Invalid carriages were usually single seater road vehicles, buggies, or self-propelled vehicles for disabled people. They pre-dated modern electric mobility scooters and, from the 1920s, were generally powered by small gasoline/petrol engines, although some were battery powered. They were usually designed without foot-operated controls.
The term "invalid carriage" persists in the United Kingdom in the regulation of mobility devices for disabled people, but excludes most of the more powerful, motorised types.