The National Highway Traffic Safety Administration (NHTSA) reported that around 40,000 people died in vehicle accidents in 2023. Many of these accidents are due to blind spots. This staggering figure highlights the critical need for advanced safety technologies in today's vehicles.
One such innovation, the Blind Spot Monitor (BSM), has emerged as a game-changer in preventing these potentially dangerous incidents. In this guide, we will cover the essential details you need to know about the blind spot monitoring system and why your vehicle needs it.
What Does BSM Mean On a Car?
A blind spot monitoring system serves as an extra set of eyes for drivers. It monitors those hard-to-see areas around the vehicle that traditional mirrors can't capture.
Through a blind spot sensor and cameras, these systems can detect when another vehicle, person, or obstacle enters a blind spot. The driver is then promptly alerted through visual cues, audible warnings, or subtle vibrations.
This real-time information proves invaluable during lane changes, merging, or navigating busy highways. It significantly reduces the risk of collisions and enhances overall road safety.
Essential Components of a BSM System
A typical blind spot monitor (BSM) incorporates several vital components that work together to identify potential hazards and alert the driver:
Sensors
A blind spot monitoring system typically uses a radar-based blind spot sensor positioned on the vehicle's rear bumper, sides, or side mirrors. These devices continually monitor adjacent lanes for approaching vehicles that might enter the driver's blind spot.
Some systems use ultrasonic blind spot detection for nearby objects. This detection is delivered through a sensor commonly located near the rear of the vehicle.
Cameras
More sophisticated systems may incorporate cameras for visual blind-spot surveillance. These cameras are typically installed on the side mirrors or rear of the vehicle. They provide a real-time video feed that can be displayed on the car's infotainment screen.
Indicators
The most prevalent alert in a blind spot monitor is a visual cue, often manifested as a small symbol or light on the side mirrors. This indicator illuminates or flashes when an object is detected, remaining active until the blind spot is clear.
Certain systems include an additional audio alert (such as a distinct tone) if the driver attempts to change lanes while an object is detected in the blind spot.
Types of BSM Systems
A blind spot monitoring system can be classified into two major categories:
Blind Spot Warning System
This system is the most prevalent type of blind spot monitor technology. It is designed to alert drivers to potential hazards in their blind spots through visual cues. These systems generally rely on a radar blind spot sensor positioned at the rear of the vehicle.
An enhanced version of this type of blind spot monitoring system incorporates an additional audio alert feature. This additional feature provides an extra layer of safety during lane change maneuvers.
Automatic Emergency Steering System
As its name implies, this system not only warns the driver but also takes corrective action if necessary. If the driver attempts to merge into a lane where a vehicle is present in the blind spot, the blind spot detection activates. The system will automatically apply brakes.
It will also provide steering input to guide the vehicle back to its original lane. Simultaneously, it issues visual and/or auditory alerts to notify the driver of the potential collision risk.
There are versions of this system that incorporate scanners to identify vehicles approaching from the side during reverse maneuvers. This feature is particularly useful in parking lots.
How Does Blind Spot Monitoring Work?
In certain vehicles, the blind spot monitoring system activates automatically once you exceed a specific speed threshold. To indicate that the system is operational, a warning light briefly illuminates both exterior rearview mirrors or window frames. This indicator remains active while the transmission is in DRIVE or NEUTRAL.
Drivers typically have the option to deactivate the system if desired. Some vehicle models require manual activation or deactivation of the BSM system via a dedicated button.
BSM Technology and Detection Process
As mentioned earlier, the majority of blind spot monitoring systems use a radar blind spot sensor, although some employ camera-based technology. The sensor is typically positioned beneath the rear bumper or integrated into the side view mirrors. Their primary function is to monitor the areas adjacent to and behind your vehicle.
The blind spot detection zone generally covers approximately one lane width on either side of your vehicle. The coverage extends from the side view mirrors to roughly 10 feet beyond the rear bumper. This coverage allows the blind spot monitor to identify vehicles approaching your blind spots from the sides, rear, and front.
When a vehicle is detected within these zones, a visual alert—usually a yellow or red light—shows on the corresponding side mirror or window frame. The visual alert may also come with an alarm sound.
In high-end models, the steering wheel or driver's seat may vibrate to warn the driver. This vibration offers a physical alert that complements visual and auditory cues.
Limitations of BSM Systems
BSM systems are primarily designed to detect larger vehicles and may not consistently identify smaller objects, such as motorcycles or bicycles. For example, when a motorcycle enters your blind spot, the BSM indicator may not activate if the blind spot sensor fails to detect its presence due to its smaller size.
Hence, you must not rely solely on the system. You must also stay vigilant when changing lanes or maneuvering in traffic.
Benefits of Blind Spot Monitoring System
Blind spot monitor technology has greatly improved vehicle safety today. BMS systems have provided drivers with an invaluable tool to navigate roads more securely.
Let's explore some of the benefits you can get if you install a BMS system on your vehicle:
Prevent Side-Impact Collisions
A blind spot monitor plays a critical role in preventing side-impact accidents (T-Bone), which often occur during lane changes. BSM systems provide timely warnings to drivers. These warnings allow drivers to abort potentially dangerous maneuvers.
One research indicates that commercial vehicles equipped with BSM systems experience fewer side-impact collisions, particularly in urban environments like highways and bustling city streets.
Boosts Driver Confidence and Situational Awareness
With BSM systems, drivers feel more at ease knowing they have an extra layer of protection during lane changes and merges. This benefit is especially helpful for less experienced drivers in challenging traffic scenarios.
Navigate Dense Traffic Safely
In congested conditions, where visibility is often compromised, BSM systems act as an additional set of eyes. It keeps watch of vehicles that may be difficult to spot in heavy traffic.
The system also helps drivers navigate through tight spaces more confidently, which reduces the risk of collisions in stop-and-go traffic.
Choosing a Vehicle with a Blind Spot Monitor
When you choose a vehicle, consider one with a blind spot monitoring system for enhanced safety and driver awareness. An effective BSM system should include the following features:
- Accurate blind spot sensor
- Variety of alerts (visual, audible, and vibrations)
- Integration with other safety features
- A wide coverage area
You must also keep in mind that the cost of BSM systems varies depending on the vehicle type. In entry-level vehicles, it's often an optional feature costing around $500-$1,500, while in mid-range and premium vehicles, it may cost $1,000-$3,000. Luxury vehicles typically include BSM as part of their overall safety suite.
Make sure that you choose the BSM system that fits your budget. As much as possible, don’t be a miser if you can afford a better system.
A blind spot monitor is a critical safety feature that vehicles should have. This system offers enhanced safety during lane changes and merges. Hence, despite the additional cost, you should invest in one to give you more confidence and peace of mind.
