Abstract: An electricity collector device (100) for connecting a vehicle (200) to electrical supply rails (308, 309) in a conduit (304) is disclosed. The device (100) comprises a collector system (400), a wheeled enclosure (101), a vehicle connection (150) and a power cable (104). The collector system (400) comprises a retractable collector arm (401, 402) adapted to be inserted into a conduit (304) containing an electrical supply rail (309, 309), and to make electrical contact with the supply rail (308, 309). The wheeled enclosure (101) houses the collector system (400), and comprises flanged wheels (102, 103) adapted to be engageable with the conduit (304). The vehicle connection (150) is for attaching the device to a vehicle (200), allowing the enclosure (101) to move with least two degrees of freedom with respect to the vehicle (200). The power cable (104) is for connecting the collector system (400) to a vehicle (200).