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Can you instruct a robot to make a PBJ sandwich?

https://pbj.deliberateinc.com/
17•mooreds•2h ago

Comments

GianFabien•1h ago
What's the point? No matter how detailed and comprehensive the instructions and steps by the AI, you still don't get a PBJ sandwich to eat. You have to go to the kitchen and do it yourself.
t-writescode•1h ago
It’s a reference to a famous YouTube video[0] about how to write instructions that can be followed.

One of the most important things a programmer needs to do is learn how to tell a computer how to do something. It’s a surprisingly hard skill because each step is way more complicated and has way more variables to go through.

https://youtu.be/FN2RM-CHkuI

ksaj•1h ago
I saw a YouTube Short of a teacher demonstrating this to her young students. Of course the kids are laughing lots at the results of her literally enacting their instructions and exaggerating the missing necessary info. But I bet they came out with a far more technical thought process.

This should be part of the curriculum.

parpfish•1h ago
i once had this "make a PB&J" as part of a written take-home interview.

i knew the schtick -- no matter how precise and complete you are, there is always the possibility for another little gotcha. and that makes it absolute rubbish for a take home because... how much detail do i need to go into to satisfy the manager reviewing this? i think i wrote a couple paragraphs and ended with a little rant about how i know how this problem works and it'd work better in person. i don't know how much they expected somebody to write.

Benjamin_Dobell•1h ago
Although this is a facetious take, instructing a robot to follow recipes is a fantastic introduction to coding. I added a visual scripting layer to Overcooked so kids can program robots to make all sorts of dishes (Sushi, Pasta, Cakes etc.)

https://youtu.be/ITWSL5lTLig

This is part of a club to teach kids coding, creativity and digital literacy.

jgable•1h ago
It’s funny, when I’ve seen this demonstrated, it’s basically literally impossible to get the right result because the test maker doesn’t define an instruction set that you can rely on. They will deliberately screw up whatever instructions you give them no matter how detailed. A computer has a defined ISA that is specified in terms of behavior. A compiler transforms a language with higher level abstractions into this low-level language. I’ve never seen this “test” done with any similar affordance, which doesn’t really teach anything.
totallymike•51m ago
Oh I think this lesson teaches quite a lot. Maybe your instructor is deliberately screwing up, but perhaps other end users are just not paying attention, or are missing assumed knowledge, or are feeling particularly adversarial on the day they need to follow your instructions.

One of many lessons that can be taken away from this exercise is to understand your audience and challenge the assumptions you make about their prior knowledge, culture, kind of peanut butter, et deters.

void-star•1h ago
It’s almost like we need some deterministic set of instructions that can be fed to a machine and followed reliably? Like… I don’t know… a “programming language”?
nomel•47m ago
I would say that's exactly not the solution, since the surface area is too large to hard code (which is somewhat the point of this). Evidence being, it's 2026 and there are exactly 0 robots that can do this simple task reliably, in any kitchen you put it in.

You need something general and flexible, dare I say "intelligent", or you'll be babysitting the automation, slowly adding the thousand little corner cases that you find, to your hard coded decision tree.

This is also why every company with a home service robot, that can do anything even remotely complex as a sandwich, are doing it via teleoperation.

squeaky-clean•1h ago
When I was about 7 or 8 years old, my elementary school music teacher did this same exercise with us, except the goal was to draw a musical staff and the first 3 notes of Jingle Bells (or something along those lines). I can still remember how much fun I thought it was.
LeoPanthera•59m ago
Demonstrations like this are a regular feature of the Japanese educational TV show "Texico", which teaches logical thinking with the specific goal of preparing young children for programming.

I highly recommend it. It's extremely well made, and quite entertaining even for adults.

It's available in English, 10 minutes per episode, no subscription required:

https://www3.nhk.or.jp/nhkworld/en/shows/texico/

userbinator•41m ago
Texaco + Mexico = Texico? The Japanese never fail to amuse foreigners with their naming.
ljlolel•31m ago
Texas?
fghorow•53m ago
As always, there's an XKCD [1] for this!

[1] https://xkcd.com/149/

notsylver•40m ago
This feels like a buzzfeed quizz for developers. If you think about each step long enough you can't really get a wrong answer
aryehof•35m ago
There is an alternative to describing the (subjective) “process”. That is to describe a model of the sandwich - the parts and how they can collaborate. The issue is that how to do that is forgotten and unfashionable.
jbritton•28m ago
It’s kind of interesting relating this to LLMs. A chef in a kitchen you can just say you want PB&J. With a robot, does it know where things are, once it knows that, does it know how to retrieve them, open and close them. It’s always a mystery what you get back from an LLM.
jbritton•22m ago
Also true of specifications. Anything not explicitly stated will be decided by the implementer, maybe to your liking or maybe not.
mjevans•7m ago
I'm reminded of wish-granting genies, and then of 'undefined behavior' and compilers...
gormen•23m ago
Of course, we need to give the robot a cognitive architecture so that it understands the task, the context, and corrects its actions, and then it will autonomously make such sandwiches every morning for breakfast.
dang•21m ago
My "related" past threads fu is failing me right now but I know there have been several threads with this theme in the past, including the video with the dad carrying out his kids' literal instructions in a cute but also borderline uncomfortable way.
gnabgib•12m ago
PB&J AI (3 points, 1 year ago, 2 comments) https://news.ycombinator.com/item?id=42222009

Dad Annoys the Heck Out of His Kids by Making PB&Js Based on Their Instructions (2017) https://news.ycombinator.com/item?id=13688715 https://news.ycombinator.com/item?id=41599917

& infamous: sudo make me a sandwich (2009) https://news.ycombinator.com/item?id=530000

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Can you instruct a robot to make a PBJ sandwich?

https://pbj.deliberateinc.com/
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