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Lucas Walter
Attended University of Washington
Lives in Seattle
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Lucas Walter

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Positioning system with an area illumination sync signal plus two x and y scanning IR line lasers.

IR LEDs provide the start of a timing sequence.  A microcontroller (attached to the photodiode) starts a counter (with fine-grained time resolution) when it receives that initial sync signal, and then waits for the X and Y line lasers to illuminate the diode.  Depending on the time elapsed, the microcontroller can directly map the time delay to X and Y angular measurements. Using multiple photodiodes and knowing the rigid body relationship between them, the microcontroller can calculate the entire 6-DoF pose of the receiver.
While walking around the Bay Area Maker Faire this weekend, I stumbled across an amazing piece of technology: Valve's "Lighthouse" tracking system. Valve's demos were (supposedly) a major contributor to Oculus' fundraising efforts and ultimate sale to Facebook, and this device may have been a ...
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Only halfway through so far but some of the risk assessment is sloppy: we have good data on distribution of impactor sizes (e.g. 1 multi-megaton event per century), but don't apply data on the distribution of human population (which is trivial to get and analyze), the speaker here just speaks of 'luck' in whether a dense urban area vs. Tunguska forest or ocean or whatever is hit.

The nice thing about asteroids/comets as existential risks is that we should get a lot of well documented near misses and possibly severe but local damage before encountering a Chicxulub- so the political motivation to detect threats and alter trajectories can grow steadily. Of course we should be doing more than we are now to detect in advance. 
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The base platform is a Traxxas 1:10-scale radio-controlled (RC) brushless motor rally car that is capable of reaching 40+ mph speeds. The sensor suite consists of a Hokuyo 10m scanning lidar, Pixhawk's PX4Flow optical flow camera, a Point Grey imaging camera, and SparkFun's Razor inertial measurement unit. Control and autonomy algorithms are processed on-board with an embedded NVIDA Jetson TK1 development kit running the Ubuntu Linux operating system with "The Grinch" custom kernel. The TK1's pulse width modulation (PWM) output signals drive the motor electronic speed controller and steering servomotor, bypassing the RC receiver.

Someone ought to take all those components, shrink them down, integrate them with each other, make them inexpensive through economies of scale, and make a low-ish cost off the shelf ROS vehicle.
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I just started using Viz3d in +OpenCV  3.0.0-rc1, it works okay but the inability to set lights in the scene means objects viewed edge on are going to be black (see 0:46), which is a dealbreaker for me currently.  Also it would be great to have a method to save the current displayed window to a cv::Mat.

With some more features is could be a great way to visualize things very quickly in 3D.  For 2D highgui and imshow is the best way to start manipulating pixels out of any graphics library- it's fewer lines of code than anything else I've ever seen, no initialization or pages of boilerplate code that every project has to duplicate.  Having a 3D equivalent would be fantastic.

I'd take my problems to answers.opencv.org but I get a 'OpenID 2.0 for Google Accounts has gone away' when trying to login with google, and when I enter my email address for password recovery it claims to have sent a recovery email but I'm yet to receive it.

That answers site has always been in the shadow of stackoverflow, there are a lot of unanswered questions, and not many reputation points to be gained for going to the effort of answering.  Not every library needs a dedicated stack-alike site.
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I didn't get timestamps but at one point Ng says intelligent computers are a long way off, but then in another expresses surprise at the last five years of progress.

Is this on youtube?  I found some videos from +NVIDIA here: https://www.youtube.com/playlist?list=PLZHnYvH1qtOaW8_l6XgrFqqp2V2Q3hMly but not this one.
 
My GPU Technology Conference talk has been posted online.  The talk includes several new ideas/results that I haven't talked about before, including a new demo of Deep Speech, new face recognition results (far better than human-level), and a simple slide showing how I think about developing ML systems. Even though it's a long, full-length talk, and even if you have heard me speak elsewhere on Deep Learning, I hope many of you will find this worth watching!  Go to: http://www.ustream.tv/recorded/60113824
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Projector mapping pixelated textures onto real world objects to make them look like they are somewhat primitively 3d rendered is a really cool idea.
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http://sentinelmission.org/sentinel-mission/ Sentinel is a space-based infrared (IR) survey mission to discover and catalog 90 percent of the asteroids larger than 140 meters in Earth’s region of the solar system. The mission should also discover a significant number of smaller asteroids down to a diameter of 30 meters. Sentinel will be launched into a Venus-like orbit around the sun, which significantly improves the efficiency of asteroid discovery during its 6.5 year mission. 

Late in the talk it is mentioned that we have the ability to predict trajectories for about a 100 years, then we would need to launch another mission like this.  But wouldn't having a more detailed map of every moderate sized object in the nearby solar system (combined with more computational power) increase the quality of our trajectories greatly?  Or does the influence of non-inert actors (solar wind?) build up too much error regardless?

Can they sell the data to +Planetary Resources?

It looks like +Sentinel Mission is a rebranded B612 Foundation.
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I really like these live recordings over the official studio versions on +East India Youth channel- the distortion, echoes, feedback, and performance variations- it all makes the sound bigger and more powerful and real.  If I were to do music I'd want to incorporate all that, have a finite element acoustical simulations of complex rooms with moving objects in them (probably would need a big GPU to run it on) and speaker models that capture all their imperfections.  Maybe instead of releasing the music as a set recording it would instead be an executable that resimulates the performance on every play.

Heaven, How Long is around 11:30
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No tethers or gantry in the real competition as they are using here to practice: http://www.youtube.com/watch?v=6guQ2SlSL3k&t=1m14s "if it does fall it could break an arm, it could break a hydraulic line"

Are they or other teams working on fall mitigation- holding out arms but flexing on impact to absorb energy or other strategies (can the robots even move that fast?).


http://www.youtube.com/watch?v=6guQ2SlSL3k&t=1m50s "A team of 25 working 12 hour days 7 days a week" in the remaining few weeks before the competition.
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To view a full screen youtube video (or whatever) and lock the computer: install xtrlock, then press alt-f2 and enter xtrlock and the pointer will turn into a lock (it would be nice to even get rid of that), and the playing video will return to fullscreen.

http://superuser.com/questions/188836/lock-computer-on-ubuntu-but-with-screen-still-visible
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25:57 Random forests and the Kinect.  Used computer generated depth images to get labels for body parts automatically.  Were those derived from motion capture originally though?  

I didn't understand the randomized feature part- surely the random offsets are then stored and used thereafter in the application of the derived tree?   And the summation of the individual trees would tend to smear out the random features into perhaps something resembling a gaussian around the selected point? 
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In 2011 a milestone was reached: Apple and Google spent more on lawsuits and payments involving patents than they did on research and development of new products.
books.google.com -  Following his blockbuster biography of Steve Jobs, The Innovators is Walter Isaacson’s revealing story of the people who created the computer and the Inter...
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Have to love that system
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Currently working on underwater 3D laser scanners and various machine vision/computer vision systems.  I used to do avionics for a small aerospace company.


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