Image Credit: shutterstock.com/chombosan
It is estimated that approximately 3% of all new vehicles that leave the factory will have some type of leak within their interior that is capable of causing detrimental effects such as mold growth and damage to the electronic components, which can eventually greatly decrease the value of these automobiles and their respective producing companies1.
While this may not seem like a large percentage at first, over the last three years, about 500,000 vehicles were recalled as a result of leak-related warranty claims.
While the automotive industry employs a variety of leak testing processes to maintain the integrity of their products, small leaks are often left unnoticed until the vehicle is already purchased. In addition, typical materials that cars are comprised of such as aluminum, glues, composites and hundreds of various electronic sub-assemblies further increase their susceptibility to water damage.
A traditional manual method used to detect leaks that are present in a vehicle during its production is the “soak test.2” During this method, vehicles are sprayed with multiple angled water jets whose pressures can be as measure to be as 2,00 psi. Once the water jets are applied to the vehicle, industry workers inspect the vehicle visually and manually to detect whether any water fell into the vehicle during the test.
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While useful for large leaks, the soak test often leaves smaller leaks that are often present in inaccessible areas to continue to go unnoticed. By missing such leaks, water is able to easily pool in these areas, thereby further progressing its ability to induce damage to these areas of the vehicle. INFICON, an international electronic equipment and instrumentation company, is one of the leading producers of leak detectors worldwide2.
With its applications for leaks that are not only present in vehicles, but also in refrigerators, air conditioners, semiconductor components and solar technology products, INFICON is known to provide high quality tools to ensure their maintenance. Its testing mechanisms can employ either vacuum leak detection, accumulation leak detection or sniffer leak detection to measure the leak rates present in its applied products3.
While useful in their detection capabilities, such devices are not completely practical as they are very large in their design and require some expertise in their operation.
In their collaborative effort to develop a two-fold in-line vehicle production leak detection solution, ON Semiconductor and RFMicron have developed the RFM5126 Moisture Intrusion Detection System1.
The first part of this system is comprised of thin and unobtrusive moisture sensors that are placed in areas within the vehicle where water can pool and often go unnoticed to the naked eye. The second part of this system is used to read and analyzed data collected from the sensors to determine the exact location of the leaks.
In addition to their high specificity, the sensors present within the RFM5126 system are battery-free and wireless. To enable the sensing technologies, vehicles are driven through a series of portals that have mounted antennas to wirelessly communicate with the sensors present on the vehicle’s metal chassis.
The traditional high-pressure soak test is subjected to the vehicles both before and after they are scanned through the portals, which allows the sensors to determine the change in moisture from both time points2. The specific data that is provided by the sensors to the automotive worker includes:
- The wet and/or dry status of the vehicle
- The location of any leaks
- Chassis and trim style statistics
- Assembly plan statistics
- Specific insights into the affected materials/components
By having the precise details on where the leaks are, automotive industrial workers are able to repair these leaks in a fast and efficient manner prior to their delivery to the public. In addition to benefitting the consumer, the RFM5126 system reduces repair costs, as well as reducing time for the manufacturer to blindly search for the possible cause of damage to the vehicle2.
- “Battery-Free, Wireless Sensor Technology Detects Water leaks During Vehicle Production” – Business Wire
- “Moisture Intrusion Detection System” – Semiconductor Components Industries
- “Leak Detectors” – INFICON, Accessed: May 2017