Smartphone guides blind people without GPS
Fujitsu has worked with Japan’s National Institute of Information and Communications Technology (NICT) to develop an indoor support system for the blind that uses ultra wide band (UWB) technology on a smartphone.
The system provides real-time positioning data, even indoors where GPS cannot be used. It then provides audio instructions on the distance and direction to a destination to help guide the blind.
According to NICT and Fujitsu, the positioning system based on UWB wireless technology can provide positioning indoors to an accuracy of less than several tens of centimetres. This is far better in-building accuracy than GPS, which relies on signals from satellites.
The systems uses impulse radio UWB (IR-UWB) technology to measure distances. It is configured with several base stations positioned in an indoor area as part of the infrastructure, several mobile stations?one for the user and others for destinations?and a PC that controls the entire system.
“The basestations first measure the distance between each of the mobile stations (for the user and the destinations) and the basestations with a margin of ranging error of less than 30 centimetres, and the control PC calculates and gives the positioning data based on the ranging results in real time,” said the firms.
The obtained position data is then sent to the user’s mobile station and then via Bluetooth to a smartphone, where the user’s location and the location of the destination are simultaneously displayed using a special mapping application.
The smartphone used is a Fujitsu-manufactured docomo NEXT series ARROWS X LTE F-05D released from NTT DoCoMo, and the mapping application was developed for Android 2.3.
UWB is notable because it transmits over a range of radio frequencies using low power and overlapped frequencies. A feature of the technology is that it can coexist with other wireless systems. UWB is generally divided into two frequency bands: UWB lower band (3.1-4.8 GHz, except in Japan, where it is 3.4-4.8 GHz) and UWB upper band (6.0-10.6 GHz, except in Japan, where it is 7.25-10.25 GHz).
Within UWB, IR-UWB uses extremely short pulses on the order of nanoseconds. Because a nanosecond pulse provides very precise time resolution, ranging with an error of less than 30 centimetres is available by measuring the pulses.
NICT and Fujitsu plan to make further advancements to push forward the technology for assisting the blind by building a system with additional sensors that can detect obstacles on the road.
The system will be demonstrated at Wireless Technology Park 2012, held July 5-6 at Pacifico Yokohama.