When I started in the Hapkit project, Hapkit 1.0 had been designed by Allison Okamura and Tania Morimoto in 2013 as a low-cost version of the Haptic Paddle to be used in a Massive Open Online Course (MOOC) on the topic of haptics. Hapkit 1.0 uses laser-cut structural components, a Maxon motor obtained as a surplus item and an integrated Arduino board that contains a motor driver and a magnetoresistive sensor that is used to measure the angular position of the motor shaft. In order to make Hapkit more accessible to students and educators, we evolved the design in terms of its structural materials, drive mechanism, and mechatronic components through lessons learned at Stanford, online courses, and perceptual and educational studies performed in collaboration with the Stanford School of Education and the University of British Columbia.

The final design (to date) of Hapkit, Hapkit 3.0, is made out of 3D printed structural components and is designed in two parts in order to enable students to customize their device and create their own handle designs. It also contains other features that make it more robust for classroom use such as suction cups at the base as well as snapping mechanisms for ease of assembly. Hapkit 3.0 features an easy-to-assemble capstan drive transmission and uses an inexpensive Mabuchi motor that can be purchased from Jameco for $3.49.