Your Next Weekend Project: A Fully Offline, Voice-Activated Robot Dog
Build your own offline, voice-controlled robot dog with an ESP32-S3, and learn a lot about robotics and 3D printing in the process.
There are plenty of good reasons to build a robot in your free time. For instance, you can learn a lot in the process and pick up some new skills that might come in handy in future projects. It is also a lot of fun, and the robot you build can keep you entertained for years to come.
If you’re looking for a good place to start, then you should definitely consider building Tech Talkies' little robot dog called Jolly. It is made from accessible and inexpensive hardware, and the build process is very simple. But despite the simplicity, Jolly has some really interesting features. It can respond to voice commands, for example, without accessing any cloud-based services — everything runs completely on-device.
The robot is designed around the Seeed Studio XIAO ESP32S3 Sense, a compact and powerful microcontroller that doubles as both the brain and ears of the robot. Thanks to an onboard digital microphone, the system is capable of detecting and processing voice commands locally. This offline capability offers both faster response times and improved privacy.
The robot’s movement is driven by four micro servo motors, each assigned to a specific leg. These servos enable Jolly to perform a wide range of actions, from walking forward to sitting down and dancing. Careful attention is required during assembly, especially when positioning the servos. The builder emphasizes orienting all servo wires outward to prevent tangling or pinching once the chassis is fully assembled.
Power is supplied by a 1,000 mAh LiPo battery, paired with a combined charging and boost module. This setup ensures the robot receives a steady 5V supply while also allowing for convenient USB charging. To keep the internal layout clean and reliable, all components are mounted on a prototyping board, reducing the complexity often associated with wiring.
The mechanical structure of Jolly is built from 3D-printed parts, forming a lightweight yet sturdy frame. Small but thoughtful design choices — such as adding strips of electrical tape to the feet — significantly improve traction on smooth surfaces, enhancing overall mobility.
Once assembled and programmed, Jolly responds to a wake phrase — “Hi Jolly” — before executing commands like “come here,” “sit down,” or “dance.” If you'd like to build your own compact, expressive robot dog, take a look at the GitHub repository for the circuit diagram, 3D design files, and firmware.