Hardware Lifetime and Survival

From OLPC

Jump to: navigation, search

We can expect that demand for OLPC will always outstrip supply. Therefore, it is prudent to extend hardware lifetimes to the extreme, so to minimize the pressure to replace units that have failed. A design goal of 10 years for OLPC hardware is a reasonable target, as there should never be any 'built-in' obsolesence'. This is another aspect of the uniqueness of the hardware design.

The current OLPC implementation has a design lifetime of five years OLPC Bitfrost#Laptop disposal and transfer security. As successive generations of OLPC are born, ideally its creators work to improve its longevity. Three aspects are important in extending lifetime:

Amplifying Component Lifetimes

A partial list of components and their limiting design criterion includes

  1. keyboard - number of keypresses
  2. battery - number of charge/discharge cycles, currently 2000 charge/discharge cycles
  3. hinges, etc - number of movements
  4. NAND flash - number of writes
  5. DRAM memory - number of writes
  6. enclosure buttons - number of uses
  7. any IC fans - hours of operation
  8. speaker lifetime
  9. microphone lifetime
  10. any spring-loaded battery contacts
  11. connector lifetimes - couple/decouple cycles (for USB, power, mic, line-out, SD Card slot)
  12. power block - lifetime of braided wiring, and connectors

Later hardware versions hopefully can incorporate various extended life components, as tabulated above.

Field Replaceable Modules (FRU)

This permits the efficient replacement of shorter lifetime components. Modular design

Mitigating Events that Kill Machines

Laptop vendor warranty claims could identify the most frequent kinds of events that kill laptops. Without this data, one could still guess that the following are more frequent:

  1. dropping laptops
  2. crushing laptops (sitting on them, etc)
  3. water seepage
  4. water immersion
  5. baking in the sun for extended periods, either open or closed
  6. lost within water bodies

Makers of ruggedized laptops can suggest ways to make the OLPC more rugged. Failing these dialogs, the following hardware enhancements are prioritized by relative cost/benefit:

  1. all connectors should be upgraded to water-proofed varieties
  2. all enclosure seams should be sealed - this also permits the OLPC to be washed like an animal
  3. additional re-enforcements (skeleton, diagonal members) to strengthen against crushing the units
  4. increased survival to dropping
  5. OLPC should be proven to survive immersions upto 5 feet of water
  6. OLPC should be made to float on water (being sealed, the captured air should float the unit)
Personal tools
  • Log in
  • Login with OpenID
About OLPC
About the laptop
About the tablet
Projects
OLPC wiki
Toolbox