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.
A completely new delta robot has been build for Lego World 2017. The robot is based on the ABB FlexPicker Robot. You can read more about building the Lego Version at Eurobricks.
More photos are available at our Flickr page: Flickr.com/user/siouxnetontrack/deltarobot and videos are available at Youtube: youtu.be/user/siouxnetontrack.
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.
Continue reading “Ticket Dispenser Unit (complete), version 2017”
For Lego World 2016, we are engineering a new delivery station. Some background information: in the 2015 version, the candy crane grabbed the candy directly. Unfortunately, too often the candy fell out of the grabber during the movement of the crane. Therefore, we decided to update the crane that it would pick up the complete container (with the candy, of course :-)). The crane update is already finished as you can read in our previous article. In this article, you can read about the ideas of the new delivery station.
Continue reading “Engineering the new delivery station for Lego World 2016”
A new video has been uploaded to our Youtube channel about the candy crane version 2016:
- Improved grabber
- More robust look
- Power chains
For Lego World 2016, we have planned to pickup and hand over the candy tickets using a vacuum grabber.
Continue reading “Lego vacuum grabber for picking up the candy tickets”
When building the candy crane, I was able to test it without using the power transformer (art 45517). At Lego World, because of the power consumption, it was needed that we hooked up both EV’3 to a power transformer. The cables of the transformer sometimes got into the running wheels, causing the system to fail. So, we needed to add a power chain system like this:
Continue reading “Building a power chain system (for the candy crane)”
As described in the previous post (“Plans for Lego World 2016”), the updated crane uses two touch sensors for the positioning of the hoist. In this article, I explain this in more detail.
The two sensors slide over two rails that makes sure that they are pressed or released. By this means, we can distinguish four positions that are shown in the picture below:
The numbers 1 to 3 are ‘defined’ positions:
1. Pickup position where the container is picked up from the conveyor belt.
2. Loading position #1 where the container is loaded into the train at track 1
3. Same as previous, but then for track 2.
Position 4 defines ‘the rest’, that is any position between the defined numbers and left from position 3. But note that there is no position 4 at the right from position 1. This is important for determining the starting position: when starting up the EV3 of the hoist, the EV3 can determine if it is on position 1, 2, 3 or 4 based on the state of the two touch sensors. In case of position 4, it is not exactly defined. But one thing is certain: if the hoist moves to the right, it will eventually find position 1. That is the reason that there is no position 4 at the right of position 1. Otherwise we wouldn’t know at startup in what direction the hoist should move to one of the defined positions.
So, the first thing to do when starting up: move the hoist to position 1 by moving to the right until it finds that sensor 1 is pressed and sensor 2 is released. From that moment, it is easy: if the hoist has to move to one of the three defined locations:
- if the new position > current position: move to the left
- if the new position < current position: move to the right.
And keep on moving, until the touch sensors indicate that you have reached the desired position:
- Touch sensor 1 = pressed and Touch sensor 2 = released
- Touch sensor 1 = released and Touch sensor 2 = pressed
- Touch sensor 1 = released and Touch sensor 2 = released
A demo program that randomly chooses the new position, has proven that the touch sensor readings are very accurate and that it never failed to miss a location. If you are interested in the EV3 program, please drop me a note.
The last weeks were rather hectic. Finalizing our fully automatic train layout was just like a real project: strange errors, unreliable bluetooth, confused light sensors. We had it all. But we made it! Continue reading “Sioux.NET on Track for Lego World Utrecht 2015”