Hardware Specification - Alex

The proposed human-computer interface (HCI) hardware for the e-trolley consists of:

• An embedded computer with low voltage embedded CPUs which will be responsible to: 1) run the software which controls the motion of the e-trolley 2) temporarily save the current user's configuration 3) handle the wireless network connectivity which will transfer and save each user's configurations (favorite products, checkout etc.) to the supermarket's central database server. For the network's security, SSL and IPSec are proposed to be used.
  

• A 10.1" LCD Touch Screen Monitor with embedded speakers. Elderly people who have sight problems can use the screen reader functionality.
  

• An Absorbed Glass Mat (AGM) Battery to supply power to the wheel propultion mechanism. An AGM battery does not leak, freeze and does not require any maintenance. Thus, the battery will not contaminate the food products within the supermarket if the battery is damaged and can enable the e-trolley to be stored for a long period of time without charging.
  

• A force-sensing joystick, similar to the one electric powered wheelchairs use, to control the position of the e-trolley. It is intended to be used as a human-friendly and ergonomic interface for elderly people to operate our e-trolley with a limited wristle motion required. The speed of the trolley should be between 2 and 4 miles per hour but further research is needed to establish the optimal speed.
  

• Elderly people have a slow reaction time therefore Proximity Sensors are suggested to be used in order to identify obstacles and avoid collisions.