Automated Bluetooth Plant Watering using Humidity Sensor

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1 164 Automated Bluetooth Plant Watering using Humidity Sensor Asst. Prof Dept. of ISE, RVCE, Bangalore, India ABSTRACT Bluetooth Low Energy is also known as Bluetooth Smart is a wireless technology designed for low energy consumption compared to Bluetooth classic. This paper presents the design and implementation method of low cost but yet efficient and provides good performance for plant watering system in a garden using the Bluetooth low energy humidity profile. The communication between the humidity BLE sensor and smart phones will be wireless. Keywords- BLE (Bluetooth low energy); BT (Bluetooth) INTRODUCTION This paper includes the technology which is an integration of mobile devices with humidity sensors, these humidity sensors helps Agriculturist/Farmer (watering the plants) and also for Human health concerns. This paper solves the problem of watering plants (especially when growing the sensitive plants).each users has multiple devices such as smartphones etc. while plants needs variable watering during different seasons. Humidity sensor is a device which can measure the humidity level in the soil as well as in the open environment. The key objective of the innovation is to assist Agriculturist/Farmer to provide the information present on the humidity sensor via mobile devices such as mobile phones, By viewing the information on the mobile device, further it is possible to start the water pump set via mobile phones, When the desired humidity level is normalized the pump set can be switched off automatically. Consider a scenario in which we are considering sensitive fruit plants such as pomegranate, banana and vanilla. These plants are very sensitive in nature, Such that watering more will lead these plants to get decay, on the other hand providing less water will make these plants get dried up. In these cases it is very important to maintain the normal humidity (moisture) level of soil. Also we have another use case with respect to health care concern, the key objective is to assist a human though the information present on the humidity sensor to mobile phone when the surrounding humidity crosses the threshold and drops down below the normal limit. By getting alerted by information we can avoid the following problems. 1) During the summer season there will be more humidity level, in case plants need more water and in winter and rainy season it will be vice-versa. 2) Humidity sensors with a BLE chip can sustain and provides a longer serving period, which helps easy to watering plants while maintaining a correct ratio of water level. This proposal is intended to assist the human being to have a perfect information to avoid the future problems via wireless interface by mobile phones. System Overview Fig 1 illustrates the overall network establishing and controlling function of the system. The system can be installed in middle of the plants which can cover a part of the garden. Bluetooth wireless connection enabled the system can communicates with an application on a smart phone. Since there is a BLE humidity sensor used in the entire process, GATT layer provides an interface for communication of the BLE profile which can communicate via Bluetooth stack. The Humidity sensors used for getting the information will be enable d with the wireless Bluetooth technology and the mobile devices like smartphones/tablets will be used to collect the information from the particular sensor device. As these devices comes into the range of Bluetooth. Each sensor device will be given a name or number, such that the user can able to recognize and differentiate between the sensor devices and can take action according to the resultant values we get form the sensor device. In this proposed solution user don t have to go and check each and every sensor readings, as soon as the user enters into the range of humidity sensor devices, the user will be enabled to get the information from the sensors.

2 Fig 1 overall network establishing and controlling function of the system. If it is a big field, it is possible to send the values collected by Bluetooth humidity sensors to mobile devices which is far from the device by the means of repeaters or we can pass those values to the next near devices which can again send those values again till it reaches the mobile devices. In order to improve the performance and battery life, Bluetooth low energy based sensors are used, these devices has an ability to run couple of years on a coin cell battery. Which will be of 3V 250mAh. Initially, sensor will be buried inside the soil, or may be tied to the near of the plant root, such that can provide the exact soil humidity information. These humidity sensors will be embedded with the low energy chip, which can advertise the information which is sensed by the humidity sensors. Any user with a smartphone with a Bluetooth low energy support can use an application to read the advertised information from the device. The application further helps the user to take the action based on the plantation or the crop which is on the filed or a garden. Whenever the data collected on the smartphone reached the threshold limit, the application provides the suggestion for taking the action. Further user can switch on the water pump manually or ever it can be automated. This paper talks about the connection and establishment of network between the humidity sensor and the smart phones. In the same way when the desired humidity level is reached again the water pump can be made switch off automatically. Further these information can be made to store on cloud or maintaining a database for better improvements, by seeing the pervious overviews. Fig 2 illustrated the communication between the smartphone and the Bluetooth low energy humidity profile. 165

3 Methodology Humidity sensors will be placed inside the soil on the farming field. The sensor in turn can sense the humidity level present in the soil. The humidity sensor will be embedded with the Bluetooth low energy chip as shown in the above design. The interface for connecting the sensor and the BTLE chip can be any interface and it could be one embedded solution. The humidity sensor would inform BTLE chip any changes in the expected values in the soil through the wired interface. This information would be then transferred to the remote devices over BTLE protocol and profile. There would be different part of BLE profile which would run on mobile or any computer system and on the humidity sensor device. Here Humidity monitor will be acts as a central device and Humidity reporter as a peripheral device. In the same way Humidity monitor will be a GATT Client and the Humidity reporter will be a GATT Server in case of profile implementation perspective for Bluetooth low energy profile. Fig 3.below illustrates the profile roles of the Bluetooth Low Energy. Software Design Software design section includes the main functions of the system designed in the sensor and the smartphone respected operating system supported application. The data format of Bluetooth Low Energy packet will be as shown in the Fig

4 A. communication between sensor and smart phone Fig. 4 illustrates the process of communication initiation and termination in the proposed system. The advertising starts from the BLE module, as soon as the sensor starts reading the humidity data the BLE module integrated to the sensor starts advertising the data. Fig. 6 Advertisement of Bluetooth Low Energy data from the sensor device. B. Android GUI The application is designed in Android version with 5.1 and KitKat support with API level 18. The application is will be designed with the API level 18 so that the application will support and run on the device which are enabled with the Bluetooth Low Energy. In this stage application is designed to read the humidity and temperature data from the Bluetooth LE devices. Fig 6. Illustrates the Android GUI tested on smart phone with version KitKat. The interface is simple to use and can be turn off and turn on using simple UI functions. The application will runs and collect data with the GATT server running on the smartphone as well as the BLE device. Snapshot of requesting to switch on Bluetooth on smart phone. 167

5 Note: Please note that this document talks about Humidity sensors and the mobile devices such as smartphones, tablets etc. Please note that since the range of Bluetooth is not too strong enough to reach kilometers, we may make some access points for few number s of sensors, where from that access points, it is possible to get the multiple information from different devices. (OR) it is possible to send the values collected by Bluetooth humidity sensors to mobile devices which is far from the device by the means of repeaters (OR) we can pass those values to the next near devices which can again send those values again till it reaches the mobile devices. Fig 8. Illustrates the humidity and other sensor reading from an sensor devices, here the sensor will always sends the raw data which will be in Hex decimal format. We need to use an algorithm to make it show as in human readable format. C. Algorithm to converting the senor reading into human readable format. Humidity sensor data format on BLE. Algorithm /* Conversion algorithm, humidity */ double calchumrel(uint16 rawh) { double v; rawh &= ~0x0003; // clear bits [1..0] (status bits) //-- calculate relative humidity [%RH] -- v = /65536 * (double)rawh; // RH= * SRH/2^16 return v;} 168

6 Experimental Results and Analysis Throughput analysis as per the BPA 600 Sniffer. Fig 9. & Fig 10. Illustrates the throughput analysis for data transfer between smartphone and the BLE sensor device. Fig 10. Coexistence Conclusion In conclusion, this low cost and power efficient system is designed to improve gardening. The wireless control function by smart phone provides help and assistance especially while sensitive plant are in the garden or in the field, implementation of Bluetooth Low Energy system help ease of use with less cost and 169

7 durability. Considerably can be more useful for the agriculture system. Since the Bluetooth Low Energy rage is too short as compared to the Wi-Fi, we may have to make use of repeater or hoping technique to regenerate the advertising data from the sensor device. This solution is not only restricted to Bluetooth Low Energy, also can be implemented on Wi-Fi but, the concept of Low Energy will be vanished. For future work, the Android GUI will be integrated with more sensor readable power to make the use-cases automated. Also further Android GUI will be implemented with the voice recognition control. All future work will be expected to be done without extra expenditures on the proposed technology. Acknowledgement I would like to thank Mr. Nitin Kumar Agarwal, Mr. Girish A Joshi and my other team members for their help in implementing Bluetooth profiles and reviewing this paper. References [1] The official Bluetooth website from Bluetooth SIG: [2] 2014 IEEE International Symposium on Bioelectronics and Bioinformatics (IEEE ISBB 2014) A Heart Rate Detection Method for Low PowerExercise Intensity Monitoring Device Eka Adi Prasetyo Joko Prawiro, Chia -Chun Hu, Yi-Sheng Chan, Cheng-Hung Chang, and Yuan-Hsiang Lin*Department of Electronic and Computer EngineeringNational Taiwan University of Science and TechnologyTaipei, Taiwan [3] 2nd Mediterranean Conference on Embedded Computing,,/" MECD 2013 Advertising semantically described physical itemswith Bluetooth Low Energy beacons Janne Takalo-Mattila, Jussi Kiljander, Juha-Pekka SoininenVTT Technical Research Centre of FinlandOulu, Finland [4] 2015 IEEE International Conference on Consumer Electronics (ICCE) Smart Office Energy Management System Using Bluetooth LowEnergy Based Beacons and a Mobile AppMoonok Choi*, Wan-Ki Park*, Ilwoo Lee**Electronics and elecommunications Research Institute. [5] 2014 Seventh International Symposium on Computational Intelligence and Design Wireless Thermometer Based on Bluetooth 4.0 Low-energyHongjie Li, Jian Luo Electronic Science and Technology Research InstituteUniversity of Electronic Science and Technology of ChinaChengdu, China 170