A physicist rigged his pet hamster’s wheel to upload to Strava | Hacker News Reader

A physicist rigged his pet hamster’s wheel to upload to Strava

runnersworld.com

444 pointsaanet105 comments

Neat! Not to toot my own horn too much, but I put together a similar project for my cat's exercise wheel. Hackaday featured it a while back: https://hackaday.com/2023/04/02/spy-on-your-cat-to-make-sure...

His exercise routine is somewhat variable but he usually goes for a short jog a few dozen times a day. Most often at 5 am, for whatever reason.

Since the article I also built and hooked up a treat dispenser for extra motivation.

Have you seen evidence he understands that running causes treats to be dispensed and is running more as a result?

Always hard to be sure, but I think so, yes. The dispenser is only triggered when he runs either fast enough or long enough (I forget the thresholds, but it's something like 10 mph or 10 seconds). Sometimes he'll run and not quite trigger the threshold, but wait next to the dispenser for the treat to come out. When it doesn't, he'll go back to the wheel and run/walk for a much longer period.

> Most often at 5 am, for whatever reason.

Poo time?

> Most often at 5 am, for whatever reason.

Cats are crepuscular animals. They are "programed" do start at 5 AM, hunt, and go back to sleep until afternoon. Living in homes tweaked them a little, but the 5 AM thing is still strong in a lot of them (mine included).

https://www.animalhumanesociety.org/resource/cat-keeping-you...

> Sorry, you have been blocked

> You are unable to access animalhumanesociety.org

Is this because I laughed when our family dog fell down the stairs when I was six years old?

That would be an amazing and creepy track record of the website :)

> crepuscular

So not specifically at 5AM, but around twilight. In my area, and for my cats, that changes a lot between summer and winter.

Same for my chickens, which is why "automatic chicken doors" are difficult/impossible around here: It'd need to calculate sunset and sundown, and then also consider clouds and trees: in winter the sun sets around 16:30, but the low angle makes sunlight more blocked by clouds, particles and trees and such. My chickens often decide its bedtime before 16:00 already.

Sounds like something that could be solved by an ambient light sensor.

Are you crazy? Just get an LLM into the decision loop and you can obviate the need to iterate and test with a lazy human brain and instead waste a fabulous amount of energy, all while setting your project up to get some fat VC …

Light dependent resistor, opamp and relay. No digital components required.

When I did it, I closed the door at nautical twilight. The key is that you need to close the door after the chickens roost but before the nocturnal predators come out.

Yes. We used to have these. And i turned it to most conservative twighlight.

It worked most of the times, until in winter, twice, some chickens were locked out. First time I saw it in time. Second time I only found feathers the next morning and one chicken less in the coop.

While on an especially cloudy (snowy) evenings, the door would be open when it was almost pitch dark out there and I caught a fox near already.

"The Real World" is just messier than a mathematical representation can be. I use https://sunclock.net/ and have built a watchface like that for my fitbit like that. The mathematical model is perfect as guidance. But it's not reliable enough to bet the lives of my chickens on it.

The automation features in Apple Home can be set to do things at sunrise or sunset. These track down to the minute the sunrise/sunset times from the weather app data for your location.

Your best bet, if you really want an automatic chicken door, is to get a dumb one that just opens when powered on and closes (via springs) when powered off, then plug it into a smart outlet automated to turn on at sunrise and off at sunset.

I wonder if a motion sensor detector would make the last mile of it more precise, as soon as a chicken wakes up just open the doors idk (if on timeframe)

For that you need wifi and/or power. I have neither at the coop.

Most commercial automated doors work on solar + a battery.

Automated chicken door isn't too difficult; remember the goal is to allow them to come in or out, not to make them do so or wake them up, though they do get conditioned to the door opening.

I made mine to open at actual sunrise (except in the summer; I keep them in until 7am because the coop is cooler, and if let out they can get loud before my neighbors wake up) and close it at actual sunset (not civil twilight, which most people think of when you say "sunset"). Generally the door is open well after the birds are in bed, which is fine.

Aside from some dumb birds when they were younger, I've never had one locked out (and those dumb ones were trying to nest in silly places, and weren't going you come in no matter when I closed the door).

yea. I have some of these dumb ones too. After a few days I found one crawled into the pizza oven to sleep.

The site runs like a dog.

When I had cats, I couldn't leave the bedroom door wide open, because that would give them space to come running into the room and jump onto the bed (sometimes on my face) at early hours.

This is one of the great pleasures of cat ownership!

And here I can't keep them closed because they'll stick their paws under to get a grip with their claws and bang them for funsies

I recommend getting a door sweep. Although my cat got pissed we installed it and started meowing in protest! Luckily that only lasted a few days

> Most often at 5 am, for whatever reason.

It gives him time to run, shower, and drive to work

You forgot the mandatory meditation session!

And check the @#$% calendar in MS Teams or Outlook.

I love that two people independently arrived at "my pet uses a wheel, therefore I need telemetry"

Which cat wheel is that?

OneFastCat. Very pleased with it, though it can be somewhat loud when I'm trying to sleep and the house is otherwise silent!

In the Vietnamese zodiac, the time from 5 AM to 7 AM is the Cat hour (it's rabbit in Chinese)

As a former rabbit owner I can attest that around 5 am was when the theater would open, and the first thing on was always this improvised bit called “abused animal trapped forever in a cage”. Lots of special effects too, there was gnawing and rattling and stomping. When I did open the cage door, she would jump out, take a look around and happily go back to napping right there in front of the cage.

To complement the treat rewards, can you get the cat wheel to power a small pump to provide a water fountain for the cat?

Assuming the treats are dispensed after a variable amount of distance is travelled on the cat wheel (to turn your cat into a 'gambler' of sorts, thereby keeping your cat on the wheel in the hope of a treat), a water fountain with 'fresh' water should enable your cat to avoid dehydration (due to the excessive exercise, chasing treats).

Harvested energy could also power a fan for the wheel and/or a heat pad in your cat's bed.

With these improvements, those short jogs will inevitably become marathon runs.

https://en.wikipedia.org/wiki/Operant_conditioning_chamber

Mollie the Hamster, on Strava: https://strava.app.link/FMubyPjMa5b

Project: > The main parts are an ESP32 attached to a hall sensor, which I positioned close to the wheel. Using a magnet attached to the back of the wheel, this tells the ESP32 when a full rotation has completed. It gives a timestamp (and total distance) to each magnet-pass, which is stored on the network. A python script (on my laptop) then retrieves this data in the morning, turns it into a .FIT file, and uploads it to Strava through the Strava API (with a randomly chosen run title, taken from a mostly AI-generated list of options, as I needed >100). In terms of manual additions, I had to add the photo manually, and Mollie had to do the running.

More here: https://www.reddit.com/r/SideProject/comments/1v9uyq0/i_buil...

https://old.reddit.com/r/SideProject/comments/1v9uyq0/i_buil...

> Log in to use old Reddit

Yeah, that's a recent change. Probably the first nail in the coffin for it.

Try using https://addons.mozilla.org/en-US/firefox/addon/68acaf9111064... so you don't have to login

If you look at any neuroscience paper, mice will run 10k a day or more on a wheel overnight. I thought the axis labels were wrong when I first saw that type of study. It’s quite common.

10k steps is a lot for me too.

10k for a hamster will be way more than 10k steps too!

To be fair, root comment only says "mice will run 10k a day" but it isn't 100% clear what that 10K actually refers to, could be steps, could be meters.

My physics teacher always assumed it was potatoes when the SI-unit was missing

In the running context, a 10K means 10 kilometres.

That's awfully European of you, what if the mice are from the US?

Means the same thing here.

“I ran a 3.1mi this morning and I feel awful!”

No, distance events are still referred in kilometers in the US.

US runners also typically train for kilometer races at distances shorter than half marathon.

I've even seen a few 50Ks.

It's 10km, which is a lot more than 10k steps.

Not by much. A mile is 1000 paces, or 2000 steps [0]. 10000 steps is 5 miles, 10km is 6.2 miles.

Walking on flat, paved surfaces, I do about 1850 steps per mile of distance[1]. I have a pretty long inseam, so I'm not surprised that I'd be under 1000 paces. Given that roads weren't paved with concrete or asphalt until relatively recently, I'm not surprised that the Roman mile is a little shorter than our current one[2].

[0] https://en.wikipedia.org/wiki/Mile#Name

[1] Garmin watch

[2] https://en.wikipedia.org/wiki/Mile#Roman

most mice require more steps per mile of distance

So one step is a little over half a meter. That doesn't sound like a hampster's stride.

I know, god forbid someone cracks a joke on HN

I knew mice were active at night, but I wouldn't have guessed 10k+ was routine

My hamster broke his record with 22k revolutions on his 10” wheel a few nights ago. That’s about 11.5 miles.

That’s much higher than usual, but when they want they can go.

what if you put a screen so it has a full simulator in the wheel

Also cats - I saw experiments where they gave the “my cat is mostly sleeping and sometimes wandering around the garden” cats gps tracker, and found out they routinely wander 8 km away into the woods each night.

This is amazing and I love it.

I was surprised that the owner said he needed to get a Strava premium account in order to be able to auto-upload the hamster's activities. Not 100% sure why.

He might be able to use https://github.com/dlenski/stravacli (written by me) or the library it's based on (https://github.com/stravalib/stravalib) to avoid this requirement and save a few bucks.

That would be pretty funny if the hamster ended up with Premium purely because of an implementation detail

Reminds me of Nobel and Ignobel prize winner Andrei Geim, who authorer a paper with his hamster, H.A.M.S. ter Tisha. As I remember, he added Mr/Ms Tisha to be able to write “we” instead of “I”.

https://www.sciencedirect.com/science/article/abs/pii/S09214...

I thought in papers the majestic we was just a given even for solo writers I guess depends on the OCD of one if thats acceptable

Also built a bike computer for my daughter using an esp32, reed switch and magnet.

As we had recently watched Back To The Future, when she reached 8.8 mph it would play a brief snippet of appropriate music!

That’s amazing, nice work Dad.

Do you also play the approach music when her power output reaches 1.21 Gigawatts?

Should probably scale it appropriately like the speed

1.21 hundredwatts?

1.21 hectowatts.

We are all hamsters on Strava.

The only difference is the hamster doesn’t pretend the morning run was enjoyable

Many runners do enjoy running.

Like every sport, it’s not for everyone. If you don’t enjoy running you don’t have to do it.

I personally find the easy runs relaxing for the brain, and not taxing on the body, and the hard runs are quite fun.

Most sports have a habituation threshold you need to overcome so it becomes an enjoyable habit. Running is probably one the steepest imho.

Gym is the steepest. Three years in and I still hate it.

Each to their own, but I think free weights is the easiest activity where you get to feel tangible progress from doing it.

You move weight around, later you move the same around a bit more (yay!), or move a heavier weigh around (yay!).

You get to really know what your body is capable of.

I love this. I feel like there’s a business and/or product line here if it doesn’t already exist (hamster habitats with integrated cameras).

It does! Sort of.

The company Niteangel sells a pedometer for their hamster wheels. It doesn’t provide times or speeds, but it does give you the number of revolutions per night.

I have thought it would be interesting to hook something up to be able to get the times and speeds. It never occurred to me that you could use something like Strava to record it.

> my hamster now has Strava Premium

Somewhere there's a product manager looking at this and adding "multi-species household plan" to the roadmap

Let the user choose between "run", "bike", "swim" and "ferris wheel"

the hamster averaged over 10km/night!! given the size of the animal I would not have imagined anywhere near that.

Various people have tracked their pet's movements, and that's genuinely a really good thing to do to understand whether they're getting enough activity. But to Strava it and create competition among pet owners, very interesting.

I wonder if one could calculate the watt-hours produced in a day by a theoretical 100 hamsters on generator-attached wheels, and if you could run a laptop and LTE hotspot from that (or similar load).

An infinite number of hamsters running in an infinite number of hamster wheels could power a datacenter for one day.

An infinite number of data centers even!

A smaller infinity, but still infinite.

No, they would collapse into a singularity with an infinite event horizon that eats up the universe at the speed of light

So, an infinite speed, you say? ( ͝סּ ͜ʖ͡סּ)

Unless you're using miniature giant space hamsters

Make the data center run ML/AI experiments for how to effectively run a "energy generation hamster farm" and you have a completely grid-and-internet independent energy solution that optimizes itself via hamsters over time.

Isn’t this uncomfortably close to the premise of the Matrix?

As long as we don't drug the hamsters and jam them into some sort of fake digital world, we should be fine? Put OpenAI's security researchers on it, heard they're good at containing experiments.

Reminds me of the universal paperclip thing. AI harvesting matter for more hamsters.

But make sure the ML/AI knows how to predict the quantity of bulk grain supply that will be needed to feed the hamsters, and supply long term delivery contracts.

A quick search suggests one hamster can produce around 0.5 Wh/day, so 100 hamsters should easily power your phone laptop with a constant 50W!

That would be an average supply of just over 2 W. (50Wh/day is 50Wh/24h or 50/24 W)

You're right. Wh/day is a terrible unit!

Dupe of link to original post on reddit: https://news.ycombinator.com/item?id=49216926

I’m not surprised. If my hamster isn’t sleeping, he’s running on his wheel. I’m starting to think he’s having an existential crisis...

Bipolar

Would a hamster run this much naturally? Or is the running because of the boredom of captivity? TikTok for hamsters?

“eat-sleep-run-repeat" -- relatable.

thats roughly the equivalent of a marathon (or a bit under) a day for a human

Gonna want this in steps.

Depends on the situation imo

Dude named his hamster Mollie, but refers to it by “his” and “he.”

Must be Dutch humor.

> Over one seven-day stretch, he started within the same 10-minute window on five nights, between 9:54 and 10:04 p.m.

I wonder if this correlates with Thijs's bedtime schedule, or if the hamster really is that precise.

We feed the cat at home at the same time every day, and her internal clock definitely know when it's time less than 30' divergence. She suffers the daylight transitions immensely too because of this.

Every year when DST transitions out, I say “next time we should move the cats’ dinner time gradually leading up to it”, but never remember. I now have reminders for the 5 days leading up to move it later by 10 minutes a day. I don’t know if it will actually make a difference

Now the real interesting part would be if people can find a way for their hamster on strava to leak the locations of not-publicized military activities.

https://www.google.com/search?client=firefox-b-d&q=strava+le...

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