Weed Cultivator Modification
By: Rishabh, Riya, Dhaval, Alpesh, Aditya and Bharat
May 2018
Introduction
In farms where crops are grown is linear (rows and column) pattern (as shown in the figure below). Different crops have different width and in the space remaining between two crops, rows/columns are occupied by weeds. Which needs to be removed from time to time so that it does not harm useful crops. Specifically, for the crops which are short in length (vegetable crops, eg. brinjal) so that the tractor can be used to plow and also for removing time to time.
For removing weed we do not need very massive cultivators which we need in plowing the field, it is also a frequent task for farmers (daily, weekly). The more weed is removed daily the more better crops will be there and so production.
Field Visit
To know the actual problem present we went to nearby village in Amrapur and had some discussion with local farmer and Kuldeep sir (who also has his own field). There we got to know farmers may grow different crops in a season at a time in different area of fields. The width taken by a crop row will be usually different from second crop. So the space and position where weed grows by itself will be different.
As the cultivator used in tractor is very heavy (in fig.)
Also if we see the nut and bolts for tightening in different slots (in fig.) is robust and heavy. So for different crops position of the blade arms has to be changed, which is a tiring and time consuming worAs the cultivator used in tractor is very heavy (in fig.) Also if we see the nut and bolts for tightening in different slots (in fig.) is robust and heavy. So for different crops position of the blade arms has to be changed, which is a tiring and time consuming work. It takes around 20-30 minutes to reposition all the blade arms. Also if rusting is there, that makes the work more harder.k. It takes around 20-30 minutes to reposition all the blade arms. Also if rusting is there, that makes the work more harder.
Problem Definition
After lot of discussion we came to our problem definition: “ To design a mechanism to easily reposition the blade arm in tractor cultivator used to remove weed. ” Which will reduce the time consumed and effort required and also should be user friendly.
Sketches and Cardboard model: We Came up with two ideas: 1. The first idea was taken from Trowel (Khurpi). All blades will be connected by nut bolt mechanism, for changing the position of one the blades just loose the nut, change the position (rotate it around the connection) and tight it again.
We also made a cardboard model for that.
2. In this design, we have taken the idea from the actual cultivator itself. Here we have just made a modification in positioning the blades. Here we have used a slider mechanism for moving the blade support.
Prototypes
Prototype 1:
The working of the prototype is as same as explained above for first idea in sketches. Just simply rotate the blade arm for changing position of blades by loosening the nut and tight it again.
The limitation of this model is that this can be used for small change in blade position otherwise the blade orientation will be changed and it will not face forward which is necessary.
Feedback:
As told by the expert there will be strength and stability problem in holding all blade arm with a single nut bolt mechanism.
Prototype 2:
As explained above in second sketch design, we did some modification in existing cultivator. We thought of slider mechanism to change the position of blade arms, which will be easy for the user. Since the problem was the reposition of blade arm frequently by opening nut and bolt from one slot and fixing it to other slot.
Here the blade arm is connected to slider, slider can slide on support frame. One extra advantage of this design is that slider can positioned at any position and so blade arm. The working is simply loosening the bolt of slider, slide it to desired position and again tighten it.
Feedback
The design was appreciated by people but only problem present is strength again that would it be able to work as the existing design is made so robust and heavy ( blade arms are fixed in slots and tightened with nut and bolt).
User Testing
Due to lack of time we only made the prototype (small version) and were unable to taste but response of experts/professors, I have mentioned above.
Way Forward
As the response was obtained from the people, we will try to work on that. Testing is yet to be done which is very important , so that actual response and experience of people can be taken, which will decide the future work on proposed design. We will try to work on strength problem, also take some suggestions from industry experts. We are excited to improve the proposed design and existing product.