Oscilloscope Diagnostics for Signal Troubleshooting | Marvelmind

0:02 Hello colleagues. So this is a demo about using an oscilloscope. Embedded oscilloscope can be found here and here. So these two are very powerful tools, and they are used in order to check the strength and quality of the ultrasonic signal between the beacons, and in general monitor their background noise. If you have a very noisy background, so what you do, you go to View, you go to Oscope, and then you select the beacon which you're using for testing and signal from Beacon. So now beacon number five emits ultrasonic sound, and beacon number four is receiving. So this is a very good signal as you see. My beacon number four has a distance to number

0:59 five around 4 something meters, precisely 4.7. You see 4.7 meters. So this is how the signal looks. If I want to see how in the opposite direction, so I simply press here. So this is my opposite direction. They are virtually the same. So signal from number four to number five, and this is from number five to number four. If I want to monitor, for example, number five, so I can easily go to number three. Okay, the picture changed as you see. Now it's not so great because for some reason the direct path is pretty weak. So for example, if I choose now the threshold hold on level eight or 800, it would be very problematic for me because my threshold would trigger somewhere here or here. So in this case it will be wrong.

1:57 I better choose threshold on the level of 200 or 300. In this case, this will be triggering my first real one. But in this case I would rather check why is it so. There is either an indirect path or something. So there must be a reason why the signal, which is not direct, it's rather an echo, much stronger than the first signal. This is a good indication that you can monitor, and should monitor, the signal. For example, I may try even to choose different settings here. For instance, number three—I don't know, it's not clear—but I may choose, for example, to deselect some of these and leave only one left. So in this case you see the signal increased significantly. So because my RX1, RX2, RX3, and RX4 did contribute,

2:57 to the signal strength. Now the signal is improved. You see, the signal is fluctuating because automatic gain control automatically adjusts the signal. But now the signal is much better because the direct path is now a good one, but it doesn't receive the echo from somewhere. So it's very good to check when you have a problem. For example, the table is not wide or you have some concerns, you just go to the Oscope and select the beacons or select the sensors which are useful and receiving the signal, and deselect those that are not needed. Notice once again that there's yellow. Yellow is not a problem. Orange is not a problem, simply because it indicates that settings of beacon number three and settings of other beacons are not the same. So if I return this back, they will become green again. Okay, now the system adjusts the gain. So it takes some time, but all of

3:55 this is green. So it's also useful when you have, for example, the map frozen, like in this case. The map is frozen. Now you could enable, for example, the Mobile Beacon. But you see the Mobile Beacon is jumping in some area. Not a problem. Just install the Mobile Beacon on the tripod, set it in that problematic area, and once again, go, for example—I can set now there on freeze and I can choose beacon number four to be, oh sorry, to be active, the Mobile Beacon. So now it's Mobile Beacon. I have a map consisting of two beacons. It's a 2D map. I can freeze it. Now mobile beacon four, even though it used to be a stationary beacon, now it's a mobile beacon. And for example, I have concerns about mobile beacon four. Okay, so I can easily check. So I select beacon number four and check how the

4:54 beacon number four is seen by my stationary beacons. So this is how my stationary beacon three sees it. Okay, sees it pretty well. So automatic gain control keeps the gain very low, but you see there's almost no noise, and it automatically chooses the threshold. I don't know where exactly, but I guess somewhere here. And beacon number five sees it, okay, also pretty well. So now, okay, it's an easy map, an easy situation, signal is clear. So this is the echo, but my first signal is here. So in this way, if you have a problematic area, just put your mobile beacon in that problematic area, select the Oscope from here, and then check the signal quality. And if the signal quality is not perfect or your threshold is not optimal, play with the ultrasonic threshold. Move it instead of automatic. And here, automatic

5:54 to manual. Select anyway. So for example, the threshold for this would be between probably 70 or maybe even less, up to 300. So there's a pretty wide range of threshold here. As you see, minimum threshold is 50. So probably it keeps on 50 because the noise is so low that it can be as low as 50. That's it about the Oscope. We have another one, which is a channel oscilloscope, but it's more powerful, and let's discuss it in the next video.