Peek at Your Presents Early with This Ornament-Shaped Spy Robot

Coming up with the concept

While the holidays are a time of giving gifts, people also love the moment when they reach under the tree to grab their presents and open them. But for those who want a sneak peak at what awaits them a little bit early, element14 Presents host Milos Rasic has designed and constructed a discreet robot that allows for remote viewing below the tree. His goal while building it was to have a robot that could blend in as an ornament, lower itself to the ground at night, and then drive around while simultaneously delivering a livestream to the operator over Wi-Fi.

Mechanical design

One of the most challenging aspects to the design was figuring out how to fit a control board, battery, several motors, and occasionally-exposed wheels into a spherical housing. The solution Rasic created was to mount the powered wheels onto continuous servo motors and lower them from a folded position with an additional wheel and servo. This way, similar to a plane's landing gear, they could remain neatly tucked into the chassis until it was time to drive. Repelling from and climbing back up the tree is accomplished through a piece of fishing line wound around a fourth servo motor.

The electronics

Controlling the robot is an Arduino Nicla Vision board since its small size, onboard camera module, and external GPIO pins made it a great fit. Because the servos and Nicla Vision run off 5V, Rasic included an LM317 voltage regulator to decrease the 9V battery's output to an acceptable range. Furthermore, he added a MOSFET for toggling the headlight LEDs and a transistor on each servo PWM input pin in order to protect the Nicla's GPIO pins from damage.

Streaming video with remote commands

Since the goal of this project was to remotely spy on the presents below the tree, having a usable camera feed was of utmost importance. Luckily, OpenMV had already published an example for creating a real-time streaming protocol (RTSP) video feed using their libraries, so it was as simple was setting up the camera and feeding its output into the network callback function.

Using the robot over Wi-Fi, however, required some extra setup due to the myriad of ways it could be implemented. Rasic opted for the MQTT protocol which let him configure the robot as a subscriber that could listen for his Node-RED application's published messages. Then, once decoded, each command is mapped to a motor or lighting action such as repelling, turning, or toggling the lights.

Spying on some gifts

As Rasic demonstrates at the end of his video, he was able to hide the robot as an ornament within the tree, lower it to the ground, and then briefly drive around- all while receiving a livestream of the presents that awaited him. To see how this project was built in more detail, you can watch his video below or visit the project post on element14.