Multiple-unit train control

[3] The multiple unit traction control system was developed by Frank Sprague and first applied and tested on the South Side Elevated Railroad (now part of the Chicago 'L') in 1897.

These couplers permit trains to be connected and disconnected automatically without the need for human intervention on the ground.

In the USSR, increased capacity in public transport was necessary, but the local industry had not developed sufficiently to match world trends, such as by the production of articulated trolleybuses, the first of which was the SVARZ-TS, built in 1959 to 1967.

[5] Hence, during this period, to satisfy passenger demand, research started to produce trolleybuses connected in multiple working, which had first successfully run in Kyiv on June 12, 1966.

[6] Although other cities had tried to engineer similar systems, their solutions often resulted in rapid wear of traction motors, due to the vehicles never being intended for such use.

[5] So the invention by Veklych was borrowed by many trolleybus companies, in particular, Donetsk, Kherson, Mykolaiv, Minsk, Tallinn, Riga, St. Petersburg, Novosibirsk and many other cities.

The design of the rotating joint was similar to that of a tram with rods and hinges; both trolleybuses would have their motors and brakes controlled by the driver in the front.

[5] They also allowed for coupling and decoupling in 3–5 minutes, which was intended such that at the end of peak hours, the trolleybuses could be split again into two.

With the transition to the next generation of trolleybuses, the ZiU-682, these couplings were once again necessary for higher capacity transport, since the articulated version met constant delays.

[5] Throughout its use, the implementation of trolleybus trains have been used in Saint Petersburg, Odesa, Donetsk,[7] Samara,[8] Novosibirsk,[9] Omsk,[10] Dnipro, Kharkiv, Moscow, Kemerovo, Sumy, Chelyabinsk, Nikolaev and Krasnodar.

Two ICE 2 trains operating in multiple-unit train control in Bielefeld , Germany
South Side Elevated Railroad car #1, one of the cars that Frank Sprague converted to MU operation in Chicago
EMD F40PH Locomotive with image edited to illustrate the location and functions of the various receptacles and hoses featured on many AAR Standard North American locomotives. The communication jumpers (outermost yellow) are exclusive to passenger locomotives and are omitted from freight locomotives.
Two Japanese Shinkansen trains operating in multiple-unit train control
Two ZiU-9 trolleybuses operating in multiple-unit control in Saint Petersburg , USSR