benefits of Laser Scanners

Laser scanners take the possibility of human error out of the equation. They operate automatically, regardless of whether the driver is paying attention, fatigued, or careless.

They also work regardless of ambient light, reflective surfaces, environmental conditions, and temperature.

When it comes to avoiding obstacles you can’t see, modern improvements to backup alarms may eventually reduce the number of injuries caused by forklifts accidentally backing into pedestrians.