Symhpony

Mobile computing is a generic term describing one's ability to use technology 'untethered', facilitated by devices which provide mobile computer functionality.

Many types of mobile computers have been introduced since the 1990s, including the:

• Personal digital assistant
• Enterprise digital assistant
• Smartphone
• UMPC

Technical and other limitations of mobile computing

• Insufficient bandwidth

Sufficient bandwidth is necessary for the widespread use and it must be inexpensive. It took years for technologies like 3G and Wifi to establish and still the coverage is very limited, inherently causing limited usability of mobile devices.

• Security standards

When working mobile one is dependent of third party networks, this makes one vulnerable to unwanted access.

• Power consumption

Batteries with long life are needed for mobile computing. One of the biggest technological challenges is to constantly improve the durability of mobile power supply in order to cope with the demand of improvement. ₂

• Transmission interferences

Weather and terrain problems as well as distance-limited connection exist with some technologies. Reception in tunnels and some buildings is poor.

• Potential health hazards

Potential health damage from cellular radio frequency emission is not known yet. However, more car accidents are related to drivers who were talking through a mobile device. Also, cell phones may interfere with sensitive medical devices.

• Human interface with device

Screens and keyboards are too small, uncomfortable and tedious for many people to use.

1. GH Forman, J Zahorjan - Computer, 1994 - doi.ieeecomputersociety.org
2. David P. Helmbold, "A dynamic disk spin-down technique for mobile computing", citeseer.ist.psu.edu, 1996
3. MH Repacholi, "health risks from the use of mobile phones", Toxicology Letters, 2001 - Elsevier
4. Landay, J.A. Kaufmann, T.R., "user interface issues in mobile computing", Workstation Operating Systems, 1993.
5. T Imielinski, BR Badrinath "mobile wireless computing, challenges in data management- Communications of the ACM, 1994 - portal.acm.org

Mobile computing: in-vehicle computing and fleet computing

Many commercial field forces deploy a ruggedized portable computer such as the Panasonic Toughbook 29 (Toughbook is the trademarked brand name owned by Matsushita Electric Industrial and marketed by their international brand name Panasonic. Toughbook refers to its line of semi-rugged and rugged laptop computers. In 2005, Panasonic added the Toughbook Arbitrator mobile digital camera and mobile digital video recorder (DVR) system to their line. Toughbooks are commonly used by public safety (police, fire and emergency medical services), utilities, field service, construction, and military personnel.) with their fleet of vehicles. This requires the units to be anchored to the vehicle for driver safety, device security, and user ergonomics(Ergonomics is commonly thought of as how companies design tasks and work areas to maximize the efficiency and quality of their employees’ work.). The rugged laptops are rated for severe vibration associated with large service vehicles and off-road driving, and harsh environmental conditions of constant professional use such as in EMS, fire and public safety.

Other elements that enables the unit to function in vehicle:

• Operating Temperature: A vehicle cabin can often experience temperature swings from -20F to +140F. Computers typically must be able to withstand these temperatures while operating. Typical fan based cooling has stated limits of 95F-100F of ambient temperature, and temperature below freezing require localized heaters to bring components up to operating temperature(based on independent studies by the SRI Group and by Panasonic Toughbook R&D).
• Vibration: Vehicles typically have considerable vibration that can decrease life expectancy of computer components, notably rotational hard drives.
• Daylight, or sunlight readability: Visibility of standard screen becomes an issue in bright sunlight.
• Touchscreens: These enable users to easily interact with the units in the field without removing gloves.
• High-Temperature Battery Settings:. Lithium Ion batteries are sensitive to high temperature conditions for charging. A computer designed for the mobile environment should be designed with a high-temperature charging function that limits the charge to 85% or less of capacity.
• External wireless Connections, and External GPS Antenna Connections: Necessary to contend with the typical metal cabins of vehicles and their impact on wireless reception.

Several specialized manufacturers such as Gamber Johnson and LedCo build mounts for vehicle mounting of computer equipment for specific vehicles. The mounts are built to withstand the harsh conditions and maintain ergonomics.

Specialized installation companies, such as TouchStar Pacific, specialize in designing the mount design, assembling the proper parts, and installing them in a safe and consistent manner away from airbags, vehicle HVAC controls, and driver controls. Frequently installations will include a WAN modem, power conditioning equipment, and a WAN, WLAN, and GPS antenna mounted external to the vehicle.