Session 7 - Robot Movement | iBot Summer School 2026

[00:00:51]Hello. Hello. Is this audible?

[00:00:54]Is this audible?

[00:00:57]Oh my That's fine Hello.

[00:02:49]Hello.

[00:03:15]Hello.

[00:03:22]Hello.

[00:03:24]Hello.

[00:06:35]Hi.

[00:06:37]There will be a 1 minute there. It's a slight delay. So, I'll try to manage So guys, can you can hear me right?

[00:07:42]See you, bro.

[00:08:15]Anyway guys, can you can you guys hear me right? I want to know Fine.

[00:08:55]Is there any issues on the screen?

[00:09:18]Um, guys, is the stream better now?

[00:09:50]Uh, is it better now? Audible.

[00:09:56]Okay, I guess we're going to do this without a webcam.

[00:10:01]Okay. Okay, guys. What do you think?

[00:10:04]What do you think of robot mo movement and control?

[00:10:12]Hello.

[00:10:20]What do you think about movement and controls?

[00:10:38]Let's go. Okay. If you look at a robot, how do you think it moves? How do you know how to turn it properly? You there is motors, but then how do you know which speed to go at and everything? And then how does it like accurately judge where where it needs to go? Like if you want say tell an robotic arm go to I don't know some 2a 3 in that in this place 2a 3a 5. How do you think it goes to that position accurately? Or like if you tell like the vacuum robot, the Roomba, it needs to go straight, right?

[00:11:19]Not only straight, it needs to like go through the whole house and then map find out every place. And how does it know where to go? How does it calculate where to go?

[00:12:12]Hello.

[00:12:58]Yeah, robot movement and control basically this is is all about having finding how to move a robot figuring out how where it is in the map find and then trying to go to the accurate location accurate location.

[00:13:17]So yeah, let's start. Okay, first of all, we need to know what motion and pose is. Okay, motion I guess you I guess you guys know what motion is.

[00:13:26]Motion is when motion is just the movement of the robot. How are you moving the robot? How fast it's moving, how fast it's turning. That is what motion and pose is. And position pose is just a combination of position plus orientation. it. We need to know where on the map or where on the floor or wherever the robot is. We need to know where it is plus which direction it's looking and like how it's oriented because this will all change.

[00:13:59]Yes, but then how do you control speed and stuff? We were against P in the previous sessions.

[00:14:28]Not much. Okay. body can someone like tell me what P were taught just it's a way to control right was was in the previous sessions did anybody teach you P control Okay. Okay. Guys don't know about control. Okay. I guess we should I should looked into that. Okay. Anyways, basically uh yeah, we we need to know where the pos where you're looking at. P is just a way to control where you need to go.

[00:15:23]Yeah. It's a feedback loop. Correct.

[00:15:26]Yeah. Yeah. Okay. Yeah. You guys did turn and right. So you guys know the position and then how to turn to the correctly to whatever angle you want.

[00:15:34]Yeah. That is P and that's it. And that is position and motion is uh this one.

[00:15:39]And when you start motion you need to have like a frame of reference, right?

[00:15:43]You need to know something which is some position which is already known.

[00:15:50]Yeah. Usually we have three different types of references.

[00:15:55]Uh basically the first one is the world reference basically that's like the origin of your ground. Yeah I'm going to come to that the origin of your ground like this is where all the coordinates will start from this your origin. this this frame will not move. This reference will not move.

[00:16:14]And yeah, there's another one is robot sensor and the robot frame and the sensor frame. The diff I'll tell you what's the difference. Even though they both move in the same place, the robot frame is where is like the origin of the robot. It's where the where the center of mass of the robot or all the velocities act on. So if you say go at like I don't know 2 m/s this point we consider this point to be moving at 2 m/s not any other point and sensor frame we don't give we don't tell anything to this sensor frame will give like the position let's say the sensor is some LAR okay you guys know what LAR is Good.

[00:17:13]Yeah. Okay. Now, lighter.

[00:17:16]Um, it'll give you the distance from Yeah. Now, you know distance, right? Now the the sensor will give you the uh distance from the object towards itself but we need to we need to find the distance from it to the robot not to the sensor the sensor can be anywhere on the robot but then in but it's not on the center of the robot right so this is the this why we have a third frame of reference we just get the distance from this and then convert that to our robot frame reference it's just like shifting origin so that we know where it is or like shift it to the world reference so we know the exact position of the obstacle or like whatever it's trying to whatever distance it's trying to find any doubts also guys there's a 30 secondond delay between me speaking and and coming on the stream so there will be so please like adjust be considerate of that if there's some silence for a long time.

[00:18:20]It's probably because I was waiting for you guys on the chat.

[00:18:44][snorts] Okay. Is it buffering still?

[00:19:45]working.

[00:20:01]Please say something in chat if you can hear this. Hello