Bashful Clock Displays the Wrong Time When a Person Looks at It

Humans have a strong tendency to anthropomorphize the things around us, including lifeless appliances and devices. We see faces everywhere and like to assign human emotions to objects that don't even have brains. This tendency is so strong that we build artificial emotion into our devices so they feel more human and are more comfortable to interact with. That usually applies to robots, toys, and virtual assistants, but Guy Dupont took it further. He built a bashful clock that will display the wrong time whenever it detects a person looking at it.

When nobody is around, this is just a standard digital clock. It shows the correct time on a four-digit, seven-segment display. But if it notices someone looking in its direction, it displays an incorrect time — either out of malice or because it is flustered (you can assign whatever emotions you want, because it doesn't have any).

Just a few years ago, the hardware to enable this behavior would have been big and expensive. Sure, you could use a simple passive infrared sensor (PIR) to detect the presence of a body, but that would trigger when a cat passes by or when a person has their back turned towards the device. To make this clock act in the intended manner, Dupont needed face-detection. Fortunately, the hardware to detect faces is now very affordable and compact.

For this project, Dupont used the Person Sensor from Useful Sensors. This is a really cool piece of hardware, because it is a small self-contained module that contains both a camera and microcontroller with onboard computer vision capable of face detection. It sends relevant information, like the number of faces it sees and their positions in the frame, out via I2C.

Dupont's clock uses an Adafruit QT Py ESP32-S2 development board to monitor the data coming from the Person Sensor. Under normal conditions, it will show the network time on the display. But when the Person Sensor tells it that a person's face is within the camera frame, it will show a random time on the display. A simple 3D-printed stand holds the Person Sensor and display.

The "Clock That Is Wrong" doesn't have any practical purpose, but it is a really fun exploration of human emotion in a simple, everyday device. It also demonstrates how inexpensive and easy it is to incorporate face detection in a project.