Dancing arms give faceless clock the edge
We've seen a number of frankly bizarre time-keepers over the years, including a watch that uses famous landmarks to show time zones, a clock that makes you solve math problems and another that displays the time as shadows when someone touches its face. Architect and hobby tinkerer Ekaggrat Singh Kalsi joins that strange clock party with the Edgytokei, where dancing mechanical arms show hand positions on a clock face ... except there's no clock face.
Ekaggrat Singh Kalsi says that Edgytokei translates to "edge clock," an apt description, and was inspired by nunchaku – traditional martial arts weapons made up of two wooden sticks joined together by a short chain or rope.
Time on an imaginary clock face is displayed by the mechanism's two arms that reach up and out from the base. Actually telling the time takes a bit of effort but as you can see in the video below, the way the arms get to the time they display at any given point is absolutely mesmerizing.
The center of the arms changes depending on the time being displayed, the fulcrum could be in the middle of the base or to the left or right of the clock's invisible face. Each arm features LEDs that change color to show which arm represents the hour hand and which the minute hand, and both arms are equal in length.
The lower arm is driven by a geared stepper motor and can slide on along and lift up to raise the two arms above the base. The upper arm has another stepper motor at its elbow. Power is fed to the second stepper via copper tracks on the outside of the arms and brushes on the base.
An Arduino Nano development board provides the brains of the operation, which keeps time and controls the motors. And so that the clock knows where its home or 12 o'clock starting point is at power on, an IR sensor looks for different colored strips on the lower arm. One value tells it to move left to return home, and the other to move right.
Finally, just in case the Edgytokei doesn't seem cool or clever enough, all of the components that make up the clock's structure were 3D-printed.
Project details, files and a component list are available via the source link below. And Ekaggrat Singh Kalsi has even hinted that a kit version of the build may be released at some point in the future.
Source: Ekaggrat Singh Kalsi/Hackaday