Maybe being a father of a couple of young kids, one of whom is still riding in the rear facing infant car seat makes the recent stories of babies dying when they were accidentally left in the car all day when their parent (apparently most often their father) forgets to drop them at the day care in the morning worse, but it strikes me there ought to be something that technology can do to make this less likely. 

Low Tech Ideas

I read about the shoe trick the other day, and while it is clever, I don’t see it being foolproof. The one day you are rushing you will forget to place the shoe in the back too, and those are the most likely days you will forget the baby. Not to mention that it relies on you driving an automatic car. Those with a clutch pedal, will probably want to keep their left shoe on as well while driving.

Similar ideas exist using bags, or other items you are likely to remember, but realistically I think they all suffer from the same flaw, that they will be forgetten on the days when they are most needed.

I am also mystified why day care places don’t call to find out where their charges are when they don’t arrive on time and they haven’t been told not to expect them that day (I should actually check what my toddler’s preschool would do if he didn’t turn up and we hadn’t called to let them know).

Finally, for the low tech options, I read another suggestion that doesn’t rely on the day care place calling, but instead just has the parent who drops the kid off call (or I guess text if you prefer) their spouse to confirm the drop off. If the spouse doesn’t get the message at the expected time they can call to find out why.

A High Tech Idea

I have this little red low energy Bluetooth (BLE) device at home that is a demo/developer device for the Texas Instruments BLE chipset contained within it. This little gadget comes with a number of features that would be useful for building a baby seat alarm.

The basic idea is simple:

The device beacons continually indicating whether or not it detects a baby in the car seat. Any nearby BLE device can hear those beacons and will be able to react to them.

The parent either has an app on their BLE enabled smartphone (all recent iPhones and most, if not all, recent Android phones have support for this) that can listen for these beacons, or they have a complementary BLE gadget on their car keys that is paired with the baby sensor.

Now the clever part. One feature of the BLE spec is the ability to determine the approximate distance between the two devices. If the parent unit (app or key fob), detects the distance between it and the beaconing car seat increasing while the seat is occupied it can sound the alarm. Immediately reminding the parent that the child is still in the car seat.

Sensing the Child

There are baby seat alarms already on the market, but a study by the National Highway Traffic Safety Administration in July 2012 found none were that reliable. The devices in the study that sensed the child were mostly based on either a pressure pad under the car seat cushion, or a replacement chest clip for the car seat’s restraint. One was using carbon dioxide sensors integrated into the car to sense a breathing baby (or animal) left in the vehicle.

The pressure pads all suffer from being able to move, or having the child move off of them by shifting in the seat. The clips seem like they should be better but in the NHTSA testing seemed to have problems staying synchronized with the parent module. Also, as the report indicates, not all the deaths are from children in car seats. Some are from children who climb into the car themselves to play and then get stuck inside.

The TI Sensortag contains an array of sensors, most of which are irrelevant for this application (barometer, gyroscope etc). But, there is an IR temperature sensor behind that opening in the front of the device which functions a bit like the IR motion sensors username alarm applications. If the sensor is positioned where it can “see” the child, the IR sensor should be usable to indicate the presence of the child in the seat. The parent app can then arm itself and alert when it moves too far from the seat sensor.

Just an idea, and clearly it needs a little more experimentation and even a prototype. And then I think it would make an awesome Kickstarter/IndieGoGo crowd funded project.

An Alternative

If the IR sensor proves to be too difficult to make reliable, there is perhaps a simpler option: a tag bracelet that the baby wears and another that stays in the car. When the phone sees both tags, it arms. When the baby is dropped off, there will be a period of time when it sees just the baby tag, and then just the car tag again. If it starts moving away from the car tag and the baby tag at the same time, it can sound the alarm.

To avoid forgetting the baby tag, the app can also alert the user when it sees the car tag and not the baby tag; forcing the parent to confirm that the baby is not in the car for this trip before they set off.