Plough Depth Sensor


Team: Ritu Goyal, IIT Delhi | Paras Chopra, IIT Delhi | Girish Joshi, RGIPT Jais


Problem Statement


Optimum depth of tillage operations is required for better yield of crops. Soil profile including moisture content, compactness and texture affects the depth of operation. Farmers using the bullock drawn plough try to maintain the depth of operation based on their experience, however it is very difficult to know the variation until it is too much. Therefore, there is need of developing a low cost sensor and alarm system, which may give alarm, if there is variation in depth of operation. The farmer can accordingly adjust the depth of ploughing by adding/removing weight on the plough or changing the angle of beam.

There is need of developing a low cost sensor which can be used to sense depth of operation irrespective of tillage implements (plough, harrow, cultivator, seed drill, etc.) and alarm in case the variation is beyond the pre-set limits.


Sensor Guidelines

  1. The sensors and alarming system should be low cost, robust enough to work in agricultural fields.

  2. The attachment should easily be fitted with the existing tractors and its attachments (tillage implements)

  3. The unit should consume minimum power; preferably it should have its own power source

  4. The unit should have provision of setting the optimum depth of operation and allowable variation, which user may adjust according to type of crop

  5. The unit should be compact in design and light weight. 


Prior Art Searches


Regions of high mechanical resistance in the soil may arise naturally, by compaction from heavy farm machinery, or by the formation of plough pans. Compacted soils with high strength reduce growth rates of crop roots and thus limit the acquisition of water and nutrients by the plant. This may affect crop yield and require tillage practices to reduce soil compaction. Although conventional methods of crop management provide similar soil conditioning across the entire field, different parent material, topography, and past management can cause a significant variability in soil compaction. Depth of ploughing affects both perennial weed infestation and yield levels consistently. Depth of ploughing and sowing depends on the crop. Every crop has optimum depth of sowing. If the seeds are sown deeper then the tillering is delayed. Therefore, sensing the depth of tillage operations is important as it provides a feedback to the framer to correct for any irregular tillage that might have occurred.

Methods developed for online depth sensing till now use ultrasonic sensors to find the depth of ploughing. One of the challenges associated with the ultrasonic sensors is that they cannot accurately measure the distance in presence of dust particles and grass on farm. In another method, a swinging arm type of frame height sensor was designed to measure the distance variation between the soil surface and the frame of sensor system. 


Mind Mapping


The preliminary mind map was constructed with the prior art search of the problem statement. We considered the need, methods, sowing mechanism, error tolerance, and reason for depth variations. We also thought about the tools used in farming, crop selection, and depth of sowing.  



Prof Anil Gupta gave feedback on the Mind Map. He suggested us to include Hindrances that affect the soil, the complementary problems associated with our project like seed counting and even spacing, and the type of sensors. 



The seeds must be sown at optimum depth for higher yield and this depth is specific to the seed.


Farming Tractor Implements

  1. MB Plough

  1. Cultivator

  1. Harrow

  1. Manual Seed Drill

  1. Rotavator



Field Visits


The team went to villages around Grambharti for field visits.


Field Visit 1: Amrapur


Person met: Surendra Singh Rathod (9924510631) and his son Jayaraj (9924477831)


Q: What crops do you grow?

A: Almost all the seasonal crops. It depends on the season. Right now we have just sown cotton is one field and preparing another one for cotton. In winter season we grow vegetables like Green Chilli, Brinjal, Cabbage, Cauliflower. Other crops are castor, Jwar,Bajra, and Okra.


Q: How much is the area that you farm on?

A: 17 acres. But the land is distributed into small fields.


Q: What is the type of soil?

A: There are two types of soil here. Black soil and semi black (‘gurado’). Black soil requires less water as compared to semi black. So black soil is good during when the rainfall is less but not good during heavy rains.


Q: How long have you been farming on this land?

A: It has been 15 years.


Q: What changes have you observed during this time?

A: The yield has gone down drastically.


Q: What are the reasons that the yield is poorer now?

A: Erratic and less rainfall, pollution in the environment, diesel prices have gown up, pests that affect the crops have increased and now using insecticides and pesticides cost us higher.


Q: You said that diesel prices have gown up. Since when have you been using tractors?

A: We are using tractors from day 1. Earlier bullocks were used more frequently but now it is only used only for ‘gudai’ after the first shoot appears.


Q: For what purposes do you use the tractor?

A: First we implant the cultivator and run it on the field. After that Ploughing is done. After ploughing levelling is done. The we make furrows using ‘chariya’.


Q: How do you sow seeds?

A: Sowing is done by hand. We measure the depth to be sown by fingers and thenmake a hole by finger and put the seed in that hole. For some seeds holes are not required and we just throw the seeds on the field randomly.


Q: Does everyone in this village do it in the same way?

A: Yes. Not in this village only. In many villages around the same practices are followed. They sow seeds by hand. No one uses the seed drill.


Q: How much does the labour cost you since you are planting the seeds by hand?

A: Today no labour is ready to come. We don’t get labour very easily therefore we have to pay them higher on daily wage basis. We give them Rs170 per day which is higher as compared to other farms.


Q: Why don’t you use the tractor with a seed drill for sowing seeds instead of doing it manually?

A: Tractor cannot be used for cotton seeds but it can be used for Bajra and Jwar which we do sometimes by bullock. We don’t use tractor because we do not know if the seed has fallen or not. Sometimes many seeds fall in a single place. Also the level at which the seed is sown is not perfect.


Q: Why is the level of seed not perfect?

A: The entire field is not flat. There are variations in the terrain.


Q: What is the depth of sowing different seeds?

A: Cotton: 0.5-1 inch, Lady finger: 0.5-1 inch, Bitter Gourd (‘karela’): 3 inch, Castor: 3 inch


Q: What do you think, how can we solve the problem of sowing with tractor?

A: “Uska meter honachahiyekibeejgayakinhigaya. Agar gayatohkitnagehragaya.” There should be a meter to monitor whether the seed was sown or not. If yes, at what depth it was sown.


Q: We are working on the same problem. We are building a sensor that will tell you how deep is the seed sown and how many seeds were sown. Can we have a look at the field where cotton is sown?


Then the team had a look at the field whqere cotton was sown just a day before. It was planted on the sides of the canal. The team also saw the cultivator, plough, leveller, rotavator and manual plough used with bullocks.


Q: What crops give you the maximum profits?

A: There is no such crop. We have to grow all the seasonal crops because we don’t have greenhouse shelter. Otherwise castor gives maximum profits.


Q: What are other problems that you face?

A: Can you do something for the thresher? There is a lot of waste collected along with the useful grains. Saw dust and pebbles of the size of grain are not properly removed.  Also during winnowing the saw dust is blown away by the thresher. This gets collected on the farm then labour has to be called to collect it from ground.


Q: Can’t you just block its opening by some sort of sack?

A: We tried doing it but then most saw dust waste came along with the grain. So blocking the opening is not an option.


The team then saw the working of the thresher.


Q: Is there any machine available in the market that does this?

A: Harvester has less waste. But is cannot be used on small distributed farms like ours. It is also expensive. When we take the grains to the market to get is separated from pebbles and saw dust it costs us 70Rs for 100Kg.


Q: How much does the thresher cost you?

A: 2.5 Lakhs


Photos from Field Visit 1




Field Visit 2: Mubarakpur


Person met: Hasmuk Prajapati (9723535527)


Q: How much is the area that you farm on?

A: We h