Child Safety Seat Cooling System, a Reflection

My Experience

It is easy to lose sight of things when you have so much on your mind, parents who forget their children in the car are victims of their own conscious. This topic is truly disheartening, imagining the pain that families must endure and the guilt that lies on the shoulders of the parent is indescribable. In my own experience, I do not have any children, but I was once a child. I can remember one time when my mother and I made a trip to the grocery store, and she forgot to bring me in with her. Luckily, I was not so young that I could not get out of the car myself, but I still remember how quickly the vehicle became unbearably hot. I got out of the car, the alarm was going off because I opened it from the inside after it was locked, and I was sweating head to toe. It felt like ages until my mom came back out from the store, surely if I had been younger and constrained to a child seat it would have been a death sentence. She thought I was with her the whole time she was in the store, and it was hard to comprehend how you could forget something so important like your child, but no one is infallible. This paper investigates the necessary integration of safety features into child seats that increase the chance of survivability in the event that a child is left behind in the vehicle [1]. I believe that this paper has strong moral and ethical justification along with engineering rigor and justification for the system being designed.

Purpose and Expectations

I believe that the purpose of this report is to provide a solution to the critical automotive safety issue that is the injury and death of infants and young children who are left alone in parked vehicles during summer months. The temperature difference between the ambient and the inside of the vehicle grows quickly, and the idea is to reduce the localized cabin air temperatures for a longer period of time by designing a child seat with an integrated cooling system. My expectations from the paper are to learn about the design of the system, understand the methods for how the system was analyzed and then see results from a prototype experiment.

Reflections

In the introduction the problem is identified, and a solution is described concisely. I think that the use of thermoelectric cooling system idea is an excellent solution given that all it required is power from the vehicle battery. A heat exchanger could generate a higher temperature difference in the cooled air being supplied to the seat, however it would require extensive modifications to the vehicle. Since most modern vehicles have an electric water pump and electric fans attached to the radiator a separate cooling circuit could be used to provide cooler air to the child seat, increasing the longevity of survivability. A schematic of a proposed solution that integrates the vehicles cooling circuit and radiator system is shown in figure 1. The idea is to use electronic 3 way valves to isolate the engine from the circuit, and use the radiator to lower the temperature of the coolant going to the external heat exchanger which is lowering the temperature of the air in the vehicle using ducts and a fan.

Figure 1. Proposed solution that has the potential for a greater cooling power.

There are still many benefits to using thermoelectric as the paper discusses, such as the reliability and compact nature of the devices. For this application, they are required to cool only the zone around the occupant of the child seat, so there is a lower required amount of heat to be removed through convention. The inclusion of the alarms into the system is a great idea, the primary goal of this seat is to alert parents to the presence of the child in the seat, and if that fails then the seat can provide a high rate of survivability with the cooling system. Modeling the system in Matlab/Simulink in order to come up with a theoretical response of the thermal system is an excellent tool for understanding the trajectory of the states depending on the initial conditions of the system. The physical experimental setup is a very ingenious and relatively inexpensive. I think that it is interesting how the heat generated from the infant was represented by using a submersible resistance heater. Performing validation tests results in the paper provides solid evidence for the experimental setup. Variations in the intake and exhaust locations for the heat exchanger as well as the different child heat models helped create a useful comparison. The design of this experiment was well thought out. I think that the paper presented the results in a well organized manner, both the transient measurements and key takeaways are present. I cannot imagine the pain that a child must endure over 90 minutes trapped in a hot car, that’s a terrible demise.

Next Steps Moving Forward

The paper recommends that greater amounts of heat rejection from more TECs or other supplemental cooling methods should be investigated to extend the survivability time, ideally to infinity. The big problem here however is preventing these actions before they occur, which is why societal education is extremely valuable and should be sought after. Automotive manufacturers should provide options to families owning a child seat to have a system integrated that can provide the lifesaving and alerting features. Otherwise 3rd party companies would need to come up with a modular design that can be easily integrated into any vehicle.

Conclusion

I thought that this paper thoroughly explored the subject matter and presented the supporting evidence in a way that made understanding the end results quite easy for the reader. I hope that this research continues to grow and that there are fewer young lives lost because of the farsightedness of parents in todays society.

References

[1] J. W. Finn, J. R. Wagner, E. J. Walters and K. E. Alexander, “An Integrated Child Safety Seat Cooling System—Model and Test,” in IEEE Transactions on Vehicular Technology, vol. 61, no. 5, pp. 1999-2007, Jun 2012, doi: 10.1109/TVT.2012.2191427.