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Category: Technical

How close are we to living on Mars? Well…maybe not so close.

How close are we to living on Mars? Well…maybe not so close.

This February was the sixth iteration of the Hawaii Space Exploration Analog and Simulation, or HI-SEAS. Since 2013, small groups of people have made this drive (up the Northern slope of Mauna Loa) and moved into the dome, known as a habitat. Their job is to pretend that they really are on Mars, and then spend months living like it. The goal, for the researchers who send them there, is to figure out how human beings would do on a mission to the real thing.

HI-SEAS is a social experiment, and the participants are the lab rats. They wear devices to track their vitals, movements, and sleep, answer countless questionnaires about their own behavior and their interactions with others, and journal several times a week about their feelings. The durations have varied, from four months to a full year, and participants come from all over the world and different fields.

However, on February 19th, the most recent experiment came to an abrupt end. The batteries powered by a solar array for the habitat lost power due to lingering clouds over the volcano. Two crew members donned their space suits, went outside, and started a backup propane generator while the two other crew members flipped a switch on a circuit breaker inside the habitat.

When the suited-up crew members returned to the habitat, a crew member was typing furiously at a computer. The other looked stricken and pale. They said they didn’t feel well. They said they had sustained an electric shock. 

It’s a reminder that even small tasks can become matters of life and death. Fortunately for this team, help was just a short drive away. Learn about the HI-SEAS program, previous missions and what went wrong during Mission Six at The Atantic via Get Pocket.

Robotic nightmare gazing

Robotic nightmare gazing

This isn’t the first video I have put up about the amazing engineering work being done at Disney Studios, but this one is definitely the most visually…unsettling.

This video describes the development of a “lifelike gaze system” for human-robot interactions. They present a general architecture that seeks not only to create gaze interactions from a technological standpoint, but also through the lens of character animation where the fidelity and believability of motion is paramount; that is we seek to create an interaction which demonstrates the illusion of life.

In its current state – it looks a little too like something right out of a Terminator movie; but I think I can see where it’s going. Imagine fully clothed (and with rubber skin) animatronics you can interact with or narrate to you at one of their installations.

IMMERSIVE LIGHTFIELD VIDEO WITH A LAYERED MESH REPRESENTATION

IMMERSIVE LIGHTFIELD VIDEO WITH A LAYERED MESH REPRESENTATION

I worked with a little bit of early lightfield photography back in the day. Looks like they’ve expanded and possibly found an interesting VR application. These researchers present a system for capturing, reconstructing, compressing, and rendering high quality immersive light field video. 

Here’s the Siggraph paper and some more examples:
https://augmentedperception.github.io/deepviewvideo/

Creating The Oregon Trail

Creating The Oregon Trail

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In 1984 I was given the assignment to help create a completely new version of The Oregon Trail. The text-based version of the game had already been around for more than a decade — but in all that time the game had never been substantially modified, much less redesigned from the ground up. But that was about to change. MECC, the publisher of the game, was ready to replace the aging product with something completely new, and I was selected to be the team leader and lead designer for the project.

Learn how R. Philip Bouchard lead the creation of The Oregon Trail we know today, but also the hunting minigame was made. Fascinating stuff.

https://medium.com/the-philipendium/designing-the-hunting-game-for-the-oregon-trail-257924bdc6ae

Modern Split-flap displays

Modern Split-flap displays

Back in the day before cheap digital displays, travelers all over the world used to listen and use these wonderful displays. They were especially popular in European train stations and airports. I say listen, because I still gets waves of travel nostalgia every time I hear them updating.

They are called split-flap displays – because they consist of flaps with digits/letters printed on them that rotated until the right digit or letter is displayed.

Split Flap Display : 8 Steps (with Pictures) - Instructables

Sadly, with the advent of cheap digital, flip-discs, and dot-style displays, these old flip-style mechanical displays have mostly disappeared.

However, a few people have tried to re-create these mechanical wonders. With 3D printing, many people have made their own.

Probably the biggest/most authentic recent attempt is VestaBoard. At $2250 for a board, it certainly isn’t the cheapest version out there – but it does sound right.

TP-Link OneMesh Network configuration and speed testing

TP-Link OneMesh Network configuration and speed testing

I recently bought the highly recommend TP-Link AC1750 Smart WiFi Router when my old one started acting up and generally being horribly out of date. Modern routers have some great features.

I also have some TP-Link RE220 range extenders (repeaters). The question was – how should one set these up? There’s a lot of different configuration options.

Turns out that Behfor’s channel on YouTube has answered my questions with some excellent testing. The first video covers the RE220, the second video covers the different ways to set these up using OneMesh – and which are the best for both connectivity and for throughput.

Godbolt Compiler Explorer

Godbolt Compiler Explorer

Ever want to see what assembly code your compiler is really generating?

There are a few reasons to want to know this. Firstly is correctness. Sometimes obscure bugs can crop up when you switch from one compiler to another, from one set of optimization settings to another, from debug to release, or even from one compiler version to another.

The second is optimization. What addressing mode(s) are being used, are there data hazards that are slowing things, are simd instructions being used? Game and high performance compute companies still spend time pulling every cycle they can out of a routine.

It used to be you had to compile and then pull the executable into a debugger and examine the code. Now, there’s an online tool that can quickly do the same. Enter the Godbolt compiler explorer.

It allows you to type in C/C++ code, select from a whole host of compilers, enter custom compiler flags, then show you the generated output.

In the case above, I wanted to verify C/C++ short-circuit comparison behavior of a variable against NULL and then dereference in the same conditional. If the compare against NULL doesn’t execute and exit before the dereference, a NULL pointer exception/segfault will result. According to C/C++ rules, there should be an early out after the comparison against NULL – and sure enough – on line 8 and 9 we see the test and exit.

Anyway – it’s a neat online tool you might give a try to learn more about the assembly your C/C++ code turns into.