Smart Table

Overview

Smart Table is a table that can track and identify multiple objects simultaneously when placed on top of its surface. The table has been designed to support a smart problem-solving environment for early childhood education in a project called Smart Kindergarten. The incorporation of location information and identification provided by Smart Table into context-aware computing applications is presented here.

The overall system architecture is described in detail unleashing the core of the hardware, namely the printed circuit boards. Utilization of Hall effect sensors mounted on these boards enable tracking of objects when they are tagged with magnetic labels. A distributed sensor scanning technique is implemented on the sensor boards. The sensor status information of the sensor boards is sent to a host over an RS-485 communication bus for further processing.

The software architecture and the corresponding implementations involve three different computing platforms ranging from an 8-bit RISC microcontroller from Atmel through a StrongARM CPU from Intel and to a high-end Pentium-4 microprocessor. The proposed object localization and identification algorithm has been simulated in Matlab. The algorithm was successfully transferred to a fixed-point implementation which runs on embedded hardware and satisfies real-time requirements.

The system performance of the final implementation of Smart Table is presented here. Videos of Smart Table demonstrate that the system is ready for deployment outside the laboratory environment.

System Specifications

• Surface size: 1.2 x 0.8m
• Object position accuracy: <= 10mm
• Object orientation accuracy: 22.5grad
• Maximum number of objects: 32
• Support for passive objects
  (no electronic circuits required on object)

This material is based upon work supported by the National Science Foundation under Grant No. ANI-0085773. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF).