A year ago, on February 13, we introduced the Pod, the first bed in the world that uses advanced cooling and heating technology to help you fall asleep faster and stay asleep.
Today we reflect on how the Pod has changed what we expect from our mattress and what it means for the future of sleep.
The idea
The idea for the Pod came from our own customers, going as far back as January 2015. When we launched our very first product – an accessory cover to track your sleep without wearables, we asked our earliest customers what they wanted to see next from us. The number one request by far was a cooling solution. Sleeping hot wasn’t an issue for any of us as founders, but the data from our members and the scientific research didn’t lie: sleeping hot is the top issue for sleep.
We dove right into the research of temperature and sleep and came up with a solution to use technology to not only cool you down but also keep your bed cool and, most importantly, adjust the temperature automatically based on your individual biometrics.
The science
Our body temperature regulates between 96.8 and 100.4 degrees Fahrenheit over each 24-hour cycle. This aligns with each individual human circadian rhythm. We naturally fall asleep when our internal body temperature drops, and body heat loss is at its highest. How you feel though is actually opposite to what is happening inside your body core: as your body temperature decreases, you feel warmer, and as your body temperature increases, you give off heat, making you feel colder (similar to a fever.)
Cooler body temperature is by nature associated with sleep while warmer body temperature is energizing.
Because temperature is so crucial to help you fall asleep and stay asleep, it’s particularly important to control it in real-time as it fluctuates during the night. But until one year ago, there was no solution that could perfectly balance your bed’s temperature based on what your body needs.
Traditionally, mattresses absorb the heat that our body dissipates, causing us to overheat during the night. Foam mattresses, while most comfortable, trap the most heat, and mattresses with “cooling” gel start off cool but they eventually absorb the surrounding heat.
Because these mattresses can’t adapt to the fluctuating temperatures that our bodies go through while asleep, we end up waking up in the middle of the night feeling too hot or too cold.
Our solution
The Pod is the first mattress with the ability to heat or cool each side of the bed to your preferences, with temperatures ranging between 55 and 110°F. So it is comfortable to use in the winter or the summer. The Pod senses your sleep patterns and automatically adjusts the temperature to help you fall asleep faster and keep you asleep.
An exploded view of the Pod
The Pod is a system made of multiple components:
- The Mattress is made of four layers of CertiPur-certified foam for the ideal medium firmness and contouring support. It’s encased with our proprietary Active Grid cover.
- The Active Grid is a thin, malleable and perforated layer with water channels. It regulates the temperature on each side of the bed individually to ensure the perfect sleep environment, easily programmed and totally customizable.
- The Hub sits right next to the bed and is home to the Pod’s proprietary thermal engine. Water flows from the Hub to the Active Grid to keep temperatures as warm or cool as users desire. This technology is the foundation of Pod’s most groundbreaking feature, dynamic temperature. The feature includes AI that learns sleep habits to adjust bed temperature automatically.
- The Eight Sleep App, available for iOS and Android, lets you control the settings and access the reports and insights on your sleep. You can use the app remotely, and get your Pod temperature going from anywhere in the world.
How we built it
It took us a few years to get to the position where we could invest in the right team and the right resources to develop a product that offered a real solution. We began working on the Pod back in 2018 – under the codename “Frozen”. Frozen was such a popular name in the office that we even considered giving the product that public name, but after a close trademark inspection we decided we didn’t want to get into any legal troubles with Disney.
For a little over 18 months, we prototyped many cooling solutions that could be integrated with the mattress. We set parameters early on for what the design had to achieve: (1) it had to be comfortable, (2) it had to be quiet, and (3) it had to cool down to the lowest possible temperature — and stay cool. We quickly realized that this wasn’t an easy design challenge: you can cool down to frigid temperatures, but not without compromising on the noise or comfort. The answer lied right at the intersection of these three metrics.
Hardware prototypes, June 2018
Design decisions, October 2018
Perhaps the most significant challenge we faced was on the data side. How do you build an intelligent product that uses a sensor technology for which very little to no public data exists? This lack of understanding between the relationship of temperature and sleep meant it was up to us to learn from scratch.
We leveraged learnings from our first generation of products and set out to gather a larger amount of truth data so we could train our new algorithms. We began a repetitive process of collecting small amounts of biometric data from a variety of sources including self-reporting, consumer-grade devices, and medical-grade devices. We used this data to train our neural networks to learn how to identify sleep, sleep phases, heart rate, respiratory rate, tosses and turns, and more, out of a set of raw data. As we found scalable ways of gathering that ground truth data, our training process moved at an even faster speed, and we were able to make significant improvements over time. We continue to make