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:
Power chain system for the hoist
For the EV3 on the hoist, I use the track elements (57518) to guide the power cable:
At our Youtube channel, you can see the working of the system:
Power chain system for the body, two alternatives
For powering the body, I wanted to use the same track system. But I found out that the length of the chain (appr. 75 cm) caused the chain to bend too much that it hit the ground. My first idea was to turn the chain 90 degrees:
Although it worked, it wasn’t really cool too watch (see the first part of the Youtube video: www.youtube.com/watch?v=ru3bE6_5yj8). I designed an alternative based on the older Technic bricks. I found out that two aspects are important when you design a power chain system:
- The chains should rotate as much as possible and without friction in one direction.
- In the other direction, there should be no movement at all (= to prevent it from bending)
In the second part of the video, you can see that this system works fine.
Final version of the power chain system for the body
I found the chains too large for the crane, so I came up with another alternative:
The cable that is guided through the system, needs to be fixed at both ends. If you don’t do this, the cable will still get stuck. Due to the fixation of the cable, it is always held tight and it cannot get stuck anymore. Don’t forget to bend the chain first (like in the pictures) and then fix the cable ends, otherwise you cannot make the bend afterwards 😉
The previous design is now implemented and used as the final version, you can see it working in the following video:
Can it even be more elegant?
I’m experimenting with a smaller system that I find more elegant. Also, the use of the more lightweight colors makes the power chain system also optical smaller.
I have ordered the bricks to make a chain of 36 elements in length (total length 108 studs without the bend). When it is finished and working I’ll make a video and update this post.