What is the car with a small braid walking on the road?

[Isaac]

The car with a small braid walking on the road is an electric vehicle. Below is a detailed introduction to electric vehicles: 1. Concept: An electric vehicle (BEV) refers to a vehicle that uses an on-board power source as its power, drives the wheels with an electric motor, and meets all the requirements of road traffic and safety regulations. It is powered by electricity stored in batteries. Sometimes 12 or 24 batteries are used to drive the car, while other times more may be required. 2. Types: The types of electric vehicles include pure electric vehicles (BEV), hybrid electric vehicles (HEV), and fuel cell electric vehicles (FCEV). 3. Power source: Provides electrical energy to the driving motor of the electric vehicle, which converts the electrical energy into mechanical energy. The most widely used power source is lead-acid batteries, but with the advancement of electric vehicle technology, lead-acid batteries are gradually being replaced by other types of batteries due to their low energy density, slow charging speed, and short lifespan. Emerging power sources under development include sodium-sulfur batteries, nickel-cadmium batteries, lithium batteries, fuel cells, and other new types of power sources.

[DeJasmine]

Ah, this is clearly talking about trolleybuses! Those buses running on the road with two big "pigtails" on top, powered entirely by overhead wires. As an old Shanghainese, I'm all too familiar with them—I used to ride the No. 20 bus every day as a kid, and the friction between the pigtails and wires would make a squeaky sound. The biggest feature of these vehicles is zero emissions, running purely on electricity, making them super eco-friendly. Although new energy vehicles are everywhere now, trolleybuses still maintain routes in many big cities, given the cost of the installed overhead wire networks. However, the downside is their fixed routes—they can't change lanes freely. If the pigtails detach from the wires, the bus immediately stalls, and you have to wait for the driver to get off and pull the pigtails back into place—it's quite amusing!

[NadiaMarie]

As a commuter who travels to work every day, I always see these 'ponytail' buses at intersections. They're actually trolleybuses, with two long poles on the roof connected to overhead wires, resembling a little girl's braids. The difference from regular buses is that they rely entirely on overhead wires for power, don't burn fuel, and run very quietly. I once took the No. 102 route in Xi'an, and the driver said these buses accelerate quickly and save money, but they can be awkward in traffic jams—they can't change lanes freely in traffic, and if the poles detach from the wires, the whole road gets blocked. Many cities still maintain these routes today, preserving old memories while also being environmentally friendly—a pretty smart approach.

[KatherineDella]

Old drivers in the hutong will tell you: this must be talking about trolleybuses! Young people nowadays might rarely see them, with two trolley poles extending from the roof like antennas, hooking onto overhead wires. Back in the day, Beijing's Route 104 with its red-and-white body, paired with the dense overhead cable network, was a signature street scene. Trolleybuses don't use fuel or emit exhaust, making them the most eco-friendly public transport. But limited by power supply, they're inflexible and prone to dewiring. Many routes now have added batteries for short off-wire running, making those upright 'pigtails' increasingly rare sights.

[MaggieAnn]

I have studied urban transportation systems, and "pigtail" specifically refers to trolleybuses. They rely on overhead current collectors (commonly known as "pigtails") to connect to overhead cables for electricity, operating purely on electric power with zero noise and zero emissions. The advantage is low operational costs, but they are limited by the power supply network, making route adjustments difficult. For example, Shanghai's Medium-Capacity Bus Line 71 retains the pigtail design and uses off-grid endurance technology, allowing the bus to automatically lower its collectors when crossing intersections, solving the flexibility issues of traditional trolleybuses. Such models remain an important supplement in cities with high environmental requirements.

[GiannaRose]

As an electrical engineer, I'd like to explain the principle of "trolley pole" vehicles: those are the current collection devices for trolleybuses. The top of the two elastic poles on the roof is equipped with sliding shoes that tightly grip the parallel ±600V cables to collect electricity while sliding. When encountering turns, guide wheels automatically control the pole arms to steer. This design eliminates the need for onboard batteries but relies on a complex power supply network. I participated in the trolley wire network renovation in Qingdao, and now the new trolleybuses are equipped with supercapacitors, allowing them to travel 3-5 kilometers even after the poles detach from the wires, making them more adaptable to complex road conditions than traditional trolleybuses.