ACTIVATE SIGNAL TRAFFIC CONTROL SYSTEM

Abstract: It can make a distinction in conformity to traffic request. The system is made up essentially of a microcomputer formed by a central processing unit (3), by a program memory (4), and by a data bank, all receiving control parameters through a keyboard input assembly (7) or data transmission system (8). The system is very flexible in coordinating urban traffic to the extend. It can be adapted to various traffic plans and timetables through a program memory (4) and peripheral elements. It can operate centrally by the simple installation of a communication system between ten central and a local control system. This permits the application of a traffic control plan by areas. When operating at periods of low density traffic the system gives right of way with minimum waiting through the central processing unit, the phase assembly, and the phase module interface (6). It permits, moreover, synchronization between various identical control systems through an external synchronized clock without being physically connected to the control system.

Description: ACTIVE SIGNAL TRAFFIC CONTROL SYSTEM THE ABOVE INVENTION IS A COMPUTER COU TROLLED TRAFFIC CONTROL SYSTEM ACTIVATED BY THE ACTUAL FLOW OF VEHICLES. BEI G WHICLE ELECTRONIC THIS EQUL£ MENT IS OF GREATER RELIABITY THAN THE ELECTROMECHA ICAL TRAFFIC CONTROL SYSTEMS. AIMING AT INCREASING THE AVERAGE TRΛ FIC SPEED, THE EQU IPAMENT, USING SENSORS AND COMPUTER LOGIC, MINIMIZES THE NUMBER OF STOPS AT INTERSECTIONS AND THE DURATION OF EACH STOP ACCORDING TO THE SPECIFIC REEDS OF EACH INTERSECTION AND THE HOUR OF THE DAY. ESSENTIALLY THE ACTIVATED SIGNAL TRA£ Fie CONTROL SYSTEM (HEREINAFTER CALLED "THE SYSTEM") IS MADE UP OF A MICROCOMPUTER APPLIED TO A SYSTEM OF PHASE MODULES, SENOR MOOULES, KEYBOARD NODULE, ELECTRICITY l_\ PUT MODULE AND CIRCUIT INTERFACE MODULE. THE MICROCOMPUTER IS COMPOSED OF A MJ. CROPROCESSOR, WITH A PROGRAM MEMORY, DATA BANK, CONTROL CIRCUIT, AND SWITCH CONTROL. THE SIGNAL PROCESS IS COM PLEMENTED THROUGH COMMON SWITCH TECHNIQUES. COMMUNICATION BETWEEN THE MICROCOMPUTER AND THE VARIOUS MODULES IS CARRIED ON THROUGH SPECIFIC INTERFACES, AS FOLLOWS: A) SET OF PHASES FOR THE INTERFACE OF PHASE MODULES. THIS CIRCUIT PERMITS THE COMPOSITION OF A PHASING MATRIXj IT RECEIVES IMPULSES FROM THE l OMPI Λ. WIPO « CROCOMPUTER, OECOOIFYING THEM, AND SEOING A COMMAND 1 PULSE TO THE MODULES FOR THE DISPLAY OF THE APPROPRIATE TRAFFIC LIGHT: GREEN-YELOW-RED OR GREEN-RED INTERMIX TENT-RED. B) SET OF SENSORS FOR THE INTERFACE OF SENSOR MODULES, PROVIDING THE COMPUTER ADDRESSES OF EACH VEHICLE SENSOR OR OF A PEDESTRIAN AS ING FOR THE RIGHT OF WAY. A PULSE GENERATOR CONSTANTLY CHARGES A BINARY COUNTER, WHICH OUTLETS AREA CONNECTED TO CIRCUITS THAT SWEEP ALL SENSOR MODULES. WHEN ONE OF THE SENSORS |S ACTIVATED A COMMAND IS SENT FOR THE PULSE GENERATOR TO STOP AT A POINT CORRESPONDI G TO THE PHASE OF THE SEϋ SOR. c) KEYBOARD SET FOR THE IMPUT OF co-ϋ TROL PARAMATERS. DATA ARE INTRODUCED BY DIGITAL KEYS AND ARE ASSOCIATED TO CONTROL TO CONTROL PARAMETERS THROUGH THE SWITCH KEYS OF A BINARY COUNTER THAT IS ALWAYS ON. WHEN THE SWITCH KEYS ARE OFF THE COUNTER sτ-fi PS, SUPPLYING THE ADDRESS WHICH CORRESPONDS TO THE ACTJ. VATED KEY AND THE RELATED CONTROL PARAMETER. D) THE OUTPUT SET DECOD IF IES THE SIGNALS SENT BY THE MICROCOMPUTER AND SHOWS THEM IN LETTERS AND NUMBERS. THE SYSTEM PRESENTS THE FOLLOWING ADVAU TAGES: I) IT ALLOWS GREATER OPERATIONAL SPEED OF BUSES RUNNING ALONG EXCLUSIVE LANES. SENSORS AT THE INTERSECTIONS ARE PROGRAMMED TO ALWAYS GIVE THE RIGHT OF WAY TO THE BUSES IN THE LANE. 2) IT CAN OPERATE AT ISOLATED INTERSE-S. TIONS WHERE, DUE TO IRREGUAR TRAFFIC DEMAND, IT IS T£ TALLY INADEQUATE TO APPLY SIMPLE LIGHT SYNCHRONIZATION. THE SYSTEM, THROUGH THE USE OF SENSORS, PICKS UP ON TRAFFIC VARIATIONS AND REGULATES THE TRAFFIC FLOW IN A ACCORDANCE WITH DEMAND. OHPI IFO 'B 3) IT CAN BE USED IN AVENUES OF INTENSE TRAFFIC CROSSING SECONDARY ROADS OF LOW VOLUME. HEN RIGHT OF WAY IS NOT BEING REQUESTED FROM THE SECONDARY ROAD TRAFFIC ALONG THE AVENUE FLOWS WITHOUT INTERRUPT.]-. ON. ON THE OTHER HAND, A REQUEST FOR RIGHT OF WAY FROM THE SECONDARY ROAD WOULD BE TREATED PROMPTLY ALLOWING TRAFFIC TO CROSS, RETURNING THE SIGNAL TO ITS PREVIOUS POSITION. 4) lτ CAN BE USED FOR PEDESTRIAN CRp-§. SING IN FRONT OF SCHOOLS, HOSPITALS AND THEATRES WHERE, TOTAL STOPPAGE OF THE TRAFFIC IS UNJUSTIFIABLE DURING CERTAIN HOURS OF THE DAY. 5) lτ CAN BE INSTALLED IN THE ENTRANCE OF HOSPITALS, FACTORIES, SCHOOLS, MILITARY AREAS, AREAS AND FIVE HOUSES IN ORDER TO SPEED UP THE ENTRANCE OF Z XIT OF VEHICLES. THE SYSTEM CAN BE OPERATED IN FIVE DI£ FERENT MANNERS: CENTRAL, VARIABLE, FIXED, MANUAL OR \_{ TERMITTENT. A - CENTRAL MODE GHE MOST ADEQUATE APPLICATION OF THE SYSTEM IS AT ISOLATED INTERSECTION, WHERE LOCAL TRAFFIC CAN BE OPTIMIZED. THIS, HOWEVER, DOES NOT PREVENT THE POSSIBILITY OF INTEGRATING THE SYSTEM INTO A LARGER .A REA CONTROL NETWORK. I THIS WAY, THE GREEN LIGHT PHASES ARE FIXED IN ACOORDANCE WITH PREVIOUSLY DETERMINED COϋ TROL PLANS. THIS ALLOWS THE EQUIPMENT TO BE SUFFICIENT^ TLY FLEXIBLE TO THE VARIATIONS OCCURRING AT !NTERSE£ TIONS. THIS IS PARTICULARY IMPORTANT IN CITIES IN PR-p. CESS OF RAPID EXPANSION IN THE EXTENT THAT INTERSECTION, NOW ISOLATED,MAY NOT BE IN THE FUTURE. INTERSECTIONS CAN ALSO BE INTEGRATED WITH OTHER INTERSECTIONS HAVING DIF_ FERENT TRAFFIC CONTROL SCHEMES. B - VARIABLE IN THIS FROM THE PHASE SEQUENCE IS NOT FIXED IN CYCLICAL ORDER, BUT RATHER RESPONDS TO THE TRA£ FIC DEMAND. REQUESTS FOR RIGHT OF WAY ARE LINED UP AND THE RESPONSES ARE SEQUENTIAL. FURTHERMORE, THE SYSTEM ADMITS A LINE OF PRIORITY DEMANDS WHICH WOULD BE ATTEJti DED FIRST, PROVIDING THERE IS NO DEMAND IN ANY OF THE TRAFFIC FLOWS AT THE INTERSECTION. THE SYSTEM WILL SWITCH TO FULL RED, GIVING HOWEVER RIGHT OF WAY TO THE FIRST REQUEST. IF AN EVENTUAL BREAKDOWN OCCURS IN A A SENSOR, THE SYSTEM PASSES AUTOMATICALLY TO THE FIXED POSITION. C - FIXED IN THIS OPTION THE SYSTEM CAN CONTROL TRA£ FIC BY USING A FIXED PHASE SEQUENCE IN CYCLICAL ORDER, IN ACCORDANCE WITH A PREESTABLISHED TRAFFIC PLAN, D - MANUAL THIS OPTION ALLOWS THE CHANGE OF PHASE BY MANUAL COMMAND, THE SEQUENCE OF OPERATION IS FIXED IN A CYCLICAL ORDER WITHIN THE TRAFFIC PARAMETERS BY THE OPERATOR. E _ INTERMITTENT IN THE EVENT OF A SYSTEM BREAKDOWN THE SIGNAL LIGHT AUTOMATICALLY TURNS TO INTERMITTENT YELLOW AS A WARNING TO ONCOMING TRAF IC. THE SYSTEM IS ACTIVATED BY SENSORS THAT TRANSFORM THE REQUEST OS RIGHT OS WAY OF A VEHICLE OR PEDESTRIAN INTO AN ELECTRIC SIGNAL, SENDING IT TO THE SENSOR MODULE. F OM THERE, A CORRESPONDI G SIGNAL WILL GO TO THE INTERFACE OF THE MODULES WHICH, IN TURN, GIVES THE ADDRESS AND SWITCH REQUEST. THE MICROPROCESSOR R cεivεs THE LATTER AND SENDS IT TO ROUTINE HANDLING, RE CORDED IN THE PROPRAM MEMORY. IN ACCORDANCE WITH THE RESPONSE OF THAT ROUTINE, A SIGNAL IS SENT TO THE SET OF THE PHASE MODULES, CONTROLING THE SYSTEM. THE FEEDING OF CONTROL PARAMETERS IS MA DE IN THE KEYBOARD SET OR THROUGH DATA TRANSMISSION SYS_ TEM . AN EXTERNALLY SYNCHRON I ZED CLOCK I S PROV I DED FOR * _1_- * _. Wiϊ- CHANGES OF TRAFF IC PLANS AT PREESTABL I SHED HOURS, THE ELECTR IC AL SUPPLY SET CAN RECE I VE ENERGY FROM A RECHARGEABLE BATTERY OR F ROM THE C ITY LJ. NES CONVERT I NG THE ALTERNAT I NG-CURRENT I NTO D I RECT - CUΒ. RENT. THE SPEED OF PROCESSING IS VERY FAST DUE TO THE SHORT TIME CYCLE OF INSTRUCTION WHICH IS MA DE POSSIBLY BY A CRYSTAL FREQUENCY OF 10 MHz. THE TIME OF CYCLE OF THE ICROPROCESSOR IS*. τ„ v 9 900 NS THEREFORE, THE TIME OF EVERY STATE OF THE MACHINE IS 900 NS, AND CONSIDERING THAT THE INSTRU£ TIONS VARY FROM 4 TO 18 STATES, THEY CAN LAST FROM 3.6 TO 16.2 MICROSECONDS. THE DIAGRAMS PRESENTED ILLUSTRADE IN A SCHEMETIC FROM THE FEATURES OF THE SYSTEM.FJGURE I SHOWS THE BLOCK DIAGRAM OF THE COMPLETE SYSTEM, AND F|GURE 2 GIVES AN EXAMPLE OF THE NATURAL SEQUENCE OF FUNCTION. FOR MORE DETAIL ANALYSIS FIGURE 1 SHOWS THE SENSOR MODULE (I) THAT RECEIVES AN ELECTRIC SIGNAL EMITTED BY THE SENSORS (NOT SHOWN IN THE DIAGRAM)} TT ROUGH THE MODULE THE SIGNALS GOES TO THE INTERFACE (2) OF THE MODULES WHICH SUPPLIES THE ADDRESS AND REQUEST FOR RIGHT OF WAY. THE MICROPROCESSOR (3) SENDS A SIGNAL TO ROUTINE HANOLING HOUSED IN TE PROGRAM MEMORY (4). THIS GENERATES A RESPONSE SIGNAL TO THE ROUTINE ANSWER ING WITH A DISPATCH TO THE PHASE SET (5) WHICH, THEN TRAVELS TO THE PHASE MODULE, (6) THE TRAFFIC SIGNAL CQU TROL MECHANISM. THE KEYBOARD INPUT ASSEMBLY (7) OR THE DATA TRANSMISSION SYSTEM (8) RECEIVES THE CONTROL PARA METERS. AN EXTERNALLY SYNCHRONIZED CLOCK HAS ITS INPUT SCHEDULE IN R.E.S. (9), THE MANUAL CONTROL BUTTON INDJ. CATED IN (10) GENERATES A SIGNAL BY MANUAL ACTION. THE SUPPLY SOURCE IS SHOWN IN (II) AND PERMITS GENERATION OF A D I RECT- CURRENT THROUGH AL C I RCU I TS FROM A COMMON ALTERNAT I NG-CURRENT SYSTEM OR RECHARGEABLE BAJ[ TERY. ANY CHANGE IN THE SUPPLY soucε SHOULD BE TOLD TO THE MICROPROCESSOR (3). FINALLY, A SWITCH CONTROL UNIT CONTROLS ALL PRIORITY SWITCHES. FIGURE 2 SHOWS, AS AN EXAMPLE,A DIAGRAM OF THE ATURAL SEQUENCE OF FUNCTION. I THIS DIAGRAMvςg TICAL SHADING INDICATES THE COLOR RED, HORIZONTAL SHA£ I G THE COLOR GREEN THE SQUARE AREAS YELOW.MOVEMENTS |N THE HORIZONTAL AND VERTICAL SHAOES DRIVE TOWARD STA8LE STATES INDICATEO BY INCLINED SHADING IN THE LOWER PART OF THE DIAGRAM. COLUMN F (PHASES) INOIGATES THE PR£ SENT STATE AND THE LINE ECEN (LINE OS RESULTANT FORCE OF BOOL'S GENERAL EXPRESSIONS) SHOWS THE INPUT VARJ. ABLES, AND THE CORRESPONDENT VALUE INDICATES THE FINAL STATE IN THE SQUARE.

Claims: C L A I M S 1) THE INVENTION IS A TRAFFIC LIGHT SYSTEM, COMPUTER CONTROLLED AND ACTIVATED BY REAL TRA£ FIC DEMAND. ADAPTIVE IN NATURE IT FOLLOWS VEHICULAR AND PEDESTRIAN FLOW AND WORKS WITHIN STATISTICAL PARAMETERS FOR USE IN URBAN TRAF IC. THE EQUIPAMENT IS TOTALLY ELE£ TRONIC AND IS CALLED ACTIVATED S|GNAL TRAFFIC CONTROL SγS_ TEM. IT IS CHARACTERIZED BY A MICROCOMPUTER MADE UP OF A CENTRAL PROCESSING UNIT (3) AND BY A DATA BANK (CONNER. TED TO THE MICROCOMPUTER) WHICH RECEIVES THE CONTROL PARA METERS A KEYBOARD INPUT ASSEMBLY (7) ORTHROUGH A SYSTEM OF DATA TRANSMISSION (8). IT CAN ALSO ADDRESS THE MEMORY POSITIONS THROUGH AN INTERFACE OF THE MODULES (2) BY PR£. SENTING A MEANS OF ROUTINE OR PRIORITY TRAFFIC REQUEST THROUGH ITS OWN PROGRAM MEMORY. THIS, THEN, SENDS A S|G_ NAL TO THE PHASE MODULE INTERFACE (6). THE SYSTEM ISSUES A COMMAND SIGNAL THROUGH A CONTROL SWITCH UNIT (12) WHICH CONTROLS PRIORITY SIGNALS. FURTHERMORE, THE ASSEMBLE CAN OPERATE IN FIVE DISTINCT MODES. 2) THE ACTIVATED SIGNAL TRAFFIC Con TROL SYSTEM, IN ACCORDANCE WITH CLAIM I, is ALSO CHARA£ TERIZED BY BEING ABLE TO ADDRESS POSITIONS AND TO FEED PARAMETERS THROUGH A KEYBOARD INPUT ASSEMBLY (7) OR A SYSTEM OF DATA TRANSMISSION (Δ), USING CODIFICATION KEYS IN BINARY NUMBERS. 3) THE SYSTEM, IN ACCORDANCE WITH CLAIM 2, is CHARACTERIZED BY ITS ABILITY TO GENERATE O ΓI ,, W WIIFFOO * ADDRESS THROUGH BINARY COUNTERS BY CYCLECAL COUNT.THESE GENERATE A CORRESPONDING SIGNAL THAT ADDRESSES BY SWITQH I G THE INPUT PULSES OF THE COUNTERS SO THAT THEY RECEJ, VE THE SIGNAL DERIVING FROM THE SENSOR MODULES (1). 5. 4) THE SYSTEM, IN ACCORDANCE WITH CLAIM 1, IS CHARACTERIZED BY THE FACT IT HAS ALSO THE MEANS TO MAKE A DISTINCTION BETWEEN ROUTINE AND PRIORITY S|£ NAL REQUESTS THROUGH A SENSOR MOOULE (L) AND A MOOULE INTERFACE (2) PERMITING SEPARATE GROUPINGS OR LINES OF 0 EACH. FURTHERMORE IT CAN ACHIEVE THIS WITH GREAT SPEED BY THE BREAKING OUT OF A NON-PRIORITY PHASE THROUGH ITS CENTRAL PROCESSING UNIT (3) MODULAR INTERFACE (2), PRQ GRAM MEMORY (4) PHASE ASSEMBLY (5), PHASE MODULE ASSEM BLY (6) AND THROUGH SWITCH CONTROL UNIT (12). 5 5) THE SYSTEM, IN ACCORDANCE WITHCLAIMS I AND 2, HAS THE POSSIBILITY OF CHANGING TRAFFIC PLANS WITHIN THE PARAMETERS OF ITS MEMORY BANK. TRAFFIC PLANS CAN BE SELECTED FOR A WHOLE WEEK, WEEKENDS, OR ON SPECIFIED DAYS, 6) THE SYSTEM, IN ACCORDANCE WITH CLAIM 1, 2 AND 5, FURTHER PERMITS, THROUGH THE CENTRAL PR-FI CESSING UNIT (3), OPERATIONAL SELECTIONS IN FIXED OR VA RIABLE MODES WHEN THE TRAFFIC PLANNING IS ALTERED. 7) THE SYSTEM, FURTHER IN ACCORDANCE i TH CLAIN 1 CAN CHECK ALL VEHICULAR SENSORS THROUGH THE SENSOR MODULE (1) ANO THE CENTRAL PROCESSING UNIT (3). IT CAN ALSO CHANGE AUTOMATICALLY FROM THE FIXED TO THE V RIABLE MODE WHEN THE BREAKDOWN IN A SENSOR IS CORRE£ TED. 8) THE SYSTEM, CAN IN A ACCORDANCE WITH CLAIMS 1 AND 2, THROUGH THE CENTRAL PROCESSING UNIT AND THROUGH THE PHASE ASSEMBLEY,RETURN TO VARIABLE MODE WHEN A SENSOR FAILURE IS CORRECTED. 9) THE SYSTEM,ALSO IN ACCORD WITH CLAIM I, PROVIDES INTERNAL CLOCK ADJUSTEMENT THROUGH THE AID OF -9- A SYNCHRONIZED EXTERNAL CLOCK WHOSE TIMIG IS SUPPLIED BY THE CENTRAL PROCESSING UNIT (3) BY INPUT (9). 10) THE SYSTEM, IN ACCORD WITH CLAIM 1, CAN BE OPERATED MANUALLY GENERATING AN ELECTRICAL SIGNAL TO THE CENTRAL PROCESSING UNIT (3). 11) THE SYSTEM, IN. ACCORDANCE WITH CLAIM I, HAS THE POSSIBILITY TO OPERATE,THROUGH THE CENT ALPRO. CESSING UNIT, IN A CENTRAL MOOE INTEGRATED I TO AN AREA CONTROL SYSTEM. 12) THE SYSTEM, IN ACCORD WITH CLAIMS I AND II, ALSO HAS THE CAPACITY OF HAVING ITS CENTRAL PR£ CESSOR HOOKED UP TO A CENTRAL COMPUTER RECEIVING COMMAND SIGNALS, 13) THE SYSTEM, IN ACCORD WITH CLAIMS I AND 5, IS FURTHER CHARACTERIZED BY THE FACT THAT IS CAN GIVE ASCENDING PRIORITY TO ITS FIVE OPERATIONAL MODεS.

Inventors: ANRAKU L, TONG M
Applicants: ANRAKU L, BRASILEIRA TRANSPORT URBAN, TONG M, BRASILEIRA TRANSPORTES URBANOS EBTU
Application year: 1980
Main classification: G06F15
IPC codes: G06F19, G08G1