A smart device is an electronic device, generally connected to other devices or networks via different wireless protocols such as Bluetooth, NFC, WiFi, 3G, etc., that can operate to some extent interactively and autonomously. Several notable types of smart devices are smartphones, phablets and tablets, smartwatches, smart bands and smart key chains. The term can also refer to a ubiquitous computing device: a device that exhibits some properties of ubiquitous computing including–although not necessarily–artificial intelligence.
Smart devices can be designed to support a variety of form factors, a range of properties pertaining to ubiquitous computing and to be used in three main system environments: physical world, human-centered environments and distributed computing environments.
In 1991 Mark Weiser proposed three basic forms for ubiquitous system devices: tabs, pads and boards.
- Tabs: accompanied or wearable centimetre sized devices, e.g., smartphones, smart cards
- Pads: hand-held decimetre-sized devices, e.g., laptops
- Boards: meter sized interactive display devices, e.g., horizontal surface computers and vertical smart boards.
These three forms proposed by Weiser are characterised by being macro-sized, having a planar form and by incorporating visual output displays. These were also envisioned more as information appliances. If we relax each of these three characteristics we can expand this range into a much more diverse and potentially more useful range of Ubiquitous Computing devices. Hence, three additional forms for ubiquitous systems have been proposed:.
- Dust: miniaturised devices without direct HCI interfaces, e.g., Micro Electro-Mechanical Systems (MEMS), ranging from nanometres through micrometers to millimetres. See also: Smart dust.
- Skin: fabrics based upon light emitting and conductive polymers and organic computer devices. These can be formed into more flexible non-planar display surfaces and products such as clothes and curtains, see OLED display. MEMS devices can also be painted onto various surfaces so that a variety of physical world structures can act as networked surfaces of MEMS.
- Clay: ensembles of MEMS can be formed into arbitrary three-dimensional shapes, as artefacts resembling different kinds of physical object. See also: Tangible interface.
Smart Devices can be characterised as follows:
- A set of system hardware & software ICT resources. This set is usually static fixed at design time
- Dynamic component-oriented resource extensions & plug-ins (Plug and play) of some hardware resources
- Remote external service access and execution
- Local, internal autonomous service execution
- Access to specific external environments: human interaction, physical world interaction and distributed ICT / virtual computing interaction.
- Ubiquitous computing properties.
Common types of smart devices include:
- Tab and pad type smart devices that often act as personalised smart mobile devices
- Smart environment devices.
Smart Mobile Devices can be characterised as follows:
- Multi-purpose ICT devices e.g., personal office, mobile phone, camera, games console, etc.
- Multi-functional support eases access & interoperability of multi-functions at run-time but this can lead to a decreased openness of the system to maintain (upgrade) hardware components and to support more dynamic flexible run-time interoperability.
- Mobility: devices are either often loosely bound to users, i.e., accompanied or carried, or can be more tightly bound to users, i.e., wearable computing
- Personalised, configured to a specified owner. Device access can be secured only for the owner.
- Operates as a single portal, e.g., a Web portal.
- This can combine internal (to the device) application services and multiple external services
- External services are typically accessed via a remote-area or local area wireless network
- Smart mobile device service access is characterised by:
- Open service discovery
- Intermittent resource access.
- A locus of control that resides in the smart device.
Ubiquitous Computing Properties
Weiser’s vision for ubiquitous computing can be summarized in terms of three core properties:
- Devices need to be networked, distributed and transparently accessible.
- Human Computer Interaction with devices is hidden to a degree from its users.
- Devices exhibit Context awareness of an environment in order to optimise their operation in that environment.
It is proposed that there are two additional core types of properties for UbiCom systems:
- Devices can operate to some extent autonomously, i.e., without human intervention, be self-governed.
- Devices can handle a multiplicity of dynamic actions and interactions, governed by intelligent decision-making and organisational interaction. This may entail some form of artificial intelligence in order to:
- handle incomplete and non-deterministic interactions
- cooperation and competition between members of organisations
- richer interaction through sharing of context, semantics and goals etc.
However, It is hard to fix a closed set of properties that define all ubiquitous computing devices because of the sheer range and variety of ubiquitous computing research and applications. Rather than to propose a single definition for ubiquitous computing, a taxonomy of properties for ubiquitous computing has been proposed, from which different kinds or flavours of ubiquitous systems and applications can be composed and described.
The term Smart Device Environments has two meanings. First, it can refer to a greater variety of device environments. Three different kinds of environments for devices can be differentiated:
- Virtual computing environments that enable smart devices to access pertinent services anywhere and anytime.
- Physical environments that may be embedded with a variety of smart devices of different types including tags, sensors and controllers. These can have different form factors ranging from nano to micro to macro sized.
- Humans environments: humans, either individually or collectively, inherently form a smart environment for devices. However, humans may themselves be accompanied by smart devices such as mobile phones, use surface-mounted devices (wearable computing) and contain embedded devices (e.g., pacemakers to maintain a healthy heart operation).
Second, the term Smart Device Environments can also refer to the concept of a smart environment which focuses more specifically on the physical environment of the device. The physical environment is smart because it is embedded or scattered with smart devices that can sense and control part of it.
Information Appliances versus Smart Devices
Although smart devices partially overlap in definition with specific types of appliance such as Information appliances, Smart Devices are characterised and differ in several key ways. First, Smart Devices in general can take a much wider range of form-factors than appliances. Second, Smart Devices support the ubiquitous computing properties. Third information appliances focus on remote interaction with computing environments that tend to be personalised whereas Smart Devices can also focus heavily on impersonal physical world interaction. Four, the term appliance generally implies that devices are task specific and under the control of some embedded system or application specific operating system, whereas Smart Devices may support multiple tasks, e.g., a mobile phone can act as a phone but also as a games console, music player, camera, etc.