Espresso machine

Improvement on efficiency –

Since the espresso machine is turned on for a long time every day. This is being noticed on the electricity bill. I think the power consumption is high because the boiler is not insulated. therefore this project is to test en isolate the espresso machine.

To test the current power consumption of the machine I made a little circuit to measure and log the current.

With another circuit I measured 3 different temperatures within and around the machine.

The circuit is made with a few resistors and sensors added to an Arduino, the Arduino is powering and reading the sensors. The Arduino is connected to a Raspberry Pi for the logging. The Raspberry Pi stores the data from all sensors  every 10 seconds in a csv. This is a plot of the data.

Temperature  (degrees C) with the power consumption (watt/100)

After logging the data for more then 40 days I have insulated the boiler with a special material. This material I got from

The standard espresso machine without any insulation.
Now I have to gather new data with the boiler being insulated.

To be continued!


autonomous vessel 

– The project I worked on since 2016 is being called the Delfia 1* (Delfia One Star). This is a project I worked on for Delft University of Technology, Faculty of 3me department of Marine and Transport Technology. The Delfia1* is a small vessel with multiple sensors and propulsion possibilities. The vessel is developed to sail around fully autonomous. The purpose of this vessel is to validate and test algorithms designed by the department.

The Delfia1* in action and promoted by Professor R.R. Negenborn

In the second quarter of 2016 I started the project after the year before I made a simplified prototype (Delfia1) to test the working principle. In this version (Star version) I changed the complete vessel, added multiple sensors, changed the layout and improved the overall design. The vessel is designed around two propulsion units, called Schottel Drive II from Graupner. The low level computing power comes from a Arduino Mega and the higher level computing is being done by a RaspberryPi3. All design of the vessel is done by myself in SolidWorks, ranging from drawing of existing parts to developing the complete hull from scratch and the sheet metal parts.


Development of the hull

The hull is 3D printed after a very rough start. I encountered multiple problems printing a large waterproof product in fairly high resolution. At first I tried to have the vessel printed by external companies. Although most companies were confident on being able to print the hull in good quality the results were appalling. See a few of the products I received from different companies (not to be named).

Somewhere within the printing the product has shifted resulting in separated layers, finally resulting in a mesh of wires.

The second product I received broke in half after trying to remove all the inside support material.

One had a horrible surface finish.

Another I got had a problem with filling up the surface and therefore there were holes in it, not being waterproof was one of the obvious problems with this print!

Another I got had a very strange build of the sides of the vessel. It more or less was waterproof, but quality was not perfect.

Similar to ordering prints from external companies I bought a printer capable of printing the full hull in one piece. The company helped me with the printing and was able to deliver one hull in good quality (with a printing time of almost 100 hours), unfortunately this printing debacle costed me about 6 months before I got 1 usable print. After that I needed 4 more. But sadly the company that provided me with the first print was not able to reproduce this more than once in good quality. Then I started to try to print this hull myself. After a about a month and many hours waiting for the printer to produce a test pieces I got a print that was good enough to reproduce.

The hull has been printed with PetG with a layer thickness of 0.2 mm and took 38 hours to print. I used PLA as support for the overhanging surfaces. I added an epoxy coating to the outside surface of vessel to it smoothen out. After sanding the hull has been painted with special waterproof boat lacquer. The result is very satisfying.

Printer at work

Printer finished.

Surface finishing.

Development of mounting plate

The front and back of the vessel is the same (mirrored). It has two schotel drives to be able to move in any given direction (even able to rotate around its center). The schotel drive is a propulsion unit that is able to propel the water in 180 direction. I changed this part so we are able to rotate it 360 (actually unlimited). I used a steppen motor and a DC motor respectively to rotate and the propellor. There are a few sensors detecting speed and power used. To fix all the part I designed a sheet metal part. This part has been laser cut at the University from 1.5mm aluminium.


Two subassemblies inside the vessel.

Inside of the vessel

One of the demands of the Delft University of Technology is to have the vessel to be as small as possible. I tried to have all components in the vessel and off course without sinking it! On all sides the vessel has multiple static ultrasonic and infra red sensors, at the front there is one HD camera (e.g. to detect signs or visual commands) inside there will be a HD gyroscope with GPS. All these sensors need to be connected by wires, unfortunately. Although I tried to structure the cable trees and loose wires, for the untrained eye it still looks like a mess.

Finished product

I produced 5 vessels to start filling up a fleet. When the software is ready (done by the department themselves) we are able to fully test the vessel also in cooperation together with the other vessels.

The first delivered vessel have been shown on different events. The Delfia has been presented to the Dutch minister of transportation, Melanie Schultz. At the Green Village the Delfia had its own stand. And the vessel has been presented on multiple other events.

History on the Delfia.

The first vessel I created was a prototype to validate if the idea was worth developing. This vessel was designed based on a catamaran shaped hull for stability with two 360 rotating propellors. With this prototype the TU Delft was able to test their simple algorithms and the conclusion was clear: the project was viable!
Here a video of this first prototype in action (vessel autonomously following a given path):


for Delfia1*

– To move the Delfia1* to different locations the Delft University of Technology asked for a high quality and sturdy case. I designed and fabricated these Flight cases to fit multiple vessels at once.

I designed two different cases. The first case contains one vessel including a space for the battery charger.

The other two cases contains two vessels at once.

The cases are made from aluminium combined with plastic and wooden inserts.

The inside of the cases are fitted with foam to make sure the vessel cannot move and will stay in one piece during transportation.
Off course the outside of the cases have hinges with a lock, bumpers, and a handle.

Within the case there is an extra space for a charger, some cables a wifi router and other spare parts.  (bottom on image)

The two types of flight cases made.

Plant pot

for home grown vegetables

– These have been made from “Steigerhout” (scaffolding wood). The inside has a water proof cloth and a drainage system has been made from PCV piping.

Not too fancy workbench

Me at work

Drilling a hole for the drainage

Filled with water proof cloth (black) and the dirt

Being in use on the balcony.

Since there are three different pots, the layout can be changed off course.

The wood will change color over time and blend in with the rest of the wood on de balcony. It will “grey out”.



Garbage bin

repairing and repainting of a Metal bin

– Since we are expected to divide our garbage in different sections I also need to have another garbage bin.
The bin I have at the moment is a very old one, that has been fixed and painted by my father in his student time. Now I found another bin that looks like the one I have. But needs some DIY.

How it looked when I got the garbage bin

The one on the right is my old garbage bin

The new one needed some good cleaning with a angle grinder

Also the handle was very rusty

The top of the bin has been cleaned fully since the paint was so much gone.

Also the side of the bin has many places where it needed to be cleaned to the rough metal

After the cleaning a transparent base and anti rust coating has been applied

Then a base coat / primer and the first layer of paint have been applies.


If you have one of these, or have found one in a shop, please contact me, I still would like another one like these!!