It’s nothing terribly exotic. The only real mechanical difference against a typical road bike is that the main chain-ring can spin independently of the pedals on a ratchet mechanism, which allows the little motor in front of the bottom bracket to spin the chain-ring without spinning the pedals. Everything excluding the cranks is just an off-the-shelf drive-train, and you can pedal it normally.
I noticed this in my research, but it looks like these drive-trains might be specific to Shimano e-bike motors. I’m more looking for something I can retrofit generically. Do you know of any Shimano e-bike capable cassettes/derailleurs that aren’t motor-specific?
I’ve being using offline location tracking using a different app for some time now. This looked like a pretty elegant alternative, so I decided to give it a shot!
The app looks great, and very well thought through. The automation features really appeal to me (disabling tracking at home, automatically changing profiles, etc.)
One thing I wish it had was the ability to associate vehicles with trips (potentially, automatically, based on Bluetooth connections or other triggers). I like to track the category for each of my trips (car, bike, train, walk), as well as the specific vehicle (when applicable).
I haven’t tested too much yet, but it looks like you already have pretty robust trip tracking. It would be awesome if I could create a list of vehicles with types, and select a vehicle when starting a trip, or have it automatically set when connecting to a Bluetooth device.
In any case, this app looks great, and I appreciate the effort you’re putting into an open source project like this.
The implication is that if you see them before they see you, you’ll make sure to avoid them.
I installed 24.04 fresh on a new machine, and I’d say it’s more stable than 22.04, but has a lot more “weirdness”.
Positives:
Negatives:
TL;DR: it’s speed cameras
Most radar guns work a bit like a flashlight. They just blast radio waves in the direction they’re pointed, and some of those waves hit things and bounce off. The frequency of the reflection can be used to calculate the speed of the object (i.e. vehicle) relative to the observer, sort of like how you can tell if a train horn is headings towards you or away from you based on the pitch.
Photo radar is a fair bit more advanced, and can pick out individual vehicles. With traditional radar, and human operator has to visually identify a speeding vehicle, and the radar gun is just meant to be a confirmation of the officer’s observations. Photo radar makes it possible to automate the process to reduce cost, even with multiple vehicles.
I hate to be that guy, but this is true. Before you pull out your pitchforks, read this explanation.
I take a bicycle to essentially all of my local errands, so I thought it would be cool to write an app that calculates how much CO2 emissions you’ve saved based on the number of errands you’ve run by bike (by distance). I wanted to consider everything, like food intake, emissions associated with manufacturing, etc. To be clear, the exact emissions varies wildly depending on what numbers you plug in, but it almost always comes out in favor of a passenger car. This only considers CO2 emissions, and ignores noise pollution, microplastics, and other potential environmental issues.
Long story short, if the following things are true, you’ll probably release less CO2 by taking a car:
These assumptions do make quite a few concessions, but I think it’s fair to say the majority of Americans fit these criteria.
In order of CO2 emissions per mile using the same assumptions as above (lowest to highest):
This is not me suggesting cars are better for the environment overall, but it’s an uncomfortable fact that humans are wildly inefficient at converting chemical energy into kinetic energy. Just think about the fact that when you burn 1000 extra calories per day, a significant portion of those calories had to be driven hundreds of miles on a diesel truck after spending months/years being grown on a farm.
Here’s the factors I considered. Let me know if you can think of anything I missed and I’ll re-run the numbers:
Here’s some things I did not consider:
I guess the moral of the story is that being vegetarian is significantly more impactful than cycling to work (I say as a non-vegetarian cyclist).
It might, but the Pi 5 has pretty strict power requirements. The official specs reccomend 5V5A, while most 12V adapaters supply 5V2.4A (or 5V1A for the cheap ones). It’ll generally work, but customers often experience strange behavior with questionable power supplies.
Mounting the camera isn’t terribly difficult. A significant portion of USB cameras have 1/4th inch tripod mounts, which gives you a lot of options. I personally use a little adhesive GoPro mount, with a small 1/4th inch tripod adapter. That lets you securely mount it just about anywhere with a flat surface. The camera’s cable is several meters long, which means you can mount the Pi just about anywhere. In my install you have to disassemble a significant portion of the car to get to the SD card (video is typically offloaded over LAN, which is password protected).
I will say that the Pi Zero is almost certainly insufficient for video recording. In my tests, the Pi 5 tops out at about 2 channels of 720p@30fps, while the Pi 4 struggles to encode one 480p@30fps stream. I’ve been researching SBCs better suited to video encoding, like the Nvidia Jetson, but I’m not quite ready to invest in dev kits for a non-profit project when other components of the software are much more commercially successful.
I will say it’s quite a bit more expensive than a typical off-the-shelf consumer dash-cam, since you’re essentially just installing a full-blown computer. I use a Raspberry Pi 5 for the pre-made kits, which is able to record 30fps@720p across two channels (front/rear). It’ll work with just about any USB webcam. The tricky part for new users is that you typically have to create a 12V to 5V USB harness to power it from the car.
This is a bit of self promotion, but I built an entirely open-source dash-cam that excels in this scenario. Instead of recording to an SD card inside the camera, the camera is connected to a capture device installed somewhere else in the car.
It’s not perfect, but it’s very time consuming for a potential adversary to locate the video storage. It was designed like this primarily for car break-ins, but it would work well here as well.
It all runs on a generic Linux SBC, so there’s technically nothing stopping you from encrypting the SD card too.
I don’t see how using a proprietary license will help your dilema
I guess I should clarify: Predator itself is already entirely open source, offline, and self-contained. The issue here is regarding an external service that allows you to import and manage data collected by Predator. By making this external service proprietary, I would be able to host the service and regulate how it is used. By making it open-source and self-hostable, I’m giving up control over how people use it.
If you license your project under the AGPL, the code is required to be available so people can ensure that their government is not abusing the power they have lent
I’m not sure this is how that would work. The AGPL specifically guarantees users of the software the right to use it for whatever purpose they want. Assuming the government doesn’t host a public instance of the software for third-party users, they are under no obligation to share the source code. As such, they could continue doing whatever they want with it with zero oversight.
The argument for a proprietary license would be that V0LT maintains control over the only public instance, meaning it could enforce the rules each agency agreed to. For example, a university wanting to do parking enforcement could be given a 7-day license plate retention limit, and have their ALPR geofenced to the perimeter of the campus. This oversight would not be possible with a free license, hence the dilemma.
Surely someone who wants to centralize ALPR information will simply use a service that already supports that feature. It seems unlikely someone trying to conduct mass surveillance would chose to modify a product specifically designed to make that difficult when there are already dozens of services that support that natively.
dont collect it all to some central database but have everyone make their own for private use.
This is how it currently works, and it’s why I think Predator is a better alternative (as far as privacy goes) to traditional ALPR services. Everything Predator records is stored locally unless explicitly configured by the user to do something differently.
What use is it to regular people to track others licenceplates?
To be clear using the word “track” is a bit generous here. An individual user won’t have nearly enough data to have anything close to a comprehensive location history on any given vehicle. A Predator user might be able to say “I’ve passed this car 3 times in the past month” but not “This person leaves for work every day at 9am”.
Predator is designed primarily to make use of ‘hot-lists’ where only license plates in a specific list trigger alerts. For example, the US has a program called AMBER alerts, in which emergency alerts can be issued for missing children/kidnappings. These alerts often have license plates associated with them. A Predator user can add a plate from an AMBER alert to their hot-list, and then forget about it. Predator will silently scan license plates as they drive, and alert the driver if they find the vehicle. I think this is a way better alternative to government agencies covering an entire neighborhood in license plate cameras that feed everything to a centralized database.
the whole thing will likely just be taken from you by force if nothing else works
This seems unlikely to me. There are already established companies in the space who have zero issue with violating privacy (i.e. Flock ALPR and Axon). A malicious company or government entity is unlikely to willingly go after Predator, given that it goes out of its way to make mass surveillance difficult.
I suppose so, but it certainly couldn’t hurt, especially if users have to be approved, and have geofenced restrictions.
I get what you’re saying, but I figure someone who’s prepared to do that probably wasn’t someone who I was going to be able to stop from using Flock ALPR to begin with.
I guess I’ll reframe the question a bit: Flock ALPR is the dominant brand in this field, and they have shown zero desire to protect individual liberty and privacy. This latest utility I’ve been experimenting with tries to replace the functionality of Flock ALPR with decentralized private data sources, rather than massive centralized databases (which I think is vastly better for privacy and reducing government overreach). The question is: would such a product improve privacy/freedom by eliminating the need for Flock (and competitors), or just further contribute to the problem?
That’s actually something I’ve noticed working on this project. Some people have have never heard of dash-cams, let alone ones with ALPR capabilities. People who are uncomfortable with that idea are usually pretty shocked when I explain to them what the little cameras all over their neighborhoods are for.
It feels like a bit of an uphill battle trying to eliminate state-sponsored ALPR, so my hope is that providing a less invasive alternative might be beneficial. It’s certainly a tough balance.
The cat is a bit out of the bag on that one.
Predator has been several years in the making at this point, but I’ve been trying to balance limiting mass surveillance while still having a product that’s compelling enough for people to be willing to give up the traditional mass surveillance methods.
As far as the data import utility goes, that component is still private while I figure out how to handle it.
I think you might be over-estimating the power of Predator a bit. There are already companies dedicated entirely to high-end vehicle-based ALPR, as well as fixed road-side ALPR networks. Most of the scenarios you’ve listed are significantly more difficult to accomplish using Predator, since it’s inherently self contained. An individual might be able to tell that they’ve passed a specific vehicle a few times over the past few months, but they won’t be able to collect nearly enough data to “track” them.
Here’s a scenario: A driver has a Predator dash-cam installed in their vehicle. One day, the local police put out a notice asking if anyone has seen a specific stolen vehicle. The driver goes home, imports the Predator data, and finds that they have records of passing that vehicle twice over the past month. They report that information to police to help with the investigation.
The concern with this is that the ability to import data makes it possible for a coordinated organization (like a police force) to install cameras in a fleet of vehicles, and manually import that data at the end of each shift. With a larger set of information, you could realistically use Predator to track the habits of individual vehicles.
You’re bringing up many of the points I regularly consider working on this project. It boils down to the fact that this technology is widespread, and will continue to be widespread regardless of my actions. The catalyst for starting this project was when I learned what Flock ALPR cameras looked like, and noticed how widespread they were. I wanted to build something that could replace them without compromising privacy.
It’s difficult, since there’s an argument to be made for both sides. I’d argue that the existence of Predator gives an alternative to to invasive products like Flock ALPR. But at the same time, I think it’d be great to live in a world where this technology required warrants, transparency, and other oversight from the start.
Regarding the name, Predator seems to be a bit of a point of contention. As a point of clarification, Predator does way more than just ALPR. It’s a fully featured dash-cam with object recognition, deep vehicle integration, and more. In nature, predators often have sharp vision and quick reflexes, which was the main motivation. It also opens up some clever branding options. For example “Predator Apex” is the commercial side of Predator, and each preassembled product is named after a predator (Scorpion, Owl, Falcon, etc.) Additionally, other brands in the automotive/law enforcement space tend to have rather sharp sounding names as well (“Cobra”, “Dragon Eye”, “Stalker”, etc.)
Thanks for the write up! I sort of figured an IGH/belt-drive would involve this sort of complexity. It’s an aluminum frame with quick release axles, which complicates things even further. At that rate, it seems to me like a new bike would be the better option.
A local bike shop took a look at the bike, and was surprised to hear about the problem. They said they’ve never seen anything quite like it, even considering the motor. Their best guess was that the chain-line isn’t great, and that could be causing the chain snapping issue in lower gears. The cassette wear can probably be chalked up to it being a $20 cassette.
I think right now, my plan is to try a larger offset on the chain-ring to improve the chain-line. If that doesn’t improve things, I’m looking into maybe installing a 5-speed cassette with a thicker chain. This option looks promising, but I’m not 100% sure it will work with my bike: https://www.cycmotor.com/product-page/heavy-duty-drivetrain