Fans of the long-running and ever-fantastic British TV show Dr. Who will no doubt hold a soft spot in their hearts for the Doctor’s little robot companion. No, not one of his many human sidekicks, we’re talking about K-9, the angular dog-like android that burst onto British screens back in 1977.
There were a number of original [K-9] props made by the BBC, and these were eventually sold by the corporation. One found its way to Abertay University, and it was there that [Gary Taylor], a computer science student found it. Sadly the years had not been kind to the robotic mutt, in particular water from a roof leak had damaged its internals beyond repair. With little more than the fibreglass shell to work with, he set out to rebuild K-9 and make the task the subject of his dissertation.
The original robo-dog was little more than a 1970s remote-controlled car, but its upgrades bring it firmly into the 21st century. At its heart is the inevitable Raspberry Pi 3, coupled with an Arduino mega 2560 that handles motor control and interfacing to an array of ultrasonic sensors. The Pi’s Bluetooth radio talks to an app on an Android phone, that serves as the K-9’s controller. All of which makes for an impressive upgrade, but we hope has disturbed as little of the original prop work as possible
Not everyone is lucky enough to find an original K-9, but for those destined for classic BBC prop disappointment there is always the possibility that you could build your own.
[James West] has a young Doctor Who fan in the house and wanted to build something that could be played with without worrying about it being bumped and scratched. So, instead of creating a replica, [James] built a simple remote controlled K9 toy for his young fan.
K9 was a companion of the fourth Doctor (played by Tom Baker) in the classic Doctor Who series. He also appeared in several spin-offs. A robotic dog with the infinite knowledge of the TARDIS at hand, as well as a laser, K9 became a favorite among Who fans, especially younger children. [James] wanted his version of K9 to be able to be controlled by a remote control and be able to play sounds from the TV show.
Using some hand-cut acrylic, [James] built K9’s body, then started on plans for the motion control and brains. [James] selected the Raspberry Pi Zero for the controller board, a Speaker pHat for the audio, a couple of motors to move K9 around, and a motor controller. K9 is controlled by a WiiMote and has a button on his back to start pairing with the WiiMote (K9 answers with “Affirmative” when the pairing is successful.) When it came to the head, [James] was a little overwhelmed by trying to make the head in acrylic, so he got some foam board and used that instead. A red LED in the head lights up through translucent red acrylic.
It’s a great little project and [James] has put the Python code up on Github for anyone interested. We’ve had a couple of robot dog projects on the site over the years, like this one and this one.
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