Kinect

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In AIRLab we have currently two (first-generation) Microsoft Kinect sensors. The Kinect is defined as a "motion sensing input device": from the point of view of a robotics lab it is an interesting multisensor device which has a very low price in comparison to the hardware provided.

Connecting the Kinect

Contrary to what you may expect, the issue is not straightforward. One awkward feature of the Kinect is, in fact, its bizarre combined data+power connection system. The cable going out of the base of the device ends in a large, non-standard connector with an orange inner part. Such connector is intended for the strange combination USB data cable + 12V DC power adapter that Microsoft puts in the box along with the Kinect (and which, of course, sports a matching connector, also with orange interior).

When a Kinect is connected to its power supply/USB cable, from one side of the non-standard socket+plug goes out a cable going to the Kinect, while from the other side go out two cables: one that goes to the power adapter, and another terminating into a standard USB connector. To use the Kinect you have to connect the power adapter to a 230V AC power outlet, and the USB plug to a socket of your PC. Unfortunately, this setup is very inconvenient for robot-mounted Kinects. Robots don't have 230V AC power outlets, so you can't use the standard power supply. However, you must connect it to the Kinect if you want to connect the sensor to a PC, because the USB cable is physically linked to the useless power supply. So you have to leave the non-standard plug and socket connected, which provides you with the USB cable (which is good) and a useless, dangling power supply (which is not good). Moreover, the Kinect does not work... because it is not powered.

The solution to this problem is, of course, to hack the Kinect. Precisely, to cut the cable linking the 230V AC power supply to the non-standard connector and rejoin the two sides of the cable with a suitable two-pole connection. We used two common "Faston" blade connectors for this. So, when you want to use the Kinect on 230V AC power, you keep the Fastons connected. When, instead, you want to put the Kinect on board a robot, you disconnect the Fastons, put the Kinect power supply away. You still have the male and female non-standard connectors joined: so you still get the USB cable for PC connection and a couple of unconnected Fastons. The final thing to do is connect the Fastons to an onboard power supply capable of supplying 12V DC. For instance, a lead battery. Mind the polarity!