Modeling of ADLs in its Environment for Cognitive Assistance

Jérémy Bauchet and André Mayers

Introduction

Cognitive assistance, in smart homes, aims at supporting occupants for the completion of their activities of daily living (ADLs)

Introduction (2)

Implies for the system a prior knowledge about the occupant its activities its environment

This knowledge is necessary for :activity recognition, as a prior step of cognitive

assistance in smart homes finally, for cognitive assistance

Plan

Introduction A model for the description of ADLs

a hierarchical approach the environment of completion

Taking into account the specific behavior of the occupant Implementation of the models Results and perspectives concerning activity recognition

and cognitive assistance Conclusion

A hierarchical model for ADLs description Two type of nodes : tasks and methods

a task : a goala method : a way to realize the task

→ a set of subtasks

→ and rules of integration of subtasks : partial or total sequence repetition or necessity constraint

A hierarchical model for ADLs description (2) Roots are abstract tasks (ADLs, IADLs) Leaves are methods of terminal tasks = an

atomic way to realise a concrete goal

Tasks can be common to several methods→ if common nodes are duplicate, this

model is a tree

Model of activity

A model of ADLsin its environment Environment of activity completion Includes all actors of activity completion

daily living objects furniture the occupant, as the actor of his own task

completion

→ e.g. : her/his current position

Description of the environmentof completion Static description :

Actors : fridge Events concerning actors

fridge : door opened, door closed

Dynamic description : Assertions, giving current value of several pieces of information concerning actors

<fridge, door, opened> <occupant, position, kitchen>

Links between activities andthe environment Events concerning actors in the environment

are associated with terminal methods events are a consequence of the concrete actions

of the occupant events can be observed via distributed sensors occurrence of events are used for activity

recognition

Links between activities andthe environment (2) Tasks and method are considered as

operators of a planning domain they have preconditions and effectsboth concern the environment

Taking into account the specific behavior of the occupant The activity model is a support for the

generic description of ADLs and IADLs

→ We need an occupant model to describe his/her specific comportment

An episodic memory for the occupant model Allows to precise how one occupant

usually completes an activity the method used for a given task the time slot of completion the location the sequence of subtasks

Implementation

XML library of tasks and methods (activity model) description of the environment episodic memory persistence

SVG graphical representation of the environment

Java XML parsing internal representation of the models and treatments SVG management

Results and perspectives : Concerning activity recognition Goal : to compute the probability of

completion of (I)ADLs given inputs Inputs are :

description of ADLseventscurrent timeknowledge about the occupant habits of life,

given by the episodic memory

Activity recognition

Description of activities, for step by step or global assistance

Preconditions → what has to be done before, where the activity can take place

Rules of integration for subtasks → how to complete correctly the activity

Episodic memory → anticipation process

Results and perspectives (3) :Concerning cognitive assistance

Conclusion