Michael Philetus Weller

Posey: instrumenting a poseable hub and strut construction toy

We describe Posey, a computationally-enhanced hub-and-strut construction kit for learning and play. Posey employs a ball and socket connection that allows users to move the parts of an assembled model. Hubs and struts are optocoupled through the ball and socket joints using infrared LEDs and photosensors. Wireless transmitters in the hubs send connection and geometry information to a host computer. The host computer assembles a representation of the physical model as the user creates and configures it. Application programs can then use this representation to control computational models in particular domains.

Electrostatic latching for inter-module adhesion, power transfer, and communication in modular robots

A simple and robust inter-module latch is possibly the most important component of a modular robotic system. This paper describes a latch based on electric fields and capacitive coupling. Our design provides not only significant adhesion forces, but can also be used for inter-module power transmission and communication. The key insight presented in this paper, and the factor that enables electrostatic adhesion to be effective at the macroscale, is the use of electric field attraction to generate frictional shear forces rather than electric field attraction alone. A second important insight is that a specific degree of flexibility in the electrodes is essential to maximize their mutual coupling and the resulting forces - electrodes which are too flexible or too rigid will perform less well. To evaluate the effectiveness of our latch we incorporate it into a cubic module 28 cm on a side. The result is a latch which requires almost zero static power and yet can hold 0.6 N/cm2 of latch area.

Escape machine: teaching computational thinking with a tangible state machine game

We present a methodology for building objects-to-think-computationally-with and illustrate its application in developing our Escape Machine game. The input mechanism for this game is a tangible state machine built with Posey, our computationally enhanced construction kit. Through manipulating this state machine children create an algorithmic specification for the behavior of both the avatar and its enemies in an attempt to navigate a maze without being eaten. We outline several strategies for success at Escape Machine and discuss how it embeds an important computational thinking concept in interaction with a tangible device.

Design of prismatic cube modules for convex corner traversal in 3D

The prismatic cube style of modular robot is a promising design for realizing self-reconfigurable 3D lattices. Cubic lattices with prismatic transitions simplify many aspects of the hardware and planning control needed for reconfiguration. Despite much research on how cubic modules can coordinate to reconfigure, until now these transitions have not been fully demonstrated in hardware.We describe our movement primitives for both orthogonal and convex corner transitions with prismatic cube modules. We discuss the design of a hardware module capable of performing these transitions, as well as assess the performance of this hardware in an initial demonstration of these transitions.

Tangible sketching in 3D with posey

Posey is a physical construction kit that is instrumented to capture assembly and configuration information and convey it to a host computer. We have used Posey to build applications that deploy a reconfigurable physical model as a tangible interface for various domains. We demonstrate these applications to support a case for computationally enhanced construction kits as a semi-general interaction modality.

State machines are child's play: observing children ages 9 to 11 playing Escape Machine

We developed Escape Machine, a puzzle game in which children control the behavior of characters in a maze by manipulating a tangible state machine built with Posey, our computationally-enhanced hub-and-strut construction kit. We observed children ages nine to eleven playing the game in several sessions. The qualitative results of this observation validate the promise of Posey and Escape Machine to engage children in manipulating algorithmic specifications for behavior.

An optocoupled poseable ball and socket joint for computationally enhanced construction kits

We present a novel design for connecting pieces of a computationally enhanced construction kit, an optocoupled ball and socket joint. Unlike other existing connectors, our joint is poseable and allows both the topology and dynamic configuration of a kit assembly to be sensed. We provide a survey of existing computationally enhanced construction kit connectors and describe the technical details of our design.

Exploring architectural robotics with the human hive

We present an activity we developed to demonstrate bottom-up form construction, the human hive. Participants team up to construct a hive structure from large interlocking cardboard blocks. Each participant is given a visual rule that describes where new cells should be added to the hive. The design of these rules guides the form of the structure that emerges from this uncoordinated activity. Bottom-up, distributed methods for specifying physical forms and behaviors are central to the emerging field of architectural robotics that deals with designing objects composed of self-reconfiguring materials.