Trackball Mouse

A couple years ago I bought this neat mouse on Amazon. It is surprisingly useful. I can use it to remote control my computer from my bed. It is also useful for controlling my Avegant Glyph when not sitting at a desk.

Avegant Glyph Review

Two years ago I made a post about a device called Avegant Glyph. I ended up investing in the Kickstarter. The estimated delivery during the Kickstarter campaign was December 2014. I finally got the Glyph two days ago.

It is a very cool device, but fell short of my expectations. Initially I spent a lot of time trying to get the position of the display calibrated for my eyes. It was very difficult to calibrate - I couldn't get a clear view of the entire rectangular display. The nose pieces that came with the device keep the display too far from my eyes. I found that removing the nose piece helps me get closer to the display, getting a clearer picture. However, I still can't get a completely clear view of the corners of the display even with my eyelashes touching the lens. The device is also a bit uncomfortable without a nose piece.

Ignoring the calibration issues, the quality of the display is amazing. Colors are very pure and reading text is easy. The display quality looks much better than the Oculus Rift developer versions. However, the resolution of the display is not very high.

Originally I was hoping this could be used as a complete replacement for my desktop monitor. The calibration issues really prevent this from working well. It is annoying to not be able to see text in the corner of the display clearly with both eyes. I tried watching a movie with the device while lying down. This worked well. The weight of the device was supported by the bed, so it was not uncomfortable. The corner calibration issues were hardly noticeable while watching the movie (probably because focusing on the edges wasn't necessary).

Raspberry Pi Thermostat Instructions

Here are some details on how I put together my Raspberry Pi thermostat.



My apartment's thermostat uses a very simple mechanism to control the heater:



Connecting the red wire to the white wire turns on the heater. Near the center of the thermostat is a glass vial containing some mercury. If the vial tilts to the right the mercury creates a connection between the wires. I attached the two black wires on the bottom and use the Raspberry Pi to control the connection between the wires. The original thermostat remains fully functional: the heater will turn on if either the Raspberry Pi or the original thermostat signal it to turn on.



Materials used:

• Raspberry Pi 2 Model B
• USB Wifi
• Pi Cobbler Plus
• Power supply
• SD card
• Songle SRD-05VDC-SL-C Relay
• Breadboard
• Wires

The relay module controls the connection between the two heater wires. GPIO output from the Raspberry Pi can turn the connection on/off. The connection is off by default - even when the Raspberry Pi is powered off. I SSH into the Raspberry Pi to control the GPIO pin over the Internet.

Raspberry Pi Thermostat

I connected a Raspberry Pi up to the heater in my apartment. Now I can control the heater over the Internet.

Update: more details posted here.

An Update on Baka

[previous post]

Although Baka Analytics has stopped updating, Baka is still alive. The occasional gaps in the data were due to Baka chewing through the wire which connects the magnetic sensor to the Raspberry Pi (which I had to fix several times). The outage since September 12 is a more serious issue: all of the USB ports on the Raspberry Pi stopped working. I think Baka caused this by urinating on the Raspberry Pi (which was stored next to his cage). I have ordered a replacement Raspberry Pi to use on another project, so it is unlikely I will restart Baka Analytics.

Baka's record was running 17.31 kilometers in a single night. In total Baka was recorded running 682.29 kilometers.

Metaball Go

Today I worked on a small HTML5 project: http://www.byronknoll.com/go.html

This is the board game Go rendered using metaballs.