diy cacao tool
This site shows my humanitarian and social design portfolio. I do process design, so optimisation of social and humanitarian processes, through system design and product design. I strive for Efficiency of humanitarian actors, through a needs based approach. I research, teach and talk about that.
humanitarian, process design, product design, social design, Frankfurt, international, German design, humanitarian Innovation, Germany, Human Centered design, community centered design, Thomas Jäger, design portfolio,
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A harvesting tool that protects the farmers and

secures the quality of the harvest

While developing this project with small cacao farmers, I witnessed firsthand the labour intensity of this work and the little financial benefits the farmers get. Furthermore like in many sub-Saharan countries the access to medical services is limited. Contrary the work on the plantation isn’t. These aspects are partly based on the availability of adequate tools for the harvesting process. While picking the fruits with a common cacao knife the farmers often cut in the bark. This allows parasites to enter the tree organism, if there are no toxic pesticides applied, and potentially leads to the tree dying.  Looking at the fact, that a cacao tree needs to grow four years before it produces its first fruits, this leaves a huge economical hole.

After the fruits got picked, they need to be opened. Commonly this is done using a machete, which even for skilled workers brings the danger of cutting parts of their hands, in a context where there is no medical service available.


The “DIY CacaoTool” is a project that was developed in cooperation with Bösöppe e.v and the Ministry of Agricultural of Equatorial Guinea. The aim was to make the cultivation and farming of cacao more efficient and in line with permacultural methods, to improve the economic well-being of the farmers.

During the cacao harvest three key problems are encountered that impact worker welfare and the economic prospects of the harvest:

  1. The cacao knife used to pick the cacao from the tree often damages the bark. This results in pests infesting the tree and making it unusable for future harvests.
  2. After the fruit is picked, it is opened with a machete. In this process, the workers often injure themselves. There is no medical care on the plantations.
  3. When the fruit is opened by these means, the “cacao nibs” get damaged. This reduces the quality of the cacao nibs and decreases the price, resulting in lower income for the workers. The tool here is the solution to both problems. In a participatory process on the plantation, a geometry was developed that keeps the blade away from the bark for picking. 

In addition, the basic conical geometry lends itself to efficiently opening a fruit with the opposite side. Since no blade is used, possible damage to the “cacao nibs” and also to the user is greatly reduced.

The setting and aim of
the overarching project

This tool development got initiated in an overarching project. Bösöppe e.V., the University of Art and Design Offenbach am Main and the Agricultural Ministry of Equatorial Guinea established a cooperation to make the long-time undervalued field of cacao small farming more attractive to work in. This way the project aimed to deliver professional opportunities to the citizens of Bioko island.

The project took a holistic approach and developed a way of distributing the products, creating new products, making the actual work more appealing, and connecting the small farmers. The first step got developed in Offenbach, consulted by Bösöppe e.V. and then further on-site with the farmers.

protecting the workers

The work on a plantation is labour intense, creates little financial income, and is partly dangerous, even for skilled workers.

The main danger in the process got identified as the step of opening the fruits with a machete. Most times the skills of the workers allow them to do so without injuries. Nevertheless, when they hurt themselves the wounds are grave. Partly they cut off entire fingers. Due to their income and the setup of the medical system, they are mostly left without adequate care for the wounds, which then can result in long-term disabilities.

Who would endanger themselves like that, for such a little income, if any other choice is given?

securing the quality
of the cacao-nibs

The actual product of a cacao plantation is the cacao nibs. These get fermented, roasted, and further processed to e.g. chocolate. Based on the quality of the nibs the framers can achieve higher or lower margins for their harvest. The cacao grown in African countries is due to the climate already disadvantaged to the cacao produced in South America.

The quality often gets further compromised by the workers and farmers themselves during the harvest process. Using a machete opening the fruits often leads to cuts in the nibs which lower their quality and makes them unusable for high-quality cacao products.

protecting the trees
and four years of

Commonly cacao is picked from the trees, by using a cacao knife. A thin, hook-shaped blade gets attached to long sticks, often made from bamboo.

By wrapping the hooked blade around the stem of the fruit and pulling it down, cuts the stem and the fruits drop to the ground. Because of the huge height, it is difficult to clearly see where to cut exactly. This and the geometry of the cacao knife often leads to cuts in the bark of the tree. This, as long as not countered by toxic pesticides, leads to parasites entering the tree, which then potentially dies. A cacao tree needs a minimum of four years of growth before it produces the first usable fruits. Therefore not applying pesticides to the trees would equal a loss of four years of investments.

Shifting from
pesticides to

Pesticides are one way to keep the trees alive. But it comes to costs. Firstly the farmers harm their plantations‘ ecosystem. Secondly, they endanger themselves through breathing in the toxics, which they even need to pay for. Thirdly, it closes the window of opportunity to market their harvest as organic and high quality for them, even though it could create huge financial benefits for them. Shifting to a more ecologically sustainable form of agriculture is just able through providing different ways of dealing with the trees‘ sensitivity than applying pesticides.

A spreading geometry replaces the machete and
protects from the knife blade

While creating the first solution ideas with Bösöppe e.V., the research has shown that the most native way of opening a cacao fruit is nearly as quick as with a blade and totally safe. People just hit them on an edge till the shell is cracked open.  There was no usage of a blade at all involved. Adapting this way of opening such a fruit into an applicable tool was the main idea. Producing a hermeneutic prototype in combination with further research also highlighted the opportunity to combine the process of opening the fruit with the process of picking it, embodied in that tool.

Dividing the tool into two sides, one for the picking and one for the opening allowed this combination. The side opening the fruit had a basic spreading geometry instead of using a blade. The blade needed for the picking got kept in distance to the bark again through the spreading geometry.

The user-lead co-design
process, through prototyping

Pre Producing such a prototype allowed firstly to try out its functions before arriving at the plantation, verifying its potential usability.

Furthermore, it allowed communication in an intercultural co-design process. Instead of explaining the different ideas to each other, the users and I were able to show the ideas with the prototype and also try out the tool. By this means concrete demonstrations of improving it were possible. This also leads to one farmer community member grabbing the tool demonstrating it to the other workers and getting their feedback. I was in this case just observing.

On-site improvement
of the prototype

This participatory process leads to another way of communicating improvements and ideas. We, by means of me and the farmers, sketched directly on the plantation. In addition to the demonstrations, this allowed further thinking about the prototype and a more detailed exchange.

workshops with the wider community lead to the DIY

Introducing the project to the wider community of Bioko, we ran workshops and presentations in the community center of Malabo. There the children of small farmers gave their input to the tool, identified weaknesses as the weight, and made suggestions on improvement. Having the time and a surrounding to develop thoughts away from the busy plantation created a holistic look at the innovation. There we also spoke about ways of implementation. To the participants, it seemed most promising and applicable to enable people to create the tools themselves. This would allow the production in cooperatives, potentially create an additional income for local metal workers, and secure the accessibility for low-income communities.

The Tool

The tool’s purpose is a double trajectory. It is used to pick the fruits and open them as well. Each gets represented by one side of it. The side with the blade similar to a common cacao knife is used to pick the fruit. The other side with its pyramid-like geometry is used to open the fruits.  Its geometry is designed in a low complex way. This in combination with locally available material and a simple and quick assembly through welding allows the local production in nearly every context.

Opening the fruits

To open the fruit, the users use the side of the tool with the mandrel and its spreading geometry. Simply punching this geometry two to three times on the hard shell cracks it open, so that the nibs can be taken out. The nibs are in this case not hurt. The geometry, in case of it being punched deep in the fruit, pushes them to the side.

picking the fruits

The side with the blade is used to pick the fruits in exactly the same way as commonly done with a cacao knife. The difference here lays in the placement of the blade between the horizontal parts of the opening geometry.

The blade is kept in distance to the tree hindering it to cut in the bark.

local adaptation

To secure the possibility of the implementation the focus of this project was exclusively put on the tools head. This left questions to answer to the cacao farmers to answer themselves. What stick is the best? How are we going to store it? and similar questions can vary from user to user and context to context. This is why the cacao tool provokes local adaptation. The users have the capacities and capabilities to adapt the product to their needs. Furthermore, they know the infrastructure and their own work the best. This is why they have the expertise to answer these design questions.

A basic geometry published Open-source

At the end of this second step of development, a basic geometry was designed, that was practical and useful, and locally producible.

This geometry then got shared with institutions on-site and building instructions got published online, allowing users to adapt, modify and improve the tool. A design by doing process evaluating the local parameters constantly new was the result. This way of implementing solutions also secures that the design fits the user’s needs and lets them take ownership over the project.

Implmenting the tool via publicly accesible instructions

The website „“ went online in 2019. It was a one-page design, that even little computer literate people were able to access. Furthermore, it got decided to set up its own page to secure access in countries, where there are access restrictions. The main section of it was a building instruction, based on visual communication. There was no written word included, allowing the spread internationally.

Further education concerning the tool

Another section included in the website was concerning the overall improvement of the work as a cacao small farmers.

This section highlighted different ways to do so. Creating adequate work surrounding for the workers, creating more income and cooperatives, and working more ecologically sustainable got put in relation and therefore clear to the visitors why investing in that, what part the tool plays in that and how to look at it holistically. 

Here there was written text included to describe these matters in detail.

Accessing the instructions
by phone

Being aware that the main target group of users was low-income communities, lead to a responsive one-page design. Low-income communities or people in a replacement setting often only have their own mobile phones to access content online.

The responsive design, transformed the desktop view to a practical visualization on the mobile phone, without using a different code.

product improvement
through little effort
open source

On the phone, people were able to take pictures of their modified tools describe the adaptions done by them, and upload them to the cloud, where other users had access to it.

The quick process of using the phone and its camera lowered the efforts needed to share the adaptations and encouraged people to do so.

Some needed improvements got obvious through the consultation of the users:

Especially while picking the fruits the weight of the tool, made the work difficult. It needed to be nevertheless compromised by the weight needed to easily open the fruits.

Also, the instructions concerning the assembly weren’t clear to everyone and needed further improvement.

The main geometry even though functionally and practical working still showed opportunities for improvement to make the work even quicker and easier.

It also got highlighted, that in some areas not even a basic welding tool is available. Therefore suggestions were made to potentially come up with a further development that eliminated as many tools as possible needed to create the tool.