Nik Kantar

Friday, April 14, 2023
4 min read

Garage Detector

Every time I mount my bicycle on the roof rack on my car, I risk demolishing it on the way back home. I think I have an idea for the solution.

I love cycling, and always have. Effectively all my rides ever start and end at home, but lately I’ve been trying to ride in places not easily reachable from my apartment, so I got a fantastically versatile bike rack. The best place to mount said rack is on the roof of my compact hatchback, which is quite a common thing.

However, this is new to me, and I’m extremely paranoid about forgetting all about it and mindlessly driving into my garage. Which would utterly destroy the bike:

drawing of hatchback with bicycle on top heading toward a building with insufficient clearance

No, thank you.

I’ve used the rack only a few times so far, and each time was really nervous about this. I didn’t forget, though, and maybe I never will, but I don’t love the risk. I did a bit of research, and found the following—sadly inadequate—suggestions:

After a bit of thinking, I came to the conclusion that I need something that will definitely get my attention when I come up on any kind of problematic clearance situation, meaning the solution needs to be fairly universal and probably loud. What I need is some sort of way to detect an obstacle ahead and play a noise in the cabin.

I did some digging for out-of-the-box solutions, because I figured I’m not the only one with this problem. Surely people driving tall cargo vans or freight trucks also want something like this! What I found were mostly expensive and permanent solutions that are specific to those use cases, and not something I could easily mount + enable, and then dismount + disable.

My tendency to (over)engineer things eventually kicked in, and I started looking for hardware I could use to build something. I’m still in the research phase, but it seems that something like a good ultrasonic distance sensor could be at the root of the detection part, probably in some sort of waterproof housing and with battery power, so I can mount it on the bike’s cockpit when it’s up on top of the car. It could use Bluetooth to communicate with a different device inside the car’s cabin, which could play a loud sound through its own dedicated speaker, which would satisfy the alerting part. See the following helpful illustration for reference:

drawing of hatchback with bicycle on top heading toward a building with insufficient clearance

As I’m quite inexperienced with hardware, this is probably not a single weekend project. In fact, I’m not even at the point of fully understanding all the pieces yet, so it’s definitely a longer-term thing. That said, I’m feeling pretty good about this tentative plan, so I’m trying to give it some time, energy, and effort to move it forward.

I just hope I get to something useful without a catastrophe. D:

Tags: projects

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