Tech Today

WORDS BY DAVE MACKINNON

As we continue to look at different collision avoidance systems, our path brings us to parking sensor systems. First introduced to the automotive industry in 1982 on the Toyota Corona, these compact and inconspicuous devices provide drivers with clear warnings that an object or person is in the path of their vehicle. In terms of preventing back-over accidents while parking or maneuvering, parking sensors are considered one of the best solutions available.

A parking sensor uses low-power electromagnetic transmitters and receivers to detect objects. In most applications, an array of four sensors are integrated into the vehicle’s bumper to provide full coverage of one end of the car or truck. The sensors include an antenna that looks for reflections of the pulsed signal it transmitted. When an object is detected, the system can provide an alert to the vehicle operator. Because parking sensors work

similarly to radar, the system can also let the driver know the distance to its detected object.

Sensor placement is crucial to the reliable operation of the system. The distance between the sensors and their mounting angle plays a significant role in determining how well they cover the vehicle’s front or back. As with any aftermarket collision avoidance system, proper installation is crucial to the overall functionality.

Unlike a backup camera that requires the driver to remember to look at the screen, parking sensor systems are a fully active safety solution. When an object is detected in the sensor’s path, an audible alert is produced to warn of an impending impact. Even if the driver isn’t paying attention to what they are doing, the warning will let them know they need to react.

Most systems include a display that lets the driver know how close they are to an object. The systems will display the distance to the item on a small LCD seven-segment display. Warning bars will also provide an intuitive guide to let the driver know how close they are. While perfect for avoiding bicycles and toys, these systems are great for applications where the vehicle is backing into a parking space in a garage. Those that don’t include displays provide a series of beeps that increase in frequency as the vehicle approaches an object. Most switch to a steady warning tone when the obstacle is about 12 inches away.

Traditionally, parking sensor systems have been associated with installations on the rear of the vehicle. While these represent the majority of installations, there are many systems available that include additional sensors that can protect the front of the vehicle from damage. Knowing when the vehicle is inches from a wall or fence helps clients pull their car or truck far enough into a parking spot to ensure the other end isn’t sticking out into the roadway.

The Curb Alert PRO from Brandmotion is a very popular upgrade for people with lowered and exotic vehicles. This system uses an infrared-based distance sensing system that designed specifically to alert the vehicle operator when he or she is approaching a curb or parking stop. In many cases, the front of these vehicles would contact the curb before the front tires of a vehicle, resulting in significant damage. Once installed, your team can calibrate the system to provide an audible warning at a distance between eight and 28 inches from an object. This product is a great solution to market to local enthusiast groups, car clubs and high-end vehicle dealerships.

The best way to demonstrate how a parking sensor system works is to have one installed in a shop vehicle. You can invite the client to sit in the car or truck with you, the reverse toward a wall or another vehicle to show them how the warnings work. It’s important to highlight that the system doesn’t require any intervention from the driver to make it work. There are no buttons to push or switches to enable. Everything is automatic.

If you don’t have a vehicle that’s always available, the next best option is to have a system on display in the store. You can use two or four sensors installed on a wall-mounted display. When you enable the system, you can walk toward the sensors to demonstrate how they work. If you happen to sell truck accessories, integrating the sensors into a tonneau cover or upgraded rear bumper display is a great idea. Add some small cards with arrows pointing to the sensors to get clients asking about them.

Each manufacturer has specific guidelines about where and how to install its parking sensors. In most cases, the sensors need to be spaced evenly across the bumper. They also need to be mounted so that the sensor’s face is vertical or pointed upward at a few degrees. If they are pointed down, the system may produce false alarms. The sensors need to be a specific distance above the ground, often 18 to 30 inches, depending on the brand.

Before one of your technicians starts drilling into a metal bumper, make sure the system you are installing has plastic or rubber grommets that are compatible with this type of application. Not all include these pieces. For those installing in a plastic front or rear bumper cover, make sure that any metal safety structure behind the plastic won’t prevent the sensors from being installed. Likewise, don’t drill into a front or rear impact bar to provide clearance. Even minor alterations can dramatically reduce the effectiveness of these items in an accident.

If your client wants this feature, most parking sensors can be painted to match the paint on a bumper. As these are high-frequency devices, there are limitations to the thickness of the paint and the finish. The paint on all the sensors should be the same thickness, so painting them all at once is recommended.

Most sensors allow for coatings up to 125 micrometers, including base and clear coats. The painter should be advised that they’ll be painting plastic and aluminum surfaces, as this may alter the primer they use. Finally, there are often specific guidelines about avoiding getting paint into certain parts of the sensor. These areas are often referred to as an air-gap. Check the specific instructions for the sensors you are installing before you begin the painting process.

As a professional mobile enhancement retailer, you should already have extensive knowledge of how to run wiring safely and securely. As the wiring for these sensors is relatively small, you’ll want to be gentle with it and not damage the connectors or pull the wires out of the sensors. Your technicians will want to run the wires away from electrical interference sources like computer modules or high-current loads.

If connections need to be made outside the vehicle, make sure everything is weathertight. Adhesive-lined heat-shrink tubing is a great way to seal connections to keep water and debris away from the terminals. You can also apply a small amount of dielectric grease to weather-resistant terminals for an added layer of protection. Dielectric grease, sometimes called anti-corrosion gel, is available from Install Bay and auto parts stores. Design

Engineering Inc. and Wurth offer self-vulcanizing rubber tape that bonds to itself. When wrapped tightly around connectors, it will help to prevent water from infiltrating the connection. This tape is also an excellent solution for backup camera installations in pickup trucks where connections need to be made under the bed.

If you have a parking sensor solution that works with metal bumpers, consider treating the drilled hole edges with a corrosion-resistant coating. Cold-galvanizing paints and compounds are a great solution to prevent salts and chemicals from damaging chrome finishes around the sensor openings. These coatings can be sprayed on or applied with a brush, and most are dry in 20 to 30 minutes. Your technicians can continue working on the interior of the vehicle while the paint is drying.

Once your team is adept at installing parking sensors, you’ll find that they’re a profitable solution. If you’d like to bring more customers interested in this sort of solution to your facility, be sure to apply to the Vision Zero website to have your store listed as a Preferred Retailer. Visit www.vzan.org for more information.

Dave MacKinnon has worked in the mobile electronics industry since 1988 in almost every capacity, including roles as a Retail Salesperson, Installer, Sales Representative, Technical Trainer and Product Development Manager for some of the largest car audio companies in the world. Dave started his writing career in 2000 as the Technical Editor of a Toronto-based car audio magazine and has reviewed more than 450 products. Formally trained as an Electronics Technician, Dave is considered an industry expert when it comes to explaining how mobile audio components work, and he has crafted thousands of articles to share that knowledge. He’s currently the Head Writer for 1sixty8 media and the Editorin-Chief at BestCarAudio.com.