CN108870757B - A kind of controlling device for water heater and control method based on plane gesture identification - Google Patents

A kind of controlling device for water heater and control method based on plane gesture identification Download PDF

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Publication number
CN108870757B
CN108870757B CN201810692368.7A CN201810692368A CN108870757B CN 108870757 B CN108870757 B CN 108870757B CN 201810692368 A CN201810692368 A CN 201810692368A CN 108870757 B CN108870757 B CN 108870757B
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Prior art keywords
water heater
control
temperature value
information
gesture
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CN108870757A (en
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杜国铭
窦振龙
冯大志
李美娟
金钊
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Harbin Top Technology Co Ltd
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Harbin Top Technology Co Ltd
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H9/00Details
    • F24H9/20Arrangement or mounting of control or safety devices
    • F24H9/2007Arrangement or mounting of control or safety devices for water heaters
    • F24H9/2014Arrangement or mounting of control or safety devices for water heaters using electrical energy supply
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/017Gesture based interaction, e.g. based on a set of recognized hand gestures

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Human Computer Interaction (AREA)
  • General Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • User Interface Of Digital Computer (AREA)

Abstract

The invention proposes a kind of controlling device for water heater and control method based on plane gesture identification, including input detection unit, main control unit, water heater control unit and display unit.The water heater of plane gesture control is used in the present invention, replace the scheme of traditional pressure buttons and touch key-press using plane gesture control, space shared by the control panel of water heater can be saved, user gesture is detected using camera sensing device, visual angle is broader, operable area is bigger, without any noise, without mechanical wear, do not need firmly to press can be completed control and it is at low cost be easily installed maintenance, it is not stringent to environmental requirement, can also be accurately identified when finger gets wet, mode of operation novelty is laborsaving, provides better user experience.

Description

A kind of controlling device for water heater and control method based on plane gesture identification
Technical field
The invention belongs to technical field of water heaters, control dress more particularly to a kind of water heater based on plane gesture identification It sets and control method.
Background technique
Usually using pressure buttons or touch key-press as control mode, pressure buttons need to occupy one existing water heater Fixed panel space, and increasing with water heater function, number of keys also while therewith increase, and which results in control planes Plate the space occupied is excessive.The use of pressure buttons needs the pressure of certain dynamics.And in key rebound, it can generate certain Noise;When water mist is larger, the accuracy rate of identification will be greatly reduced touch key-press.In the case that especially finger gets wet, press Key can not almost identify the operation of finger.
Pressure buttons: internal elastomeric element is caused to generate elastic deformation and make contact, bullet after release after finger down Property component recoil to initial position enable connect contact be again off.
Touch key-press: the resistance-capacitance network that capacitance type touch key scheme is made up of the capacitor of a resistance and induction electrode The charging and discharging time detect capacitance variations brought by human body touch, and pressing and discharging for key is judged with this.
Pressure buttons need mounting arrangement on the control panel, and the water heater more for function then needs very big control Panel, and due to there are elastomeric element, when operation, need to apply certain pressure.Elastomeric element during rebound usually Along with the noise rattled away;And touch key-press is stringenter to environmental requirement, is unsuitable to apply in the very high environment of humidity, works as hand Finger is not usually available after getting wet, and when there are inductance or magnetic strength in the external world, may cause button malfunction.
Summary of the invention
The present invention proposes a kind of controlling device for water heater based on plane gesture identification to solve existing technical problem And control method.
The purpose of the present invention is achieved through the following technical solutions: a kind of water heater control dress based on plane gesture identification It sets, including input detection unit, main control unit, water heater control unit and display unit;
The input detection unit captures user and is operating for receiving reflection light of the infrared light supplementing device 2 on object The images of gestures that region is formed, and the images of gestures captured is sent to main control unit;
The main control unit first carries out pretreatment and spy to the images of gestures after receiving the images of gestures Sign point extracts, and obtains user gesture information, and the user gesture information and pre-stored Pre-defined gesture information are carried out pair Than when user gesture and Pre-defined gesture determine that successfully then user gesture is processed into corresponding control by combination temperature control strategy System instruction is sent to water heater control unit;The temperature control strategy is to detect current hot water using PT100 temperature sensor Device actual temperature value, it is described to determine that whether successful user gesture changes for determining set temperature value and variable quantity, works as setting When temperature value is higher than actual temperature value, the control instruction is to heat to water heater;
The water heater control unit, for controlling whether water heater is heated according to the control instruction;
The display unit, for the information to user's display water heater.
Further, the input detection unit includes camera sensing device 1 and infrared light supplementing device 2 with optical filter.
Further, the optical filter can only penetrate infrared light identical with 2 wavelength of infrared light supplementing device.
Further, the pretreatment includes that cutting and Threshold segmentation are carried out to images of gestures.
Further, the feature point extraction is to progressively scan to pretreated image data, to each effective Pixel calculates the pixel in its neighborhood relationships, and calculates the picture of continuous multiple frames, so that it is determined that finger in image out Coordinate information, number information, finger moving direction and track sets.
Further, the control device further includes storage unit, for Pre-defined gesture information to be stored in advance.
The present invention also proposes a kind of water heater control method based on plane gesture identification, comprising:
Reflection light of the infrared light supplementing device 2 on object is received, the images of gestures that user is formed in operating area is captured;
Pretreatment and feature point extraction are carried out to the images of gestures, user gesture information is obtained, by the user gesture Information is compared with pre-stored Pre-defined gesture information, when user gesture and Pre-defined gesture determine successfully, then to combine User gesture is processed into corresponding control instruction by temperature control strategy;The temperature control strategy is to be passed using PT100 temperature Sensor detects current water heater actual temperature value, described to determine successful user gesture for determining whether set temperature value changes And variable quantity, when set temperature value is higher than actual temperature value, the control instruction is to heat to water heater;
For display screen to the information of user's display water heater, the information is actual temperature value and set temperature value;
Control whether water heater is heated according to the control instruction.
Further, the pretreatment includes that cutting and Threshold segmentation are carried out to images of gestures.
Further, the feature point extraction is to progressively scan to pretreated image data, to each effective Pixel calculates the pixel in its neighborhood relationships, and calculates the picture of continuous multiple frames, so that it is determined that finger in image out Coordinate information, number information, finger moving direction and track sets.
The water heater that plane gesture control is used in the present invention, traditional pressure buttons are replaced using plane gesture control With the scheme of touch key-press, space shared by the control panel of water heater can be saved, detects user using camera sensing device Gesture, visual angle is broader, and operable area is bigger, and without any noise, no mechanical wear does not need firmly to press control can be completed Make and it is at low cost be easily installed maintenance, it is not stringent to environmental requirement, can also be accurately identified when finger gets wet, mode of operation It is novel laborsaving, better user experience is provided.
Detailed description of the invention
Fig. 1 is a kind of controlling device for water heater structural block diagram based on plane gesture identification;
Fig. 2 is picture catching schematic diagram;
Fig. 3 is 2 method flow diagram of specific embodiment.
Specific embodiment
Technical solution in the embodiment of the present invention that following will be combined with the drawings in the embodiments of the present invention carries out clear, complete Ground description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.Based on this Embodiment in invention, every other reality obtained by those of ordinary skill in the art without making creative efforts Example is applied, shall fall within the protection scope of the present invention.
Embodiment 1
In conjunction with Fig. 1-Fig. 2, the present invention proposes a kind of controlling device for water heater based on plane gesture identification, including input inspection Survey unit, main control unit, water heater control unit and display unit;
The input detection unit captures user and is operating for receiving reflection light of the infrared light supplementing device 2 on object The images of gestures that region is formed, and the images of gestures captured is sent to main control unit;The input detection unit packet Include camera sensing device 1 and infrared light supplementing device 2 with optical filter.The optical filter can only penetrate and 2 wavelength of infrared light supplementing device Identical infrared light.The operating area 3 of water heater is projected on wall plane by operating area projection device 4, the device for projecting Go out a visible static pattern, the sample that the content of pattern is printed by the film being mounted on the laser equipment using laser projection Formula and determine;Interference can be eliminated by increasing infrared light supplementing device, improve the brightness of finger and reduce with this calculation amount of main control chip.
The main control unit, main control unit uses embedded chip, after receiving the images of gestures, first to described Images of gestures carry out pretreatment and feature point extraction, obtain user gesture information, by the user gesture information be stored in advance Pre-defined gesture information compare, when user gesture and Pre-defined gesture determine successfully, then combination temperature control strategy general User gesture is processed into corresponding control instruction and is sent to water heater control unit;Otherwise it is assumed that determining failure, figure is reacquired Picture;The temperature control strategy is that current water heater actual temperature value is detected using PT100 temperature sensor, described to determine successfully User gesture for determining whether set temperature value changes and variable quantity, when set temperature value is higher than actual temperature value, institute Stating control instruction is to heat to water heater, when set temperature value is less than or equal to actual temperature value, the control instruction Not heated to water heater;The pretreatment includes that cutting and Threshold segmentation are carried out to images of gestures.The characteristic point mentions It is taken as progressively scanning pretreated image data, the pixel in its neighborhood relationships is calculated to each valid pixel, And the picture of continuous multiple frames is calculated, so that it is determined that out in image the coordinate information of finger, number information, finger movement Direction and track sets.
The water heater control unit, for controlling whether water heater is heated according to the control instruction;
The display unit, for the information to user's display water heater.
The control device further includes storage unit, for Pre-defined gesture information to be stored in advance.
The present invention also proposes a kind of water heater control method based on plane gesture identification, comprising:
Reflection light of the infrared light supplementing device 2 on object is received, the images of gestures that user is formed in operating area is captured;Heat The operating area 3 of hydrophone is projected on wall plane by operating area projection device 4, which goes out one using laser projection A visible static pattern, the content of pattern are determined by the pattern that the film being mounted on the laser equipment is printed;
Pretreatment and feature point extraction are carried out to the images of gestures, user gesture information is obtained, by the user gesture Information is compared with pre-stored Pre-defined gesture information, when user gesture and Pre-defined gesture determine successfully, then to combine User gesture is processed into corresponding control instruction by temperature control strategy, otherwise determines failure, reacquires image;The temperature Control strategy is that current water heater actual temperature value is detected using PT100 temperature sensor, described to determine successful user gesture For determining whether set temperature value changes and variable quantity, when set temperature value is higher than actual temperature value, the control instruction To heat to water heater, when set temperature value is less than or equal to actual temperature value, the control instruction is not to hot water Device is heated, and image is reacquired;
For display screen to the information of user's display water heater, the information is actual temperature value and set temperature value;
Control whether water heater is heated according to the control instruction.
The pretreatment includes that cutting and Threshold segmentation are carried out to images of gestures.
The feature point extraction is to progressively scan to pretreated image data, calculates it to each valid pixel Pixel in neighborhood relationships, and the picture of continuous multiple frames is calculated, so that it is determined that out the coordinate information of finger in image, The moving direction and track sets of number information, finger.
The water heater using plane gesture control proposed in the present invention, by the click of the finger on metope and sliding come Water heater is controlled, the volume of control panel can be greatly reduced;Any noise will not be generated when control, no mechanical wear uses the longevity Life length, without firmly pressing, and mode of operation is novel, and high sensitivity will not influence to identify finger gets wet.
Embodiment 2
In conjunction with Fig. 3, the water heater of mode temperature adjustment is hit using single indication, is filtered using the narrowband of OV7620 camera and 808nm For mating plate as input detection unit, infrared light supplementing device externally emits an infrared wordline for 808nm wavelength;The platform has used ST public The stm32f407 of department is as main control unit chip;Water heater control unit is added in such a way that relay adds resistance wire Pt100 thermocouple sensor detects water temperature;Display unit shows set temperature value by the way of triode drive digital tube And actual temperature value.
1, system hardware initialization:
The initialization procedure includes: initialization ov7620 camera, and PWM output is used to drive 808nm infrared all the way for configuration Light aid, initialization are used to control the GPIO of relay, and initialization is used to the GPIO of drive digital tube, and initialization is used to detect The analog-digital converter etc. of PT100 temperature simulation amount;
2, obtain image:
Main control chip controls ov7620 camera and obtains image, and is stored in the memory of main control chip;
3, image preprocessing:
The visual angle that can capture due to camera needs exist for being carried out according to actual operating area size than broader Screenshot can greatly reduce the image data of processing, here with 120*160 having a size of screenshot size, using 150 gray values as threshold Value carries out binary conversion treatment to image;
4, feature point extraction:
The image data of 120*160 size Jing Guo binary conversion treatment is progressively scanned, according between pixel Relationship finds out the finger point coordinate position in image.
5, key gesture identification:
Check the finger found out point coordinate whether be located at define by key range, if finger point falls in key 1 In scope, then finger down key 1 is determined, set temperature value increases by 1, otherwise checks whether finger point is located at key 2 Scope in, if it is determine finger down key 2, set temperature value subtracts 1, otherwise it is assumed that finger is not pressed Key, setting value do not change;
6, obtain actual temperature value:
Detect the actual temperature information passed back by PT100;
7, show information:
Show set temperature value and actual temperature value respectively using charactron;
8, water heater computer heating control:
When set temperature value is higher than actual temperature value, needs to heat water temperature, be generated by main control chip corresponding Control instruction notifies water heater control unit to connect relay, connects resistance wire and heats to water temperature.
Above to a kind of controlling device for water heater and control method based on plane gesture identification provided by the present invention, into It has gone and has been discussed in detail, used herein a specific example illustrates the principle and implementation of the invention, the above implementation The explanation of example is merely used to help understand method and its core concept of the invention;Meanwhile for the general technology people of this field Member, according to the thought of the present invention, there will be changes in the specific implementation manner and application range, in conclusion this explanation Book content should not be construed as limiting the invention.

Claims (9)

1. a kind of controlling device for water heater based on plane gesture identification, which is characterized in that including input detection unit, master control list Member, water heater control unit and display unit;
The input detection unit captures user in operating space for receiving reflection light of the infrared light supplementing device (2) on object The images of gestures that domain is formed, and the images of gestures captured is sent to main control unit;
The main control unit first carries out pretreatment and characteristic point to the images of gestures after receiving the images of gestures It extracts, obtains user gesture information, the user gesture information and pre-stored Pre-defined gesture information are compared, when User gesture and Pre-defined gesture determine that successfully then user gesture is processed into corresponding control instruction by combination temperature control strategy It is sent to water heater control unit;The temperature control strategy is that current water heater reality is detected using PT100 temperature sensor Temperature value, it is described to determine that whether successful user gesture changes for determining set temperature value and variable quantity, works as set temperature value When higher than actual temperature value, the control instruction is to heat to water heater;The operating area is set by operating area projection Standby to be projected on wall plane, which goes out a visible static pattern using laser projection, and the content of pattern is by pacifying Pattern that film in laser projection device is printed and determine;
The water heater control unit, for controlling whether water heater is heated according to the control instruction;
The display unit, for the information to user's display water heater.
2. the apparatus according to claim 1, it is characterised in that: the input detection unit includes the camera shooting with optical filter Head sensor (1) and infrared light supplementing device (2).
3. the apparatus of claim 2, it is characterised in that: the optical filter can only penetrate and infrared light supplementing device (2) wave Long identical infrared light.
4. the apparatus according to claim 1, it is characterised in that: the pretreatment includes carrying out cutting and threshold to images of gestures Value segmentation.
5. the apparatus according to claim 1, it is characterised in that: the feature point extraction is to pretreated image data It is progressively scanned, the pixel in its neighborhood relationships is calculated to each valid pixel, and count to the picture of continuous multiple frames Calculate, so that it is determined that out in image the coordinate information of finger, number information, finger moving direction and track sets.
6. device according to any one of claims 1-5, it is characterised in that: the control device further includes that storage is single Member, for Pre-defined gesture information to be stored in advance.
7. a kind of water heater control method based on plane gesture identification characterized by comprising
The reflection light of infrared light supplementing device (2) on object is received, the images of gestures that user is formed in operating area is captured;
Pretreatment and feature point extraction are carried out to the images of gestures, user gesture information is obtained, by the user gesture information It is compared with pre-stored Pre-defined gesture information, when user gesture and Pre-defined gesture determine successfully, then combination temperature User gesture is processed into corresponding control instruction by control strategy;The temperature control strategy is using PT100 temperature sensor Current water heater actual temperature value is detected, it is described to determine successful user gesture for determining whether set temperature value changes and become Change amount, when set temperature value is higher than actual temperature value, the control instruction is to heat to water heater;The operating area By operating area projection on wall plane, which goes out a visible static map using laser projection Case, the content of pattern are determined by the pattern that the film being mounted in laser projection device is printed;
For display screen to the information of user's display water heater, the information is actual temperature value and set temperature value;
Control whether water heater is heated according to the control instruction.
8. according to the method described in claim 7, it is characterized by: the pretreatment includes carrying out cutting and threshold to images of gestures Value segmentation.
9. according to the method described in claim 7, it is characterized by: the feature point extraction is to pretreated image data It is progressively scanned, the pixel in its neighborhood relationships is calculated to each valid pixel, and count to the picture of continuous multiple frames Calculate, so that it is determined that out in image the coordinate information of finger, number information, finger moving direction and track sets.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109724263A (en) * 2019-02-18 2019-05-07 海信(广东)厨卫系统有限公司 A kind of control device, water heater and its control method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109583404B (en) * 2018-12-06 2019-08-02 哈尔滨拓博科技有限公司 A kind of plane gestural control system and control method based on characteristic pattern identification
CN109839827B (en) * 2018-12-26 2021-11-30 哈尔滨拓博科技有限公司 Gesture recognition intelligent household control system based on full-space position information

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102053702A (en) * 2010-10-26 2011-05-11 南京航空航天大学 Dynamic gesture control system and method
CN104110882A (en) * 2014-02-20 2014-10-22 芜湖美的厨卫电器制造有限公司 Water heater and control method thereof
CN104991637A (en) * 2015-05-19 2015-10-21 浙江大学 Close-range non-contact elevator button panel and control method thereof
WO2017031737A1 (en) * 2015-08-26 2017-03-02 罗旭宜 Method for adjusting water heater set-up based on hand gesture, and water heater
CN105045399B (en) * 2015-09-07 2018-08-14 哈尔滨市一舍科技有限公司 A kind of electronic equipment with 3D camera assemblies
CN206833467U (en) * 2017-04-25 2018-01-02 华南理工大学 A kind of visual projection's interactive system based on pattern-recognition
CN107202426A (en) * 2017-05-18 2017-09-26 珠海格力电器股份有限公司 control device and method, water heater
CN107131657A (en) * 2017-06-21 2017-09-05 华帝股份有限公司 It is a kind of can gesture control water heater and its application method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109724263A (en) * 2019-02-18 2019-05-07 海信(广东)厨卫系统有限公司 A kind of control device, water heater and its control method

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