Know How... 158: Intel RealSense, Thermoelectric Cooling, and Win10 Gestures on a MacBook

Intel's take on Microsoft's "Kinect" is called RealSense, Thermoelectric Cooling Basics, DIY Active Cooler, and a way to use Windows 10 Gestures on your MacBook.

Let's talk about Intel RealSense!

• It's Intel's take on Microsoft's "Kinect"


• It was developed primarily as a hardware implementation of "gesture-based" IO


• They just released their newest version of RealSense, the R200 and gave away units at one of the IDF sessions. (I wasn't able to get in. :( )

The new version uses a variety of tech

• A 2d camera for conventional image capture // an IR camera for depth perception // an IR laser projector


• A special Intel chip in the unit captures the 2D image, then uses the IR image to create a 3D image.

This enables a few interesting applications:

1. It gives you 22 tracking points per hand.


2. It allows for interesting camera tricks... like green-screen-less chroma keying. (Since it can scan for depth, you simply tell it not to include anything past a certain distance.)

TEC (Thermoelectric Cooling Basics)

A TEC is a solid-state device that uses the "Peltier Effect" to create a "heat flux" between two different materials, acting as a "heat pump" that transfers heat from one side of the device to the other.

You make a TEC by placing two semiconductors, made of different materials, physically parallel to one another, but electrically wired in series. You then attach each semiconductor to a thermally conductive plate. (Ceramic)

• You need two different semiconductors because you want two different electron densities


• When you charge the device (one semiconductor is postive, the other side is negative) you will get a flow of DC current across the junction between the two semiconductors


• As the current jumps across the junction, one side of the device will get hot, and the other side will get cold.


• (The heat from the cold side is transferred to the hot side... PLUS the heat generated by the current flowing across the junction.)

Advantages vs. Closed Cycle Refrigeration

• Small and simple (no moving parts)


• Long-lived (100,000+ hours)


• Cooling effect is easily regulated (by adjusting voltage)


• More durable (in most cases) than a refrigeration unit

Disadvantages vs. Closed Cycle Refrigeration

• Maximum heat difference of 70 degrees C (The cold side can be no colder than 70 degrees cooler than the hot side.)


• Inefficient. (10-15% vs. 40-60% for Closed Cycle Refrigeration)


• Efficiency drops as more heat is pushed through the TEC


• You can stack TECs to increase cooling potential, but you create an increasingly inefficient devices as you add more TECs.

Let's Identify our TEC!

• All Peltier Elements will have an ID stamped (usually) on the Hot Side of the element.


• For example "TEC1-12706" (These are the ones we're using for our project)
  
  
  • "TE" stands for "ThermoElectric)
  
  
  • "C" means "standard size" vs. "S" for "small size"
  
  
  • "1" indicates how many stages are in the device
  
  
  • "127" indicates how many P-N couples are in the device
  
  
  • "06" indicates how many amps the device is rated for

So... our TEC is a Standard 1-stage element with 127 positive-negative couples that can handle 6amps at 12 volts, or 72 Watts. Since our device is 10-15% effective, that 72 watts will get us less than 11 watts of cooling power.

Windows 10 Gestures on a Mac

Trackpad++

• Who's this for? People running


• The


• Apple

These show notes have been truncated due to length. For the full show notes, visit https://twit.tv/shows/know-how/episodes/158

Hosts: Fr. Robert Ballecer, SJ and Bryan Burnett

Technical Director: Alex Gumpel

Sponsors:

• Ring.com/KNOWHOW


• ifixit.com/twit enter code KNOWHOW