The Container Spiral Storage – The making of …

The Container Spiral Storage finds it origin during one of the test runs. We ran out of containers at the trebuchet. In the pictures below, you can see the conveyor belt that transports an empty container to the funnel. The funnel catches the candy thrown by the trebuchet and drops it in the empty container.

This conveyor belt is able to store 8 empty containers, you can see below the conveyor belt with a row of six . To the left there is a bit more empty space, but this is where the table ends.

To the right of the conveyor belt (which is the bottom side on the picture), there is some more free space. One of the team members was asking for more container storage. While pointing to the empty space, he asked me to extend the conveyor belt with ‘some sort of spiral’. “Just build something simple”, he said. And I took the challenge.


I liked the idea of building a spiral. It needed to be something in the same style of the already existing conveyor belts, as can be seen on the previous photos. This was the first prototype of the container spiral.

As you can see in the video, the container runs easily downhill. Even so easy, that I needed to create a rail on the outer side of the spiral to prevent the containers from tumbling. The picture below has been made in Studio 2.0. Not only to create these amazing renderings, but also to count the number of bricks needed to build the spirals.

As you can see in the renders, the colors were matching with the already existing conveyor belts: the rollers black/red, the supporting structure in light bluish gray and the borders also red. The gears are all in light/dark bluish gray.

The spiral would consist of one and a half circles, making the tower +/- 30 cm in height. It would look something like the picture below.

As you can see in this picture, the motors haven’t been designed yet. I planned to insert them in the physical version once the spiral was build. An EV3 brick has 4 motor ports. Every half circle would be driven by one motor, and the fourth motor would drive the straight part that connects to the existing conveyor belt. That was the plan.

The next step: looking for Bricklink sites to buy the needed bricks.

But that was easier said than done ….


I will come back later on the difficulties I encountered while searching for the needed bricks. First, I want to give you an update about the second part of this build: the elevator.

Besides the spiral, I wanted to create a stack of containers. The stack would contain at least 10 containers, dropping them one by one (on request of the trebuchet conveyor when almost empty) onto the spiral rollers. My plan was to add this elevator to the start of the (extented) conveyor belt as shown in the following sketch:

It took me three prototypes to find a solution that would work, this is shown in the following video.

Because the containers are rotated 90 degrees, the total height would be around 60 – 75 centimeters. That would make the structure not very stable, especially when it needed to be transported. So I decided to look for a way, to revert the movement from a downwards dispenser, to an upwards dispenser.


(Almost) Final version of the new container loader

In the video, you see the (almost) final version of the container loader. The only thing that is missing, is the power cable carrier.

What is new in this version (apart from finishing the build)? First of all, it has been added to the ‘real’ conveyor belt (you can see the enormous length ;-). This conveyor belt moves the containers from the warehouse to the wagons.

Furthermore, an ultrasonic sensor has been added at the top of the super structure. This ultrasonic sensor detects if a container has passed under it, so it ‘knows’ that after 1 second it can set its state to ‘container delivered’. Without this sensor, the only way to ‘ensure’ if the container has been loaded, was to use a predefined time frame. A predefined time frame has two major drawbacks: you need a very long time to make sure that the container has arrived. And you can not guarantee that the container will be delivered, no matter how long you define the time frame. You can see the ultrasonic sensor detection in close up around time frame 0:45.

Pneumatic compressor for the 6-axis robot arm with auto start/stop

The grabber of the robot arm is opened and closed by pneumatic pressure. Therefore, I needed an air compressor that can generate a pressure of approx. 20 – 30 Psi. But how do you manage this air pressure? If the motor keeps running, the air pressure becomes too high. If you switch the motor on and off manually, you need to stay alert and watch the manometer if the air pressure doesn’t become too low. The solution: build an automatic start/stop system. In this article you can read how I achieved this.

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How to? EV3’s in Daisy Chain mode plus WiFi

If you have two or more Lego Mindstorms EV3’s in daisy chain mode, it is not possible to use a Wifi connection with the EV3 as well. For our project, we need this functionality. Two embedded software engineers in our team are now updating the firmware to make this work. But are we going to be in time….? From a project management perspective, it is always wise to have a fallback scenario. But is there one….?

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Sioux.NET on Sidetrack…. something completely different

Within our fully automated train project Sioux.NET on Track, we are starting a new sideproject called Sioux.NET on Sidetrack.

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Ticket Dispenser Unit (complete), version 2017

As you can read in the first article about the Ticket Dispenser Unit (click here for the article), the version for Lego World 2016 a ‘fast build’. Nevertheless, it worked almost flawless. Almost … sometimes the card was not transported to the end. With just some small modifications, it works even better now.
Ticket Dispenser Unit (LDD)

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