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Comment by iwakura | Hacker News Reader

This is great. But it's a little discouraging to see the project only use the US Customary units considering this is a science project. I was under the impression that NASA used SI.

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It's more common than you'd think - I remember sitting in a talk in college by someone from Scaled Composites (they did SpaceShipOne etc) and they had said that they use inches everywhere.

Wasn't the conversion, or lack thereof, the problem with one of the Mars rovers some years back? The one that landed on the surface, rolled off the pad and died. I'm sure someone here knows more details about it, but I remember it being something about the teams not converting correctly/at all between the two systems...

You are thinking of the Mars Climate Orbiter crash:

https://en.wikipedia.org/wiki/Mars_Climate_Orbiter#Cause_of_...

>I was under the impression that NASA used SI.

NASA is a very large organization with thousands of different projects ongoing at any given time. For many smaller projects like this, it's really up to the whim of the project lead what unit system is used.

I think it's aimed at students, schools etc. Its purpose should be to attract people to science so it has to be less intimidating, hence the choices of the Raspberry PI or the phone app or the Xbox gamepad to control it.

It's a weird world where kids are more scared of the metric system than they are of a credit card-sized Linux computer with its guts showing.

It probably is just a matter of being used to it. In the EU we are used to the metric system, but are ok with screen or hard disk sizes expressed in inches to the point if some brand advertising offered a 1.5 meter wide screen TV most of us would look for a calculator to make the conversion, including myself. If we changed to the metric system also for TV sizes, most people would find it uncomfortable at first, but probably would adapt in months.

In my experience, Xbox controllers are actually fairly common for large robotics. It is relatively cheap to buy a controller and USB wireless dongle plus there are lots of software libraries to help interpret controller input.

My main experience being my participation two years in a row in the Intelligent Ground Vehicle Competition (IGVC). A college competition to develop self-driving rovers and "cars" (golf carts). There were around 40 teams from various colleges (several international, not just usa) and many of the teams used xbox controllers for manual control including my team.

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