Multichannel Electronic Choke Indicator System for tractor Driven Seed Drills

Seed drills are extensively used with tractor for sowing seeds in Agricultural fields. Modern seed drills are famous for its proper sed rate, uniform distribution and correct placement of seeds in soil, while sowing nine channels seed drills are generally manufactured in the country and are being used. Seed pass through the seed tubes of the seed drills before dropping into furrows in fields. Due to excess moisture in soil or some other reason the seed tubes often get choked/blocked while sowing. To detect such choking a labourer is to be employed simply for monitoring the seeding operation. But due to human error often he fails to detect the choking immediately, resulting omission of seeding in certain rows in fields. This causes non uniform distribution and also reduces the yield. The above problem is more serious when sowing is done in night times.

Keeping the above in view, ALFA Centre has developed a Multichannel Electronic Choke Indicator which monitors seed dropping through seed drills and gives audio/visual indications to the tractor driver whenever seed tube(s) get(s) choked and /or seed box becomes empty.

Main features of the developed system :

During normal sowing condition, green LED of the Status Indication Panel glows. While sowing, anyone or more seed tubes of the seed drills, if get choked, corresponding red LED(s) of that channel(s) glow(s) together with audio alarm.The status of the seed box is also monitored by the system. During sowing when seed box becomes empty, the system indicates this status by glowing a yellow LED Channels (expandable) along with audio alarm. The system can be made operational using Power Supply: Through tractor the tractor battery or a separate rechargeable battery or 6V 6 volt battery. Since the status indication panel of the rechargeaole system is small in size, it can be fitted near battery the seat of the tractor driver, so that he can take corrective measures according to the audio-visual indication The developed system will help farmers to carry out sowing in a proper way for obtaining better yield. The system has undergone extensive field trials and found working satisfactorily.

Soil Moisture Indication system

Generally farmers are not using any soil moisture device for irrigation scheduling. It is mainly due to non availability of suitable soil moisture measurement system for farmers use. Keeping this in view a low cost easily operateable Soil Moisture Indication System is designed and prototype fabricated. The system consists of panel of light emitting diodes i.e. green yellow and red. Gypsum block is used as soil moisture sensing device. For using the system, number of sensors (depending upon the size of a field) have to be implanted at a particular depth i.e. near the root zone of the crop. By connecting sensor terminals to this instrument., status of soil can be found.

Microprocessor Based Grain Moisture Measurement System

The quality of grains is influenced by its moisture content. Moisture content of food grains/seeds is required to be measured due to various reasons, such as to know the status of moisture in grains/seeds before storage, to know optimum stage of harvesting of a crop, to price the agricultural products in mandi and for, R&D purposes.

The system works on the capacitance measurement principle. The grain sample of fixed quantity is to be poured inside the grain chamber for the measurement of grain moisture. Grain acts as a dielectric medium. Temperature sensor (thermistor) embedded inside grain chamber senses grain temperature and incorporates temperature compensation in the measurement. The system is calibrated for wheat, paddy & soybean. However, a user can calibrate the system at his level for other grains also (detailed calibration procedure to be adopted for the purpose will be supplied). The quantity of the sample required for measurement is around 500 gm (varies with commodity).

Microcontroller Based Rice Polish Measurement

The operation of removing bran layer from brown rice is known as polishing. This operation is very critical and the milling quality and quantity of rice depends on polishing process. The polishing operation in rice milling is important in terms of obtaining optimum polish percentage, avoiding breakage losses and consumption of energy. By quantitatively measuring the polish level one can enhance the quality of rice during polishing operation.

The rice polish measurement system is microcontroller based and gives the readings directly in terms of polish percentage of rice samples for the calibrated varieties. The principle of operation is by measuring the reflected levels of electromagnetic radiation from rice samples. Reflected radiation has two components, diffuse and specular. In the system, diffuse radiation from the rice sample is measured. A narrow band of monochromatic radiation is directed on the rice sample. The sample absorbs some of the radiation, the rest is reflected. More polish on the rice sample, less the amount of absorbance and more radiation is reflected from the sample. The reflected radiation from the rice sample is the measure of level of polish in the sample.

Fertilizer Testing Kit

Increasing demand of chemical fertilizers with escalating cost is leading to the sell of sub- standard fertilizers in some regions of the country. The quality of fertilizers are of utmost important to obtain optimum yield of any crop. At present, there is no simple instrument and technique for accessing the quality offer fertilizers at village/user level. The fertilizer testing kit developed by the ALFA Centre can be used for determining approximate percentage of adulteration in chemical fertilizers (phosphatic fertilizers and urea).


The system consists of few chemicals, limited glassware and a photometer The photometer is having optical head unit, sample holder, signal conditioning circuitry and digital display. Photometric method hasbeen used fordetermining the level of adulteration. In the photometer, monochromatic radiation is obtained from blue light emitting diode. This radiation is allowed to pass through the prepared sample resulting in absorption of the radiation in proportion to concentration of the sample.

Soil Nutrient Estimation system

Soil-testing is a well recognised practice for the determination of factors like plant available N,P,K,S (Nitrogen, PhosphoruS,Potash and Sulphur), certain micro-nutrients, and other parameters. Soil-test values are used for Ule formulation of fertiliser recommendations. The available nutrient contents in the soil is categorized in different bands and these bands are designated as VL, L, M, H and VH (i.e. Very Low, Low, Medium, High and Very High nutrient levels). Each band is a concentration band between two values of the nutrient contents. Band level measurements are being used in soil testing for recommending fertilizer doses to the farmers.


The system facilitates the determination of organic carbon (indirect nitrogen), available phosphorous and sulphate in soil. Photometric methods are adopted for quantitative analysis. The system has some novel features as:

Differential mode of analysis
Opto-electronic working
Results obtained are directly usable for fertiliser recommendation

Optional attachment, microcontroller based read-out for knowing the available nutrients levels in ppm and kg/ha. Nutrient band level calibrations are also provided for available phosphorous

Two light emitting diodes (Red & Blue) have been used as an excitation sources for obtaining mono-chromatic radiation and photo-transistors are used as detectors. A user can opt quantitative analysis of I Organic Carbon, Phosphorus or Sulphur by pressing N, P and S keys followed by pressing RUN key. After calibration, the readings can be obtained in kg/ha or ppm values as per option selected


FERTEC is a fertiliser recommendation package. This is a decision aid package for recommendation of fertilisers based on soil-test values of major nutrients-Nitrogen, Phosphorus, Potassium ( N, P, K)-present in a cultivator's field. The package has been developed at the UNDP-DoE-Microprocessor Application Engineering Programme. It is designed using the empirical relationship, formulated by the All India Coordinated Research Project on Soil-Test Crop Response Correlation of Indian Council of Agricultural Research, based on the field experiments conducted by the project's centre with Dept. of Soil Science & AgricuItural Chemistry for various crops cultivated in different agroclimatic regions of Odisha.

Grain Moisture Meter

Grajn moisture meter is a portable instrument which is handy, light weight, and easy in operation. The moisture meter is designed to provide ease of operation combined with a calibration chart corresponding to the reading of the moisture meter (presently calibration of wheat comn1odity is completed). The moisture can be read out on 3. digit LCD display. Grain/seed sample of 450-500 gm is filled in the grain cell upto a particular level. Measurement of grain moisture for each sample takes about 30 seconds. It is a non-destructive measurement without affecting the sample. There is no need to weigh the grain sample.