Checklist imageHere is a great checklist for wearable devices. When we do a design we check all of these things and more. Often we need to use our engineering judgment on the tradeoff between size, cost, testability, and manufacturability of the board.

Power

  • What size battery?
  • What is the appropriate battery lifetime?
  • How often do various parts of it need to be on?
  • What is the maximum current draw (also determines battery size)?
  • How will the battery be charged: wirelessly, plugged in, or replaceable batteries?

Wireless

  • What is the appropriate type of wireless transmission?
  • Is a gateway needed or will it connect directly to the Internet?
  • What is the impact on the battery, size and lifetime?
  • What type and size of antenna is needed?
  • How often does it need to be on?

Sensors

  • What is the appropriate tradeoff between cost and accuracy?
  • What accuracy and sensitivity is needed? Is calibration needed?
  • How will the sensors be tested and calibrated?
  • If there are biological sensors, how will the signals be picked up from the body, contact or non-contact, invasive or non-invasive?

Flex Circuits

  • What is the bend radius?

Software

  • Where does the data analysis take place, on the device or elsewhere?
  • How smart does the device have to be (smarter generally means more power and larger)?
  • What is the protocol for communication, standard or proprietary?
  • How will software updates be done, over the air, by plugging in, or not at all?
  • Will there be wired communication?  During charging?

Packaging

  • How small is the space for electronics?
  • How will everything fit?
  • Where will the antenna be located (away from metal and not too close to the body)?
  • Does it need to be sealed from dust and moisture?  To what water depth is it sealed?