|Publication number||US8108071 B2|
|Application number||US 11/970,520|
|Publication date||Jan 31, 2012|
|Priority date||Jul 13, 2007|
|Also published as||US20090015404|
|Publication number||11970520, 970520, US 8108071 B2, US 8108071B2, US-B2-8108071, US8108071 B2, US8108071B2|
|Inventors||Yen-Chun Lin, Jen-Hua Wu, Kuo-Tsung Tseng|
|Original Assignee||Industrial Technology Research Institute|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (9), Classifications (15), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application claims the priority benefit of Taiwan application serial no. 96125624, filed on Jul. 13, 2007. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
1. Field of the Invention
The present invention generally relates to a robot used in a security system, in particular, to a method for coordinating cooperative robots so as to expand a detected range of abnormal events and effectively eliminate abnormal situations in an environment.
2. Description of Related Art
With the advancement of technology and improvement in the quality of our life, the safety of our living environment, such as houses, office buildings, laboratories, factories, financial institutions, and other public places, has become one of main concerned issues. Accordingly, in recent years, various industries have been focusing on developing different security systems, and security service provision has become a fast-developing field. However, an existing commercialized security system has not sufficient mobility and intelligence for detecting different situations, so that a mistaken triggered rate/false alarm rate thereof is very high, which not only causes users to be confused but reduces the reliability of the security system as well. Moreover, security patrol is the most disfavored job for many security staffs, and owing to uncontrollable (physical and mental) factors of human, security routines cannot be fully carried out even imposed with complete regulations. Due to the rapid development of robots in recent years, replacing security staffs with mobile robots (referred as robots thereinafter) to carry out security patrol is made possible.
A single patrol robot is disclosed in Japan Pub. No. 2003051082. The patrol robot includes a control system and a plurality of sensors, such as video, audio, heat, temperature, and gas sensors for monitoring the surrounding environment. When the sensor detects the occurrence of an abnormal event, the sensor sends a message to the robot so that the robot goes to where the abnormal event takes place to collect information. The situation is then evaluated by the control system of the robot according to the collected information and is then processed according to the evaluated result. However, since there is only one robot for monitoring the environment, when the area to be monitored is too large and the communication of the robot is obstructed, the robot may not be able to collect the information of the abnormal event in a short time. Besides, if any malfunction occurs in the robot itself, the entire security system will be invalidated. Moreover, in most cases, the abnormal events, such as a moving intruder, fire, or gas, may spread to many different places; thus, the single robot cannot go to all these places to collect information at one time when more than one sensor detect the abnormal events.
A task takeover mechanism in a cooperative robot system is disclosed in U.S. Pub. No. US20050113974, wherein both a pet robot and a security robot are disposed in a particular environment, and when an event takes place in this particular environment, for example, a house owner comes back, the task is handed over from the security robot to the pet robot so that the pet robot can perform related housework; contrarily, if the house owner leaves the house, the pet robot hands over the task to the security robot so that the security robot can carry out security-related works. In addition to being triggered by occurrences of events, the task handover may also be triggered by the location information of the robots. Taking robots disposed at different floors as an example, when a robot at a particular floor leads a guest to a staircase, the robot detects a location mark of the staircase such that it communicates with a robot at another floor and hands over the reception task to the other robot. However, in the task handover mechanism described above, the task can only be handed over from one particular robot to another particular robot, while the task is still executed by only one robot. In other words, in foregoing two inventions, since elimination of an abnormal event (such as fire) is carried out by only a single robot, the abnormal event cannot be eliminated effectively.
Accordingly, there exists a need for providing a method for coordinating cooperative robots (or referred as multiple robots) to carry out the same task effectively.
Accordingly, the present invention is directed to a method for coordinating cooperative robots. The method includes following steps. First, an abnormal event is detected by a sensor disposed in an environment or in a robot. Then, the abnormal event is broadcasted to a plurality of cooperative robots. Next, each robot determines whether the priority of the abnormal event is higher than that of its currently executing task. If the answer is “yes,” then whether function attributes of the robot meet attributes of the abnormal event is determined. If the function attributes of the robot does not meet the attributes of the abnormal event, the robot broadcasts to acquire help from other robots and constitute an instantly designated task team, and the instantly designated task team goes to where the abnormal event takes place to process and eliminate the abnormal event. Finally, after the abnormal event has been eliminated, the instantly designated task team is dismissed and these cooperative robots resume their original tasks.
The present invention is directed to a method for avoiding task conflict among cooperative robots. The method includes following steps. First, an abnormal event is detected by a sensor. Then, the abnormal event is broadcasted to a plurality of cooperative robots. When a first robot determines that the priority of a task being currently executed is equal to the priority of the abnormal event, the first robot increases weight of the abnormal event and issues a broadcast message of the weighted abnormal event. After that, the first robot continues to execute its task, and a second robot receives the weighted broadcast message. Next, the second robot calcuates the priority to determine which of the abnormal event and its currently executing task has higher priority. If the priority of the abnormal event is higher, the second robot goes to where the abnormal event takes place to process the abnormal event; otherwise, if the task being currently executed by the second robot is higher, the second robot increases the weight of the weighted abnormal event and issues a broadcast message of the twice-weighted abnormal event. Foregoing process will be repeated until a particular robot goes to process the abnormal event.
The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
The robots 5 can move along predetermined routes in the environment or can be self-navigated. As illustrated in
The method for coordinating cooperative robots includes setting up an instantly designated task team and avoiding system conflict. Regarding setting up an instantly designated task team, when a robot which is executing self-navigated patrol, receives a task assigned by the main system or detects an event taking place in the environment, the robot acquires help from other robots which have the same task attributes or are in short distances based on an actual situation in order to, for example, put out a fire or stop a gangster together. When the task is completed, the instantly designated task team is then dismissed and each robot returns to its original status of self-navigated patrol. Regarding avoiding system conflict, the execution of the cooperative robots are distributed in time, space, and functions when they cooperate with one other so that various security tasks can be carried out at different places at the same time. However, a conflict between time, space, or task may happen. For example, a robot is temporarily assigned with a task while it is executing another task. Any conflict may seriously affect the performance of the entire security system. In the present invention, when a system conflict occurs, those related robots can instantly broadcast the conflict so that each of other robots can, according to its operation status, determine whether to accept the request of the robot or relegate the task to another robot.
In the following, an embodiment of constituting an instantly designated task team of cooperative robots will be described in detail.
How to determine the order of the priorities according to the attribute vectors and whether the function attributes of the robot R1 meet the attributes of the event A will be explained herein. Calculations of the priorities of the task P and the event A are disclosed in table 1.
Function attribute vector of robot R1 F1 = (a,b,0,d,0,z)
Dot product of
Attribute vector of
K1 = (0,0,0,0,0,z)
F1 · K1
K2 = (a,b,c,0,e,0)
F1 · K2
As shown in table 1, the function attributes of the robot R1 are described as vector F1=(a,b,0,d,0,z), which means the robot R1 has functions a, b, d, and z, wherein it is assumed that a=26, b=25, d=23, z=1. The attribute vector of the task P is K1=(0,0,0,0,0,z), and the attribute vector of the event A is K2=(a,b,c,0,e,0). When the robot R1 receives a broadcast message, the robot R1 calculates a weighted priority according to the function attribute F1 thereof, the attribute K1 of the task being currently executed, the attribute K2 of the event, the weight W1 of the task being current executed, the weight W2 of the event, and a distance D2 between the robot R1 and where the event takes place (or a distance D1 between the robot R1 and where the task is currently executed), wherein W1=1, W2=4, D1=2, and D2=7. In step S104, the robot R1 determines whether the priority of the event A is higher than that of task P, and through calculation, the priority of the task P is obtained as P1=w1(F1·K1)/D1=½, and the priority of the event A is obtained as P2=w2(F2·K2)/D1=4(262+252)/7≈743.4. Accordingly, the priority of the event A (or task P) is directly proportional to the dot product of the attribute vector thereof and the function attribute vector of the robot R1. Thus, the result is obtained as P2>P1, and accordingly the robot R1 processes the event A first. Taking the event A of “fire setting by an intruder” as an example, the procession of the event A means that the event A is eliminated after by the “fire” is put out and the “intruder” is deterred by the robot R1.
Next, the robot R1 determines whether the function attribute thereof meets the attribute of the event A by subtracting the function attribute vector of robot R1 from the attribute vector of the event A, namely, K2−F1=(a,b,c,0,e,0)−(a,b,0,d,0,z)=(0,0,c,−d,e,−z)=(0,0,24,−23,22,−1), wherein the third and the fifth function are still respectively 24 and 22, which means the function requirement of c and e of event A cannot be met by the robot R1, therefore the function attribute of the robot R1 cannot meet the attribute of the event A. Since the event A cannot be processed because the robot R1 cannot provide functions c and e, then in step S108, the event A is broadcasted to acquire help from other robots having functions c or e. In steps 109 and 109′, after receiving the broadcasted request of the robot R1, the robot R2 (having function attribute c), the robot R3 (having function attribute e), or other robots perform the calculation and determination steps in the dash-line frame 10 to determine whether to accept the request and help to process the event A. When the robots R2 and R3 both determine to accept the broadcasted request of the robot R1, they go to where the robot R1 is and constitute an instantly designated task team with the robot R1, as in step S110. After that, in step S111, whether the event A has been resolved is determined. If the event A has been resolved, step S112 is executed to dismiss the instantly designated task team so that the three robots R1, R2, and R3 respectively resume their original task. If the event A is still not resolved, step 110 is repeated until the event A is resolved.
However, if the robot R1 has all the functions required by the event A, for example, F1=(a,b,c,d,e,z) and then K2−F1=(0,0,0,−d,0,−z), and all the function parameters are smaller than or equal to 0, the robot R1 can process the event A by itself. Accordingly, in step S106, the robot R1 goes to where the event A takes place and then processes it. In step S107, if the event A is resolved, the robot R1 returns to step S101 to resume its original task P; otherwise, the robot R1 repeats step S106 until the event A is resolved.
Certainly, in step S102, the event A, for example, “fire setting by an intruder”, may be transmitted to the main system 3 through the sensor 1 as illustrated in
In overview, the method for coordinating cooperative robots provided by the present invention has at least following advantages:
1. Through information sharing, constitution of an instantly designated task team, and conflict avoidance, a particular task can be completed by a plurality of cooperative robots, and even a malfunction occurs to one of the cooperative robots or task conflict is confronted during the process, other cooperative robots can help to complete the task, so that the task can be completed effectively.
2. Compared with the conventional robot which is disposed with many different sensor systems, the robot in the present invention has simpler system function and accordingly lower cost. Meanwhile, in the present invention, a plurality of robots can be disposed so that a monitored range in the present invention is larger than that in the conventional technique.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US5819008||Jun 14, 1996||Oct 6, 1998||Rikagaku Kenkyusho||Mobile robot sensor system|
|US6266577 *||Jul 13, 1998||Jul 24, 2001||Gte Internetworking Incorporated||System for dynamically reconfigure wireless robot network|
|US6408226||Apr 24, 2001||Jun 18, 2002||Sandia Corporation||Cooperative system and method using mobile robots for testing a cooperative search controller|
|US6438456||Apr 24, 2001||Aug 20, 2002||Sandia Corporation||Portable control device for networked mobile robots|
|US6687571||Apr 24, 2001||Feb 3, 2004||Sandia Corporation||Cooperating mobile robots|
|US7030757||Dec 1, 2003||Apr 18, 2006||Kabushiki Kaisha Toshiba||Security system and moving robot|
|US7165106 *||Apr 17, 2003||Jan 16, 2007||Hitachi Ltd.||Method of managing operation of computer system|
|US20050113974||Sep 30, 2004||May 26, 2005||Kabushiki Kaisha Toshiba||Cooperative robot system and navigation robot system|
|JP2003051082A||Title not available|
|U.S. Classification||700/248, 318/568.11, 700/246, 700/250, 318/567, 318/587, 318/569, 700/245, 700/264|
|Cooperative Classification||B25J9/1682, B25J9/1674, G05B2219/40352|
|European Classification||B25J9/16T1, B25J9/16S|
|Jan 9, 2008||AS||Assignment|
Owner name: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE, TAIWAN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIN, YEN-CHUN;WU, JEN-HUA;TSENG, KUO-TSUNG;REEL/FRAME:020335/0931;SIGNING DATES FROM 20070904 TO 20070905
Owner name: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE, TAIWAN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:LIN, YEN-CHUN;WU, JEN-HUA;TSENG, KUO-TSUNG;SIGNING DATESFROM 20070904 TO 20070905;REEL/FRAME:020335/0931
|Jul 31, 2015||FPAY||Fee payment|
Year of fee payment: 4