Okay hear me out: an electric autonomous untethered bike trailer, which completely controls itself, BUT it does this by following a visual tracker panel. The trailer's computer controls the brakes, motors, and rear lights, using input primarily from a camera mounted on the front.
Why does it need to be autonomous? To be untethered. Both it being electric and it being untethered mean that the cyclist leading the trailer doesn't have to actually tow the trailer, which makes cycling with it as easy as it is without it.
I'm not sure whether the camera should have a fisheye lens or not. It will probably need a rain shield above it and have the right lens to make out the tracker dead-on from somewhat above whatever the safe stopping distance at 28 mph is (123 feet, apparently).
The tracker would be a plastic equilateral triangle (maybe with the corners chopped?), with a white, or maybe yellow, reflective fill on one side, and some shapes marked on it to help identify the perspective and distance (and to identify the tracker). The reflector would probably need to reflect infrared light as well, so that the trailer can use an infrared light if it's dark, so it can still see the tracker. The tracker might also have an RFID tag in it, which the trailer could use to make sure it stays following the same tracker. The reflective face would have two black, non-reflective filled circles inside the bottom corners, and a similar triangle or square inside the top corner. This pattern would be recognized by the controller (via the camera, of course).
If it sees the tracker moving farther away, it speeds up to catch up to it. If it sees the tracker moving closer, it cuts off the motor and applies the brakes as much as necessary to slow down or stop (based on the speed it's coming at it and how far away it is, which is judged by the size on the feed).
It would need to use perspective to figure out if it needs to turn or not. So if it sees the triangle at an angle, with the left side farther away (smaller) than the right side, it turns right (at some proportion to the ratio of difference). And vice versa. It turns at a delay based on the stopping distance, which is in turn determined from a fixed algorithm based on speed.
Maybe it would have an on-board compass or something to determine when it has turned 90 degrees? So if it loses tracking during a turn, it would keep turning until it reaches 90 degrees then straighten out, cut the motor, and scream until it starts tracking again.
I'd like it to have a car-like light setup on the back at the top of the box, with a tall rectangular panel on both corners (and around the corner, half as wide). From the back, I'd have it with a square of red lights, maybe a thin line of turquoise lights, which are solid on while the trailer is tracking (and fade off during the lost tracking grace period) to indicate that the trailer is operating autonomously. The bottom third or so would be mostly amber turn signals, which when used as a turn signal would "wipe" on and off from the center, but there would be a thin triangle slice closest to the center of the trailer which would be white lights, which would really just flicker to make the trailer visible.
The "lost tracking grace period" is about 1 second, so that in case, say, a bird crosses in between the bike and the trailer, it may lose tracking for a brief moment, and it can get it back again. Once that grace period expires, it starts making some kind of chime or alarm to let the cyclist know they have lost the trailer.
While it is at a stop, the trailer will make sure there is at least a 1 foot gap. If the cyclist starts backing up, it starts backing up, maybe reverse-beeping, the white lights come on solid and the hazards automatically come on (temporarily overriding the setting)
It would have two (or three?) removable bike batteries underneath the box, released from the same side. The deadbolts on each slot would be controlled with one keyhole, probably on the front. They'd be distributed so that there's one in the front, maybe one in the middle, and one in the back. You don't have to put all of them in there; in fact, it wouldn't ship with all of them in a standard model (probably only one; and two empty shell slots).
Inside the box, at the front, behind the camera, that's where the battery gauge lights would be. Two (or three) numbered battery icons at the top, which would light up green if they have battery, red if it's empty, and off if there is no battery inserted in that slot. Then four dots beneath each to indicate battery level. When it's in motion the dots will turn off, but the battery icons would stay lit. If the last battery has reached 2 "bars" it'll ding, and then once it's down to 1, it would start chiming every so often to remind the pilot that the batteries are low.
I'm not sure how the battery use would be distributed. It could be that it uses them in order, or distributes the load between all of them, maybe proportional to how much each one has. Maybe both depending on use: normally, it'll use one battery at a time in order of whichever one has higher capacity, switching when the battery capacity goes down to 1 "bar," and if it needs more power to maintain speed (maybe because of how much weight it's carrying) it'll pull from other batteries too.
I think I'd do it as a trike, with two wheels on a motorized axis in the back and one in the front to steer. Or put the motor in the front, like a hub.
It might have manual stabilizers in the front, but ideally when they're put down the motor doesn't activate, and if it detects you're pulling off without it, it'll make some audible chime at you, so it doesn't drag the stabilizers along the ground as you go. It might also chime at you if it loses tracking for longer than, say, a second.
It would be built to be compatible with any bicycle, but not anything faster than a Class 3 e-bike -- so the motor tops off at 28 mph. It would then use the brakes to go no faster than 32 mph and probably make a chime about it.
It'll still try to keep distance if it detects a roll-over of the leading vehicle.
...It would probably be totally ineffective on hard shoulders, where they crumble away and go right into the ditch... it might need some detection to avoid that... It wouldn't be a problem if the leading vehicle were wider than the trailer. But the trailer is wider than a bike, and the paired rear wheels make it not as nimble as a bike, either. But isn't that the case with any trailer?
It could also expose USB port(s) on the front (inside?). It could be kinda cool to have an NACS, J1772, or CCS charging port on it, which could potentially also be used to charge the pilot e-bike somehow (probably a wall-outlet port, but does the EV port give it enough power?). I think it might also try to power USB devices directly from the EVSE port, and only report that it's "done" when any USB devices aren't really charging anymore.
If it has a wall-outlet port, it would only work while it's being charged. The slot for it might also only unlock while it's plugged in, it would have some springs or something to try to close it when there's nothing in the way, and it would only lock again when it's closed. That might help prevent people from trying to use it as a backup battery, which the e-bike battery packs are not designed to do in the least.
It could also have a disturbance-alarm system built in. Maybe also a secret slot, both locked by the battery key and screwed shut, which would be a great place to hide an AirTag. If it's got USB ports or a wall-outlet port, plugging in or removing devices while it's locked would also trigger the alarm. (But it would continue to charge any devices that were plugged in before it was activated.) While the alarm is armed, it could even try to lock up the wheels. It would probably either deadbolt the power switch or simply not respond to it, so that it has to be unlocked to power off (because otherwise, it's a brick with no alarm system).
Getting it to be street-legal might be the biggest hurdle here: it's autonomous, it can have multiple batteries, and there isn't any legislation allowing this type of vehicle. Now, I could probably get away with R&D on private property (i.e. in the parking lots at Wake Tech, with permission I could possibly get), but it would not be legal on public roads whatsoever...
A few models of this concept might include:
- One where there's a seat and backrest in the back. Maybe a seat in the front, too.
- One where the back can be taken down like a tailgate of a pickup truck.
- One that folds out into a picnic table. (Maybe it has the sides fold down and the base lift up? So the sides would be the seats and the base would be the table. And you can still use it to transport your food and stuff!) ...maybe not this one though, it's pretty damn complicated
- A four or six passenger version which would be kinda like a hayride where it puts the passengers facing the sides and their backs facing each other. Seatbelts and sidebars included so you don't fly off the back. Potentially shaded (this could be an option, or come standard, and/or be removable or replaceable... Maybe solar panels that can also trickle-charge the batteries 😻).
- One with a locking cover of some kind (shed door like, maybe? or a sliding cover like the Cybertruck or like a garage door? or one big door? It could be solar, maybe, but eh probably not)
I think it would be funny to see this, particularly the passenger model, set up to follow an RC car with the tracker rigged above the top of it with some poles.
And you absolutely could chain them together, like a little train, by mounting a tracker on the back of another trailer.
This would be great with a wireless (and maybe wired) bicycle turn signal protocol -- which I'd seperately really like. A paired, authenticated protocol in the 2.4GHz spectrum, which can control different devices' light modes, and (most importantly!) synchronize so that you can have one on the front, one on the back, and even one on your trailer!
