|dc.description.abstract||Social isolation for persons with cognitive impairments due to aging and/or disease is common and widespread. Those people who have diseases such as early Alzheimer’s and dementia tend to forget what they have to do to reach their destination and why they are going there when they go outside unaccompanied. The purpose of this research is to develop technical components of one device called Mobility Assistance (MA) for those persons with cognitive impairments. This MA device can store a pre-defined route and can also track the navigational route of a person. According to context (standing, running, walking, in vehicle) and position, the MA can detect likely deviations from the expected route. The MA device can give the lost user various cues to return to the route. If the user
fails to resume the correct route or the user encounters an emergency (for example: falling down), the MA device can alert a caregiver.
There are three modules in this system: sensor, mobile phone and PC. The sensor module is composed of an analog accelerometer which provides information such as steps, distance and movement information, an analog compass which provides direction information, and a Bluetooth transmitter. The main use of the sensor module is for dead-reckoning navigation when GPS is unavailable. It is also used to detect context such as sitting, running, or riding in a vehicle. The mobile phone module can determine any deviations from a programmed route by using GPS and dead-reckoning navigation. The mobile phone can also prompt/alert the mobile user and communicate with a remote caregiver. The PC module can be used for route entry and can download the routes to a Mobile phone.
In this research we have developed and implemented the following components of the MA device:
1. System software to receive and store transmitted data from the inertial sensor.
2. System software to receive data from a GPS module.
3. Algorithms for direction determination.
4. Algorithms to interpret the sensed data to compute steps and distance of wearer traveled.
5. Interaction software, running on a PC, to present the data from PDA-phone appropriately.
6. Interaction software, running on a PDA-phone, that allows the user to setup conection between phone and PC.
So far, the communication between sensor and mobile phone and between mobile phone and PC work well. Furthermore, the analog compass can provide accurate direction information within a ±2? margin. However, the analog accelerometer still can not provide accurate step detection and stride length information. Future work will be needed to address these issues.||en_US