1. SCOOT (Split, Cycle and Offset Optimization Technique: Green Letter Ratio, Cycle and Phase Difference Optimization Technique) is developed by the British Institute of Transportation Research (TRL - Transport Research Laboratory, 90s TRRL renamed TRL) on the basis of TRANSYT adaptive control system. Transport Research Laboratory, 90's TRRL renamed TRL) in the United Kingdom on the basis of TRANSYT developed adaptive control system, the system was successfully developed in 1975, and in the British city of Glasgow for field trials, achieved better results. In the 1990s, the SCOOT system was upgraded several times, and its latest version is version 4.4, the copyright of which is owned by TRL, PEEK and Siemens***.SCOOT has undergone more than two decades of development, and there are more than 170 cities around the world*** where the system is in operation.

2. SCATS (Sydney Coordinated Adaptive Traffic System, or SCATS for short, or SCATS system) Sydney adaptive traffic control system, by the Road Traffic Authority of New South Wales, Australia (RTA) research and development, is currently one of the few advanced urban signaling in the world. traffic control system.

3. TRANSYT system is an offline timing optimization timing control system, the full name is (Traffic Network Study Tool) "Traffic Network Study Tool", is the timing of offline operation of traffic signal control system, this method was originally developed by the British Road Traffic Research Laboratory (TRRL). This method was originally proposed by Mr. D-I Robertson of the British Road Traffic Research Laboratory (TRRL) in 1966.

Manufacturers are not really fixed, many manufacturers sell them, they are just copyrighted to a few companies. It is also possible to find an agent to consult or buy these products.