About this video
The builder tries Velcro on the battery packs but it does not hold, so zip ties are used instead to fasten the batteries firmly. The zip tie is looped and orientated so it tightens against the battery when pulled through. Battery placement near the centre of the bot is also explained because it balances the weight.
You'll be able to
- explain why a fastener must suit the surface it holds
- describe how to orient a zip tie so it tightens against the object
- explain why heavy parts should sit near the centre of a robot
Key words
- Zip tie
- A plastic strap that is threaded through a hole and pulled tight to fasten parts.
- Velcro
- A hook-and-loop fastener that holds two surfaces together.
- Centre of mass
- The average point where the weight of an object is balanced.
- Orientation
- The direction a part or fastener is turned or placed.
Transcript
I thought about using Velcro for doing this and actually tried sticking Velcro on the back of the batteries, but they tended to not stay very well. So as I put this in, I want to make sure that I loop it like this so that that top part is facing upward, and that'll mean that as I pull this through, it'll give it a nice, tight fit on the back side.
All right. So you don't have to tighten it down all the way just yet, but you should get it pretty tight. It should be definitely not moving around. The batteries should be pretty firmly planted in their location. Yeah. That's pretty good there. All right. And we'll get the other one through.
And again, we want to orient everything the same way just because if you put the zip tie the other way, it will not sit tightly against the battery. All right. It's fairly important when you mount the batteries that those are in the center, or pretty close to the center of the device, because it's where most of the weight is.
So when you need to take these out, you can press it over to side and pull the batteries out. It's not super easy, but it'll hold them pretty well, and it's fairly, like I said, inexpensive. OK, so once you've got that pulled to a level of-- you want to make sure it's really tight, because that plastic will loosen over time.
And just cut it off like that.
Video © Khan Academy, used under CC BY-NC-SA. Watch on Khan Academy. Puzzicle is not affiliated with Khan Academy.