CN101088720B - Obstacle avoidance and anti-falling system and method thereof - Google Patents

Abstract

A system for avoiding obstacle and preventing falling off is prepared as setting at least one displacement transducer on movable body, driving said transducer to scan and detect in fan-shaped range of a certain angle or full circle by a rotary unit, setting a specific angle between signal emitting and receiving path of said transducer and plane set by said body, initializing said transducer to generate a working signal, sending and receiving signal by said transducer, sending received signal to a control unit, receiving received signal by said control unit and carrying out comparison operation with working signal to judge whether there is obstacle or height drop in advancing direction and driving said body to turn around for avoiding obstacle and preventing falling off.

Description

Obstacle avoidance and fall prevention system and method thereof

technical field

The present invention relates to an obstacle avoidance and fall prevention system and its method, in particular to an obstacle avoidance and fall prevention system for a mobile device, which uses a displacement sensor installed on the mobile device to transmit and receive reflections The signal can be judged as an obstacle or a height difference, and at least one set of sensors can be used to achieve the functions of obstacle avoidance and fall prevention at the same time, which can greatly simplify the design and device cost of the mobile device. the

Background technique

When the self-propelled mobile device (or commonly known as a robot) is running in a specific work area, it moves according to the preset travel mode. If the mobile device accidentally collides with an obstacle or falls to a height drop during the travel process If it gets stuck, or even falls from a high place, it is easy to cause damage to the mobile device and cannot continue to operate. Therefore, for a self-propelled mobile device, obstacle avoidance and preventing the device from falling are essential. Function. the

For traditional self-propelled mobile devices, the sensing functions for avoiding obstacles and preventing the device from falling are usually performed by two independent sensing components, such as infrared, ultrasonic or mechanical buffers. Assemblies, the disadvantage is that the design of the mobile device itself is relatively complicated and requires high cost. the

Please refer to Fig. 1, which is the U.S. Patent Early Publication No. 20040143930 "Obstacle sensing system for an autonomous cleaning apparatus", which provides an obstacle detection system for a self-propelled cleaning device. The mechanical bumper (Bumper) 11 is the main component of obstacle detection. When the bumper 11 collides with an obstacle, it will generate a signal to inform the system; The obstacle avoidance function can only be achieved after direct contact with the collision, and the system is easily damaged by multiple collisions for a long time. the

Please refer to Fig. 2 again, U.S. Patent No. 6,594,844 "Robot obstacle detection system", which provides a robot obstacle detection system 20, the system 20 utilizes multiple sets of sensors with functions of infrared emission and optical signal reception The detectors 21 and 22 are used as the main detection components, wherein the detector 21 is arranged in front of the robot 23 to detect obstacles or walls ahead, and the detector 22 is arranged at the bottom of the robot 23, It provides anti-drop detection, through which the purpose of obstacle avoidance and anti-drop is achieved; however, since the detection directions of the detectors 21 and 22 are fixed, multiple groups of detectors must be provided to expand the detection angle and Orientation, otherwise there is a detection dead angle. As shown in the figure, three sets of detectors 21 and 22 are respectively provided, which makes the structure more complicated and the cost required is relatively high. the

Contents of the invention

In view of the defects of the prior art, the main purpose of the present invention is to propose an obstacle avoidance and fall prevention system and its method, which uses the displacement sensor installed on the mobile device to transmit and receive reflected signals to judge as an obstacle Objects or height differences can be achieved by using at least one set of sensors to simultaneously achieve the functions of obstacle avoidance and fall prevention, which can greatly simplify the design and device cost of mobile devices. the

In order to achieve the above object, the technical solution adopted by the present invention is to propose an obstacle avoidance and fall prevention system, which includes:

a body;

At least one driving wheel is arranged on the body for supporting and moving the body;

At least one displacement sensor is arranged on the body for transmitting and receiving signals. The path of transmitting and receiving signals forms a specific angle with the plane on which the body is set. The specific angle formed by the set plane is greater than 0 degrees and less than 90 degrees;

A rotating device is used to drive the displacement sensor to rotate reciprocally within a certain angle range or to rotate in a full circle; a control unit can receive and process the signal of the displacement sensor to determine whether there is an obstacle or a height difference in the direction of travel, And output a signal to drive the body to turn. the

Preferably, the displacement sensor can be one of an optical sensor, an acoustic wave sensor or a combination thereof. the

To achieve the above purpose, the present invention also proposes an obstacle avoidance and fall prevention method, which is to install at least one displacement sensor on a movable body to detect the traveling route of the body, which includes:

-Set the transmission and reception path of the displacement sensor and the plane on which the body is set to form a specific angle and initialize, the specific angle between the transmission and reception signal path of the displacement sensor and the plane on which the body is set is greater than 0 degrees and less than 90 degrees, and the displacement sensor is driven by a rotating device, and scans and detects within a sector range of a certain angle or a full circle rotation;

- the displacement sensor sends and receives signals and transmits the received signals to a control unit;

- The control unit receives the received signal and calculates and judges the command output. the

The above and other technical features and advantages of the present invention will be described in more detail below in conjunction with the accompanying drawings. the

Description of drawings

Fig. 1 is a structural schematic diagram of an existing obstacle detection system of a self-propelled cleaning device;

Fig. 2 is a structural schematic diagram of an existing robot obstacle detection system;

Fig. 3 A is the structural representation of preferred embodiment of the present invention;

Fig. 3 B is the right side view of the embodiment shown in Fig. 3 A;

Fig. 3 C is the top view of the embodiment shown in Fig. 3 B;

Fig. 4 is a schematic view showing that the present invention is implemented in an obstacle state;

Fig. 5 is the state schematic diagram showing that the present invention is implemented in height drop;

Fig. 6 is a flowchart of the method steps of the present invention. the

Explanation of reference signs: 30-obstacle avoidance and fall prevention system; 31-body; 32-driving wheel; 33-displacement sensor; 331-signal transmitting device; 332-signal receiving device; 34-control unit; 35-rotating device ; 40-plane; 41-sag; A-advance direction; Sp-signal path; SR, SR1, SR2-reflection signal; Sw-working signal; θ, θ1-angle. the

Detailed ways

The technical means and effects used by the present invention to achieve the purpose will be described below with reference to the attached drawings. Please refer to the preferred embodiment shown in Figure 3A to Figure 3C, the obstacle avoidance and fall prevention system 30 provided by the present invention has a body 31, and at least one driving wheel 32 is provided at the bottom of the body 31, which can be used for support and To move the body 31, a displacement sensor 33 is provided on the body 31. The displacement sensor 33 can be one of an optical sensor, an acoustic wave sensor or a combination thereof. It includes a signal transmitting device 331 and a signal receiving device 332. The signal The transmitting device 331 is used to transmit signals, and the signal receiving device 332 is used to receive the reflected signal SR. The signal paths Sp of the signal transmitting device 331 and the signal receiving device 332 form a specific angle θ with the plane 40 on which the main body 31 is set. , and the specific angle θ is greater than 0 degrees and less than 90 degrees, the action of sending or receiving signals at the signal transmitting device 331 and the signal receiving device 332 can be controlled by a control unit 34, and the control unit 34 can receive and The received signal received by the signal receiving device 332 is processed. the

As shown in Fig. 3B and Fig. 3C again, this displacement sensor 33 is arranged on a rotating device 35, can drive this displacement sensor 33 to rotate within the scope of certain angle θ1 by this rotating device 35 to carry out scanning detection, certainly, this The rotating device 35 can also rotate in a full circle to synchronously drive the displacement sensor 33 to rotate in a full circle or reciprocate. In this way, the detection range of the displacement sensor 33 can be expanded, not limited to the forward direction A of the body 31; The rotating device 35 can be rotated by components such as gears, belts or chains, and its structure is a prior art that is easily achieved by those skilled in the art, and will not be repeated here. the

Please refer to Fig. 3A, the default state shown in Fig. 3A is the initial state, which has a working signal Sw, the working signal Sw is preset as the reflection signal SR=Sw of the normal state, and the working signal Sw is stored in the control In the unit 34; as shown in Figure 4, there is an obstacle 50 on the plane 40. When the main body 31 moves to the obstacle 50, the reflection signal SR1 is weakened due to the obstruction of the obstacle 50, and the displacement sensor 33 Receive the reflection signal SR1 and send it to the control unit 34, the control unit 34 can compare the reflection signal SR1 with the initial working signal Sw, because the reflection signal SR1 is smaller than the working signal Sw, the control unit 34 can judge It is known that there is an obstacle 50 ahead, so the obstacle avoidance algorithm is performed, and an instruction can be output to drive the main body 31 to turn or stop; as shown in Figure 5, there is a height lower than the plane 40 in front of the forward direction A of the main body 31 When the main body 31 moves to the front of the depression 41, the reflection signal SR2 will increase. The displacement sensor 33 receives the reflection signal SR2 and transmits it to the control unit 34. The control unit 34 can reflect the reflection signal SR2. The signal SR2 is compared with the initial working signal Sw. Since the reflected signal SR2 is greater than the working signal Sw, the control unit 34 can judge that there is a depression 41 ahead, so it can perform anti-drop calculation algorithm and output instructions to drive the The main body 31 turns or stops. the

Please refer to FIG. 3A and FIG. 6 at the same time. In summary, the obstacle avoidance and fall prevention method 40 provided by the present invention can be summarized, which includes the following steps:

Step 41: Initialize the displacement sensor, set the transmission and reception path of the displacement sensor 33 to form a specific angle with the plane 40 set by the main body 31 and initialize it;

Step 42: The displacement sensor sends and receives signals. After the initialization step in step 41 is completed, an initial working signal Sw is obtained, and then the displacement sensor 33 is controlled to start sending and receiving signals, and the receiving signal SR is sent to the control unit 34;

Step 43: The control unit 34 performs calculation and judgment and outputs the command, which includes an obstacle avoidance judgment 431 and a fall prevention judgment 432. If the received signal SR is less than the working signal Sw (4311), the obstacle avoidance algorithm is performed 4312, return to step 42 after the situation is eliminated, if it is not satisfied that the received signal SR is smaller than the working signal Sw (4311), then perform the anti-drop judgment 432, if it meets the condition that the received signal SR is greater than the working signal Sw (4321), then proceed Anti-drop algorithm 4322, return to step 42 after the situation is eliminated, if it does not meet the received signal SR greater than the working signal Sw (4321), then return to step 42, continue to send and receive signals by the displacement sensor 33, and will receive The signal SR is transmitted to the control unit 34; when the aforementioned conditions are excluded, it means that the control unit 34 outputs the calculation judgment command to drive the body 31 to turn or stop, which can be included in the algorithm process, so it is not shown in Figure 6 Furthermore, in this embodiment, the obstacle avoidance judgment 431 is executed first, and then the fall prevention judgment 432 is executed, but the order of the two can be reversed, and is not limited to the order of the icons. the

It must be emphasized that the present invention uses voltage signal changes to judge obstacles or height drops, which is different from traditional infrared switch detection (that is, the embodiment shown in Figure 2), as long as a group of sensors can be used to simultaneously achieve avoidance. Obstacle and anti-drop detection, not only the system structure is simple and the cost is low. the

The above descriptions are only preferred embodiments of the present invention, and are only illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all will fall within the protection scope of the present invention. the

Claims (2)

1. keep away barrier and the anti-system that drops for one kind, it is characterized in that it comprises:

One body;

At least one driving wheel is arranged on this body, is used in to support and move this body;

The displacement transducer of at least one sonic sensor form, it is arranged on this body, and in order to emission and reception signal, the path of its emission and reception signal is to become a special angle with the set plane of this body, and said special angle is greater than 0 degree and less than 90 degree;

One tumbler is arranged on this body, in order to drive this displacement transducer in the fan-shaped range of certain angle or the scanning detecting of wholecircle revolution;

One control module is arranged on this body, receives and handle the signal of this displacement transducer, to judge direct of travel whether barrier or height fall is arranged, and exports a signal and turn to drive this body;

Wherein, the reflection signal of sensor normal condition as preset working signal Sw, and will be worked as front-reflection signal SR by control module and compared with work signal Sw, SR＜Sw then is judged as the place ahead has barrier, carries out and keeps away the barrier algorithm; SR＞Sw then is judged as the place ahead has recess, carries out the anti-algorithm that drops.

2. keep away barrier and the anti-method that drops for one kind, its be one movably at least one sonic sensor form is set on the body displacement transducer in order to detect the course of this body, it is characterized in that, comprise following steps:

Set the emission of this displacement transducer and the path of reception signal and become a special angle and initialization with the set plane of this body, wherein said special angle is greater than 0 degree and less than 90 degree;

This displacement transducer is driven by a tumbler, in the fan-shaped range of certain angle or the scanning detecting of wholecircle revolution;

This displacement transducer sends and receives signal, and the signal that is received is sent to a control module;

Receive and the decision instruction of reception signal union to export by this control module;

Wherein, the reflection signal of sensor normal condition as preset working signal Sw, and will be worked as front-reflection signal SR by control module and compared with work signal Sw, SR＜Sw then is judged as the place ahead has barrier, carries out and keeps away the barrier algorithm; SR＞Sw then is judged as the place ahead has recess, carries out the anti-algorithm that drops.

Images