johnwalkr (u/johnwalkr)

johnwalkr commented on The History of F1 Design espn.com/espn/feature/sto... · Posted by u/anonyonoor

brightball · 20 days ago

Wow, I read your comment before I clicked. What were they thinking.

I’ve been getting into F1 this summer since the movie got my interest up.

johnwalkr · 20 days ago

If you live in a region where F1TV is standalone (eg: US) and not part of an expensive sports package (eg: UK) it's good value. You can watch old races and related content, and each race weekend there is a good 4 hours worth watching live (qualifying and race, with good pre/post content). You can open multiple streams with the main race footage, any driver's live on-board video and radio, and various screens of telemetry. It's worth watching on a mobile device even if you are at a race watching live from the stands.

johnwalkr commented on Designing a flatpack bed kevinlynagh.com/newslette... · Posted by u/todsacerdoti

recipe19 · a month ago

I hate to say this, but it seems like a pretty clear case of using the wrong tool for the job.

There's no conceivable reason to cut something this simple on a large-format CNC mill. It's literally just a couple of straight cuts. It's not going to be faster (not with standard endmills), not going to be easier, and it's not going to be cheaper unless you're making them by the thousands.

You can likely buy S4S lumber for less than an oversized sheet of furniture-grade 1" plywood.

johnwalkr · a month ago

If the machine is available and it’s a hobby project it’s ok, but you’re right this is not a cheap or easy way to do it.

But as a mechanical engineer, the whole project is such a “software” approach to me, starting from turning the selected tool into a requirement to use. Then, rather than just powering through in solidworks for a one-off design, the author spends a lot of time looking for automation tools like they are a library, points out this approach feels like coding in rust, gives up, and even blogs about it.

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

crabbone · a month ago

https://youtu.be/yKQBR1ohtIA I mean this. Whatever's the proper name for it. The video makes it look easy, but the reality of it is that

* Spokes don't really fit into the hole (and you aren't really going to pull a spoke out of the wheel to take the wheel off anyways). * Adjusting the tension on the cable takes many tries. And you can't really adjust it without taking the wheel off. So, you put it together, try riding it and see if the speeds switch properly. Once you see they don't, you take the wheel off, pull the cable a little bit. Rinse and repeat.

Not to mention that the parts are very small and easy to lose if you have to make an emergency repair. It's very sensitive to dirt.

It looks more "compact" and out of sight, and from what I can tell from talking to my Dutch friends / acquaintances: punctures don't happen that often because roads are kept relatively clean. And people would generally just go to a bike shop and pay to have things fixed. So, decreased reliability and difficulty in maintenance don't bother them.

johnwalkr · a month ago

That's an "internal gear hub". It also takes some practice to do it quickly. In the video a small hex key is used to rotate it, not a spoke. You shouldn't need to adjust tension after re-install more than a couple of clicks on the barrel adjuster. If you do need to adjust at the hub, it does take practice which you normally won't get doing it only once per year..

They have a few advantages (basically zero maintenance over the life of a bike, can shift when stopped, easy to fully enclose entire drivetrain) and disadvantages (heavy, expensive, less efficient, can't shift under load, pain to remove wheel) compared to derailleurs.

They're nice for commuter bikes because you can fully enclose the drivetrain, keeping rain off the drivetrain and grease off of your pants and never need to be touched, until you have to remove the wheel, as you found out. Overall I think they make sense for that kind of bike.

johnwalkr commented on Origami Space Planes Could Solve a Major Problem in Orbit gizmodo.com/origami-space... · Posted by u/Bluestein

ashton314 · a month ago

I wonder if having a big origami paper sail that unfolds as the satellite nears EOL would increase drag significantly enough to help the satellite de-orbit faster. How does de-orbiting usually work anyway? Shoot a thruster in the direction of travel and slow down?

johnwalkr · a month ago

De-orbiting at a low orbit is often showing that without fuel and commanding, the satellite's orbit will degrade and it will burn-up within a few years (or even 25 years) due to the very minimal drag of the atmosphere that exists to some extent to thousands of km. Deliberately moving down faster is common, and deliberately moving satellites very far away to a "graveyard orbit" is also common.

Deploying sails to increase drag has been tested a few times in real missions, and is a common theme for university satellite projects and space-industry start-ups.

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

crabbone · a month ago

I'm with you on this!

Here's a bit of a marginally related rant.

So, I moved to the Netherlands about four years ago. Of course I needed a bike. Since I was a child, I always fixed my bike if there was a problem. I've replaced punctured tube countless times.

Yet, in the Netherlands, I discovered that on the local bikes the gear box is a lot more complex... and you need to disassemble it in order to remove the back wheel (if you want to replace the tube). It doesn't have that many moving parts, but it's really not made with an eye for easy assembly and disassembly. Not in the field conditions. And the first time I discovered it, to my shame, I ended up pushing my bike to the bike shop to have the tube replaced. I felt like I was telling the shop owner that I peed my pants when I had to ask him to do something that should've been trivial for an adult.

I can't imagine using a wireless gear box. I'll never get on this kind of bike. Some kind of interference and you lose control of the bike? Broken far away from home: push it for hours? This thing probably needs a battery... Is it waterproof? This is such an unimaginably bad idea...

johnwalkr · a month ago

By gear box do you mean the covered system between the bottom bracket/cranks and the rear wheel? Dutch commuter bikes are usually one speed and that system keeps grime out of the chain and keeps your pants clean. It is indeed a PITA to remove the rear wheel on these bikes (especially the first time), although you can often patch a tube in situ without removing it completely.

This product does not replace that system. It is for very high-end bikes with owners. These bikes still have a chain that runs front to rear, it only replaces the derailleurs. If it fails or the battery dies, you're stuck in one gear but you don't have to push your bike. And you can manually change gears if you really need to. Yes it has a battery, yes it's waterproof.

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

doctorpangloss · a month ago

In terms of maintenance, most cyclists would benefit more from internal gear hubs and carbon belts. From a product development POV, seems better to make auto shifting IGHs. Indeed this is how share bikes are designed.

johnwalkr · a month ago

That's long-term maintenance for commuters and casual riders. This product is for competitive and serious riders, and it reduces another type of maintenance (setting up and maintaining their bike for high performance).

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

topaz0 · a month ago

What ever happened to measuring speed, cadence and pedal force using your body and mind?

johnwalkr · a month ago

Well speed is something a large portion of cyclists have always wanted. Adding a cycle computer or even a mechanical speedometer in earlier times was always popular. Now GPS units and smartphone mounts, or just logging your ride in an app using your phone or smartwatch are popular.

Cadence and pedal force are very useful for training and competition (organised or the self-improvement kind), so pretty much for the same cyclists that would also want wireless shifting.

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

wil421 · a month ago

I’d take a wireless dropper post so I don’t have to mess with cabling.

johnwalkr · a month ago

I'm also thinking of one. They exist and allow greater extension for the overall length and/or greater nominal adjustment compared to internally routed ones because no space is required for the cable. This space is significant once you consider minimum bend radius.

johnwalkr commented on MakeShift: Security analysis of Shimano Di2 wireless gear shifting (2024) usenix.org/conference/woo... · Posted by u/motorest

crabbone · a month ago

A wireless (electronic) device simplifies the setup? What kind of insane fantasy is this? Will you really be able to fix your broken wireless gear box in field conditions? This is the proof of simplicity, not some superficial observation that you make about the amount of cables.

johnwalkr · a month ago

It simplifies installation and getting a reliable, comfortable shifting setup, yes. Installation is simplified, especially in the case of internal and headset routing, which is something the target audience would deal with in case of cable-actuated derailleurs. Changes requiring adjustments over time due to the cable wearing out or stretching are eliminated, simplifying maintenance, both during and in between rides. On drivetrains with front and rear derailleurs, it has an optional adjustable algorithm that shifts both together for you and chooses the best gear combinations as you press up and down, simplifying operations. Auto-shifting is available on some models. There's more possibilities to put the shift buttons in the most ergonomic place, or even put them in more than one place, simplifying setting up your bike for comfort. That it doesn't simplify fixing your derailleur in the middle of a ride doesn't negate all of its benefits. Yes, the radio or battery could fail, but on the other hand it is less prone to go out of adjustment.

Also it has one killer feature and everyone that tries one also raves about how well it works. You know those little ramps stamped into the side of the sprockets on a cassette, that the chain moves up and down on as you change gears? Di2 delays your shift precisely until the start of a ramp, which makes shifting faster and works much better under load. That crunch and possible stuck chain when you shift to start a climb is basically eliminated.

Is it something a bikepacker will choose? Probably not. Is is something attractive to many other types of cyclists and simpler to install, use and maintain in ways they care about? Yes. I'm a weekend mountain bike rider, not at all competitive. I personally won't get one because of the cost but the features are quite attractive to me, while the risk and consequence of a dead battery seem low. There are many, many other things that are more likely to break during a ride, many of which will have you walking back. A dead Di2 battery means you are stuck in one gear, and if your chain has a master link or you carry a chain tool (target demographic definitely has one or both) you can change the gear in 2 minutes.

I thought of an analogy for HN. Think about water cooling in a gaming PC instead using the stock CPU cooler. It's more expensive, but generally higher performing and quieter and arguably looks cool. There's a certain demographic who thinks they are stupid because they must have extra parts so which are difficult to install and must be less reliable, and they may have one horrible failure mode of leaking liquid inside your PC. They might give the example of a mission critical server, and be right for this use case that it's not a good idea, at least at the scale of one machine. There's another demographic who don't think twice about buying them because the positives easily outweigh the negatives for them. This group can sometimes be seen telling the other group that they are out of date on it being difficult to install (you can even buy a case with it pre-installed) and reliability (modern all-in-ones almost never leak). They will most likely concede that for a mission critical server it's not the correct product.

johnwalkr commented on Bento: A Steam Deck in a Keyboard github.com/lunchbox-compu... · Posted by u/MichaelThatsIt

johnwalkr · 2 months ago

That's really cool. I don't think you should support another keyboard, there may be better ones from a certain POV but I don't think there's a better one that's not significantly thicker and any keyboard options will quickly multiply complexity with any SBC/computing options. You will go down a rabbit hole if you start taking requests here. I think steamdeck internals plus rpi5 plus latest framework internals with no other configs is ambitious but not too ambitious.

My hobby is miniaturizing everything. If I were to fork this project (and I would love to after about 10 other projects are complete), I would think about selecting one good dongle, "shucking" it any other needed things, integrating them, and then finding the minimum volume to fit my preferred travel controller[1] and preferred travel mouse[2]. Then, I would consider customizing the housings of those things to be even slimmer without customizing any electronics except for maybe making sure everything gets charged while stowed. I would also consider minor mods to the keyboard to get rid of the bulk of the usbc cable. Pogo pins plus some 3D printing should do the trick.

[1]https://www.youtube.com/watch?v=55DO1HDeCHQ. No longer available new but this is the only good slim dual analog controller I have found.

[2]Still looking for a good one