In this episode we continue from Episode 55 and we improve the durability and stability of the attachment for a LEGO Mindstorms EV3 robot. Many times attachments are not very stable which results in gaps between parts. The goal of the video is to give basic construction ideas.
- 23 Oct 2014
The previous Episode 55 introduces the basic idea of changing gears orientation from vertical to horizontal. In this episode we stop at some of the principles of improving the stability and durability of the construction.
Instructions for building the robot:
- Available at Episode 58 EV3 Competition Robot Construction
Building instructions for a LEGO Mindstorms EV3 active attachment for changing gears orientations. This is the second attachment from the series.
In episode 55 I showed you how you can change the direction of a vertical wheel attached to the front of our robot to a horizontal wheel. And we built an attachment. This attachment had some problems and it was not very durable so in today's episode we'll see how we can improve this attachment.
First, let's start from where we stopped last time. This here is the attachment. We place the gear wheel here. Then we can place the attachment on the robot.
Now we have the attachment working. When the gear is turning, the other gear is also turning. The problem with this attachment is that when we place something to the front, something that's heavier, the gears will no longer work together and there will be a gap between the gears. For example, I will now start it. If there is a heavy load on the front, the gears won't be working together. We should find a way to improve this. One of the first things we should do is to find the problem. The problem is that the attachment is attached to the robot at two points only. And the connection is not very strong. So, we can improve this in several different ways. Let's start with something very simple. Let's attach these beams not only to a single point but also to another one. We could use these parts and we could do something like this. It's very simple. Very straightforward. Again, we start the robot. We can see that the attachment is much more durable and even if I press it and I try to press it even harder, it will continue working. So, this is one of the ways you could improve this attachment. The problem is that it's kind of difficult to place it, it takes a lot of time. If I have only the attachment and if I want to place this attachment on the robot, it will take me something like 1, 2, 3, 4, 5, 6, 7 seconds. It's not good enough. We could improve the time by simply removing two of the small black parts. This one here and this one here. And change them with parts that will make it easier for the team player to place the attachment. Now, let's try to place this attachment on the robot. It will take us 1, 2, 3, 4, 5 seconds. And the attachment is ready. (No, it's not.) So, again, it takes about 5-6 seconds to build the attachment. One thing we should also consider is that we should improve the stability of the attachment
by using the upper side of the robot. For example, by using these two holes here. Let's see how we can do this. This here is our attachment.
We see that it's working - not very stable, not very durable but at least working. So, we could use a construction like this - a module like this; place it on the top of the robot and now we could find ways to attach the attachment to this construction. We can do this in several different ways. I have prepared some parts. You can see the constructions in the video. But if I add the parts like this,
they are still not connected, so the first upper construction module is not connected to the attachment. We can connect them by using beams. I have here 7-hole beams. I will just place the beam on the sides of the upper construction and we could connect both of them. It takes some time. And I'll do the same on the other side.
Again, the construction is working. Now it's much more durable but, again, you can see there's a certain gap. This gap comes from here as we've connected both the attachment and the upper module with only one black part. As a result, the whole construction is not very stable. Another way we can improve it is to find ways to connect both constructions at at least two points. I'll remove this. I'll remove this as well. We could use 5/3 beams and attach them because the 5/3 beams will connect the upper construction and the attachment at at least two points. The whole construction will become much more stable.
Again, it is working. And it's very stable. Even if I apply a lot of pressure, the whole construction is very stable. The problem with this construction is that it will be very difficult to place it on the robot. And it will take probably a lot of time. Here's the construction. If I try to place it on the robot, it will take me 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 seconds. 11 seconds is not very good for the competition. And again we can use what we have learnt in the previous video - We could use these parts - the red ones.
I'll remove both black parts from here.
One and another one. Place the gear wheel. And now, placing the attachment on the robot will take us like 1, 2, 3, 4 seconds. In four seconds our attachment is working. You can find the instructions for the attachment here and in the next video we'll improve it even more.