Count
Count is a timer for screen management that sets phones aside while giving people a way to track time spent on tasks. It is the flagship product of Out of Sight, a family of time-keeping devices that help people spend time on the moments that matter.
I handled all of the mechanical and electrical engineering alongside an industrial designer and design strategist for our year-long, master's capstone project. We placed second in Penn's 2018 iDesign Prize.
May 2018
Key Features
Phone Lift
After playing around with constant force springs and other passive ways to lower and lift the phone, I ultimately landed on using a stepper motor actuated rack and pinion. By leveraging the back drive resistance of the motor, I was able to create haptic dampening as the phone is inserted into Count.
That same stepper motor is then used to lift the phone out of the slot when time is up. For this, I wrote firmware to create a non-linear ease-in/ease-out motion to add to the "magic" moment as the phone reappears from the slot.
Dial Mechanism
The dial is fastened to a custom gear ring on the inside of the device, which turns an encoder to read the user's time input. One of the difficulties with designing the dial was that we wanted the dial to tick down after the time was set, similar to a kitchen timer. This was accomplished with another stepper motor that rotates the dial as time counts down and also acts as a damper when the dial is being turned to set the time.
Color Wheel
Once the phone is inserted and the time is set, the seemingly blank face on Count suddenly winds up with color. To create this effect, I designed a system of interlocking acrylic film, driven by another stepper motor, all of which sits inside of the dial behind a frosted acrylic window.
The blue, time-indicating film is mounted to the stepper motor, hidden behind the white, background film, which is fastened to the black mount. The blue film then slips through a slit in the white film and runs along a track, driven or retracted by the stepper motor.
Electronics
Qi Wireless Charging - wirelessly charges phone as well as detects when phone is present in the device
USB Rechargeable Battery - Micro USB compatible battery management + charging IC for Li-Ion battery
Boost Converter - 3.7V battery is boosted to 5V for MCU/sensors and 12V for stepper motors
Motor Drivers - three drivers to control 4-wire stepper motors
Button - soft, tactile pause button paired with plastic button cover for a smooth and silent press
Design for Manufacturability/Assembly
The alpha prototype for Count was fabricated out of sanded SLA prints, finished with soft touch paint though an overseas contract manufacturer.
Although the parts are 3D printed, they were designed with injection molding in mind, taking into account mold orientation and additional side-actions as well as utilizing features such as ribs and gussets.
There are also many design considerations to aid with the assembly process such as alignment chamfers, uniform fastener types, and wiring service loops.
Process
© Julian Mickelson 2021