Circa - An alarm clock designed to make you sleep better.

2 years

Robert Bronwasser Design
Grinn Global


This project in 60 seconds

More and more people use their smartphones to wake up in the morning. It enables you to set multiple alarms and it’s easy to use. The unfortunate side-effect however, is that people stay online longer at night, resulting in a loss of sleep.

The alternative, the traditional alarm clock hasn’t changed much over the past 50 years. It’s often hard to use, sounds unpleasant and doesn't consider your sleep when waking you up. Our question was therefore: Can we design a better alternative that supports people in improving their sleep?

Circa is a stand-alone alarm clock without distractions. The custom sleep sensor underneath the mattress detects your sleep stages and helps you to wake up more refreshed during light sleep. The white noise generator, music and breathing exercises help you to wind down before sleep. The project was co-funded with a crowdfunding campaign, raising over €150k in pre-sales. In 2018, Circa was awarded a Dutch Design Award in the product category.

My role

I was — among others — responsible for creating an overall vision of what Circa could be next to the bed. As an interaction designer, I worked together with an industrial designer and visual designer to create a seamless user experience between software and hardware. I worked on creating the product video and photos and the creation and promotion of the crowdfunding campaign.

Later on, I worked on research and development of the sleep sensor hardware and algorithms and development of the audio and user interface hardware. I worked together with developers, hardware engineers and manufacturers to implement Circa’s features through various iterations.


We started our research by identifying what factors improve your sleep, and where we thought technology could have an opportunity to intervene or help people.


We then proceeded to do short, informal interviews with people. We asked them what their issues were when trying to pick up or keep a healthy sleeping routine. We also asked general questions about their knowledge of sleep hygiene. Doing so, we identified a few key issues people have:

1Distractions in the bedroom that keep you awake, such as TV or your smartphone.

2Going to bed and waking up at the same time daily, especially in combination with a social life & weekends.

3Current ‘quantified self’ technology mainly tells you numbers, not what you can do with these numbers.

4Snoozing in the morning.

5Lack of general knowledge or misconceptions about secondary factors that influence sleep (such as alcohol, exercise and your diet).

Market Research

The market focussed on sleep-products is an active one at the moment. We analysed and tested a few products on their functionality, and at what point people interact with the device.

Research, Analysis & Synthesis


From our findings & research, we identified two main target audiences and their main goals and frustrations. Based on these audiences, we created two personas to use during the design process.

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Design Philosophy

During our research, we realised that our products main focus was on helping people sleep better. In this day and age, a lot of companies focus on getting your attention and collecting and selling data. We were inspired by principles of the Center of Humane Technology to design technology that is respectful towards the user and their information. During the early phases of the project, we developed the following philosophy to adhere to:

1No distractions
Our product helps people sleep. It should never distract them from their sleep.

2Privacy centred
Our product is living in the bedroom. It should therefore respect privacy.

3Design for regularity & rhythm
Regularity is the most important. The product should reflect this.

4Insights & educate
Too many products just give numbers. We want to provide people with ways to improve their sleep hands-on.

5Other functionalities

Key Features

Strengthened by the research phase of the project, we ended with useful insights and hundreds of possible features and a clear sense of direction:

Circa needs to be a beautifully designed standalone product without distractions that helps people maintain a healthy sleep routine. A few of the key features we identified:

1Setting alarms with freedom people are used to nowadays. This means repetition, multiple alarms for different days of the week, etc.

2 A sensor that detects people's sleep stages, to wake them at the right moment: during light sleep.

3 Technology that just works. Put the sensor underneath the mattress once and forget about it.

4Provide insights into sleeping habits and how to improve on them.

5Beautiful clock faces, displayed on an OLED display to limit the amount of light emitted by the device.

6High quality audio to wake people with nice sounds and music from their favourite radio stations and playlists.

7Easy to use interface, using physical controls for often used interactions and a touchscreen to input more complex information.

Industrial Design

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For the industrial design, we worked together with Dutch designer Robert Bronwasser. Our goal was to create a product that was unique yet modest, fitting within a variety of bedrooms. We worked with simple shapes, rounded corners and textiles, to create a friendly product that fits well within a living environment.

During this process, we worked together to create a seamless integration of physical and digital interaction. This is best shown in the rotary dial on the right of the clock, a visual metaphor to classic watches, as well as the ability to quickly navigate the user interface through physical interaction.

Interaction Design

Main system structure

From our list of features, we derived five main functionalities: Clocks, Alarm, Sleep, Music & Settings. The first four are functionalities that are used on a daily basis. They are accessible in the main menu next to the rotary encoder for quick access. To keep the touch areas in the main menu large enough, the settings menu is available from the top left of the home screen.

The different clock faces of Circa. Also the screen Circa returns to when idle.

Setting, changing and deleting alarms.

To gain sleep insights, as well as finding aids to fall asleep at night.

(Internet) radio, Spotify and other music sources.

Prototyping Interactions

To experience and validate interactions early on in the design process we created a laser-cut prototype with an Android phone and a Teensy microcontroller. The microcontroller is used to convert button and dial input into keyboard presses that are received by a web page running on the phone. This allowed us to hands-on experiment with different locations of the menu and finding the right animations to communicate hierarchy and affordances within the interface.

Levels of interaction

Core features like setting and muting alarms and changing the volume can be accessed using the rotary dial or the buttons on top of the device. The dial is also useful for navigating long lists of radio stations and Spotify playlists.

More complex features like scheduling alarms on specific days or entering your wifi password can be accessed using the touchscreen. Many features can be accessed using both the touchscreen and dials, this redundancy in interaction allows power users to speed up their workflow without compromising accessibility to the average consumer.

Improving touch precision

Circa features an OLED touchscreen that fades away beautifully in the faceplate of the device. When touching the screen or buttons the menu fades in next to the rotary dial. Having the menu next to the dial invites users to hold the dial while interacting with the menu, improving touch precision when users reach to the device from their bed.

Contextual Information

We identified that people often double-checked whether the alarm was set when turning off the lights at night. Circa detects this moment with the light sensor and shows a quick reminder when the next alarm will ring. Because of the backup battery, it will always wake you up, even if the power is down.

Visual Design

Circa uses an OLED display. In an OLED display, black pixels are turned off and therefore do not emit light. In a user interface, you often use shading to create a hierarchy and boundaries, helping users to focus their attention. But because our priority was on cutting down light pollution, we were restrained by using a completely black background. Instead, we're using font weights, text shading and accent colors to guide people through the interface.

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Research & Development

In a start-up, you're often wearing multiple hats. In addition, to design and project management, an important part of my job was focused on the development of the sleep sensor hardware and algorithms. I used academic research and worked with suppliers and manufacturers to find the right technologies and materials to develop the sleep sensor.

I proceeded by creating prototypes of the sensor hardware and software that is able to detect vital signs like respiration, heart rate and movement using a really sensitive pressure sensor underneath the mattress. In the video above you see the signal from the sensor, it's a combined signal that contains the heart rate, breathing, and any body movement. Using filtering we're able to get the individual signals out used for analysis.

I tested our hardware and algorithms in the bed at our office (the perks of working at a sleep hardware company) and did tests at night against reference technologies.

Together with hardware engineers and software engineers I worked on optimizing and developing the sleep sensor into its final form.

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I hope you enjoyed this project.

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