Modified Design of a Precision Planter For a Robotic Assistant Farmer

1-2-Seeders and Planters 
A seeder (and by extension a planter) is a mechanical system which can be attached to a 
tractor to place the seeds into the soil and cover it for germination. A planter is an accurate 

---

3 
seeding mechanism which utilizes precision seed metering system to singularize the seeds for 
planting. On the other hand, a seeder uses mass flow seed metering system; so it does not have 
the accuracy of a planter. Each of these systems has its own pros and cons. A seeder mechanism 
is shown in Figure 1-2.A complete seeding mechanism consists of the following components [2]: 

Soil engaging components 

Depth control components 

Seed metering components 

Soil packing components 

Shock absorbing components 

Lift and transportation linkage and mechanism 
To be able to design and develop a planter, a good knowledge of the components of planters 
and their function is required. A short description for each group of components and their 
different types is provided below. 
Figure1- 2- A seeder/fertilizer unit: 1) Shock absorber/depth control cylinder, 2) Fertilizer 
tube, 3) Fertilizer knife, 4) Seed knife, 5) Seed tube, 6) Press wheel. 

---

4 
1-2-1- Soil engaging component:
Soil engagement component is the tool in a seeder or a planter that is in contact with the 
soil to dig a furrow to place the seed. Two major classes of furrow openers are tine (hoe, shank 
or knife) type and disc coulter type. Each of these types requires their specific mechanism and 
has its own features. Different types of tine furrow openers are shown in figure 1-3.
Figure1- 3- Different types of tine type furrow openers 
Disc type furrow openers or disc coulters are available as single or double or even triple 
disc configurations. They open a furrow by cutting and pushing the soil to the sides. Disc 
Coulters are more accurate; they need less draft force and make fewer disturbances in the soil. 
They are more effective in the fields with large amount of residue. But they have shorter life due 
to its small thickness and its axial rotation compared to tine type furrow openers.
No-till farming is the trending method of farming since 1970s. No-till or zero-tillage 
farming is a method of cultivation without disturbing the soil through tillage. Using this method, 
farmers conserve water and soil material (nutrients) and also reduce erosion. It also reduces labor 
required for farming which will result in fewer carbon dioxide emission into the atmosphere.[1] 
Having this in mind, it can be said that disc coulters are more favorable for planting; because 

---

5 
they are more efficient in residue handling and they cause less disturbance in the soil compared 
to other types of furrow openers. Figure 1-4 shows a disc coulter which is cutting through the 
soil and residue. 
Figure1- 4- Disc coulter cutting through the soil and residue
http://salesmanual.deere.com