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What makes this system unique?

What makes this system unique?

What are the features one would want for school-aged children, grades
K–12? A large fraction of such children are in parts of the developing
world where electricity is not available at home, or often even at
school, so for many children, a low power consumption, potentially a
human-powered computer is a necessity, not a convenience. Teaching may
not even be inside, and certainly when children are at home, they
often will not be inside where conventional LCD screens are usable.
Children usually walk to and from school every day; weather is
unpredictable, rain, dirt and dust are commonplace. And cost is a
major consideration, if we are to bring computers and their great
power to help children learn to children everywhere.

The OLPC design reflects these realities, thanks to the work of our
design team, which includes OLPC staff, Quanta Computer, the Fuse
Project, Design Continuum, members of the MIT Media Lab and other
colleagues and friends. It also reflects a great focus on what can and
should be done to help bring the children the best possible learning
tool, and reflects decades of field experience of children using
computers in the developing world. Our thanks to them all.

   * It is sized for a child, who, due to their size, will be closer
to the screen than an adult with a conventional laptop. The system is
much lighter than a conventional machine, (somewhere less than 1.5KG),
and its industrial design is quite different than a commercial
"black/grey/white" laptop.
   * Friendly, colorful design; Visually distinctive: it's for kids!
Immediately recognizable as a "kid's machine".
   * Safety First: Soft, rounded edges.
   * It has a rugged handle for carrying easily, sized for chidren.
This reflects the needs of children walking to and from school or
other activities.
   * "Transformer" screen hinge: E-Book Mode for convenient reading
and a conventional laptop mode. It folds over into a "ebook", about
the size of a conventional book, with buttons exposed for controlling
viewer applications (or for use with games).
   * The screen can be "on" while the CPU and most of the motherboard
is suspended and powered down, while the screen is read or the machine
otherwise idle, allowing for major power savings in most common usage
modes, such as reading a book.
   * The screen refresh rate can be varied. When applications are not
changing the screen, we can reduce the refresh rate of the LCD to
conserve power.
   * Wireless mesh: Child-child sharing! OLPC Laptops are full-time
wireless routers. Mesh networking reduces the need for dedicated
infrastructure (e.g. access points and/or cabling), and extends
greatly the areas in which machines may be connected to each other
and/or to the internet.
   * The wireless antennae are diversity antennae, and rotate upward
using a rugged dual moulded nylon plastic design. When used rotated
above the LCD, the antennae work significantly better than
conventional built in antennae in existing systems or in Cardbus
cards. This significantly increases the area each machine can cover in
the mesh, and generally increases network performance. When closed,
the antennae cover the audio and USB connectors to help keep dirt out
of the connectors (as mentioned above, the case carefully moulds
around the connectors, both to increase ruggedness and to help keep
dirt and water out). Great care has been taken in the RF design, and
early measurements show a lower noise level than seen by Marvell on
any other design of theirs. We expect that the 802.11 networking in
this system will be substantially better than a conventional system.
   * The Marvell wireless chip can forward packets in the mesh
network, with the CPU suspended, and the CPU may resume if explicitly
addressed. Since the mesh network is so important, we want laptops to
be able to participate in the mesh to keep forwarding packets when
need be as efficiently as possible, and by suspending the processor we
can increase the running time of the wireless a factor of 3-4. If this
were not possible, children might need to disable wireless to preserve
battery charge; by doing so, the mesh would be much less effective.
   * The machine is rugged. The most common failures of laptops are
disk drives, fans, florescent back lights, power connectors, other
connectors, and contamination of keyboards. Our machine uses flash,
eliminating a disk, has no need for a fan, uses a rugged LED backlight
rather than a florescent light, and uses a sealed rubber keyboard. It
uses 2mm thick plastic, where a typical system might use 1.3mm.
External connectors are carefully molded into the plastic for greater
strength. The power connector is carefully chosen to be much more
durable than usual, and again, the case is moulded carefully around it
for greater strength. There are extremely few connectors in the
machine, primarily just connecting the keyboard assembly to the
motherboard (which is behind the LCD display). This eliminates most of
the cables and connectors you will find in most laptops. We will be
testing 500 systems to destruction this fall to identify anything we
can do to increase further its ruggedness. There are internal bumpers
to protect the display, and we are investigating external bumpers on
the outside of the case for additional shock protection.
   * Additionally, the design allows us to directly connect the video
output of the DCON chip to the LCD, enabling lower power drive of the
   * With these special power savings features, average power
consumption, is expected to be low enough (in the neighborhood of
1-1.5 watts in many usage scenarios) that if a child needs to generate
power for their laptop, they will get a good ratio of "work" to
"learn". A small child can generate at best 5-10 watts; a larger child
somewhat more. In contrast, conventional laptops often consume 20
watts or more, even when idle.
   * The industrial design includes a small lip to help seal the edge
of the machine when closed. While not water-proof, we expect a machine
in a child's backpack or hands in a rainstorm should not have problems
with water.
   * The keyboard is a rubber membrane keyboard, with quite nice feel
(and we continue to work on further improvements on it). This makes
the keyboard much more resiliant against both water and dirt, and
allows us to seal the keyboard in the base of the machine. The
keyboard is connected via a PS/2 interface to save power. Smaller key
pitch for smaller hands. A lighter 40 gram touch than normal
   * Novel dual-mode extra-wide touchpad, with dual sensor
technology. Supports pointing… plus drawing and writing. Supports
fingers, or a pen, pencil, or stylus...
   * Dual cursor control pads (w/Enter keys)
   * Internal microphone, plus a mic-in jack. Unique "sensor input"
mode. The audio codec can be used in a mode where direct voltage
measurements can be taken, enabling children to learn about
temperature, voltage, and many other physical phenomena with cheap
sensors without requiring any external adaptors. The educational
possibilities are limited only by your imagination.
   * Stereo audio with internal stereo speakers; Stereo Line-out jack
   * There are three USB2 connectors, allowing for many expansion
   * The power supply is tolerant of almost any voltage you might
have at hand for charging, either from a human powered generator or a
car or truck battery; accidental reversal of polarity will not damage
the machine.
   * NiMH batteries are chosen to enable high charging efficiency
from a generator (LiION batteries require very close control of
charging voltages, so any higher voltage would have to be clamped and
power wasted). Additionally, NiMH batteries have no safety problems
(LiION batteries, when they fail, can fail by burning at extremely
high temperature). And LiION batteries should be recycled carefully.
NiMH batteries pose no environmental concerns.
   * Power-efficient processor & electronics. Consumes 1/10th the
power of "normal" notebooks
   * Long battery life == more useful. Under typical use, the
computer should last the entire school day without requiring charging.
Avoiding disruption in class rooms, and/or the need for wiring (or use
of generators) in the class room for power is very important.
   * Removable battery packs, that are much lower cost than
conventional LiION battery packs. This enables easy swapping of
batteries so that one set might charge while another are in use.
   * Careful attention to environmental issues, no hazardous
materials, fully ROHS (Reduction of Hazardous Substances) compliant.

From the above, you can see that this is a novel system carefully
designed to solve the challenges outlined above, and not a typical
"laptop" in almost any dimension you care to name.

Where's the Crank? (you are asking...) Human power is still a major
program priority! Inside the laptop isn't always optimal as human
power is not always required. Human power stresses components. The
crank is great symbol, but not the most efficient for actual
generation. We are performing human motion studies: legs are stronger
than arms, but arms may be free while walking to school. AC Adapters
are already located on the ground/ and floor. Several types of
generators are under development, including one integrated with AC
Adapter. More freedom of motion will allow for optimum power

http://users.ntua.gr/karounos/ - skype: karounos

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