Hello, I have 3 anchors,2 tags and 1 Bridge Node. I Set It Up Normally, Like it was shown in quick gateway guide. But, the problem seems to be, that tags position is very unstable. It seems like it is just giving random numbers for it’s x,y,z position. Tags are positioned in the corners of the room on 1.8m height. Can Someone Help?
Hi @xvichie
that can have multiple reasons.
-
If the TN is below anchors the the antenna should be faced down.
-
How well are Anchors position. The system can handle some smaller inaccuracy. However poorly aimed system will return poor distances.
-
Anchors should be at least 10cm from any wall.
Cheers
JK
I Tried All Of That. Now it seems like the y axis is malfunctioning. It’s Giving Ranges in 40cm.(Max. Y - Min.Y = 40cm). How Can I Fix That? NOTE: I have height Set on Z AXIS.
Hi @xvichie
is the area between AN and TN LOS or it is NLOS environment? You can get corrupted ranges when there are reflections.
Another idea is how do you power Anchors and TN?
Can you observe the output of LES command in shell - are distances between TN and AN stable or they vary?
Cheers
JK
It is LOS. There are bed, desk, and a piano(of course below the TNs) in the room. I power them Via USB Cable. And I Checked LES Command. It Seems Like It’s Unstable.
This Is From Tag #1:
dwm> les
dwm> D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.23 DA1F[-3.90,-2.00,1.80]=3.88 le_us=885 est[-0.68,0.32,1.39,86]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.25 DA1F[-3.90,-2.00,1.80]=3.95 le_us=885 est[-0.67,0.34,1.41,87]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=4.12 le_us=1068 est[-0.65,0.45,1.44,89]
D482[0.40,0.00,1.80]=1.03 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.86 le_us=885 est[-0.64,0.38,1.42,86]
D482[0.40,0.00,1.80]=1.07 D503[-3.95,0.00,1.80]=3.20 DA1F[-3.90,-2.00,1.80]=3.93 le_us=885 est[-0.65,0.39,1.49,86]
D482[0.40,0.00,1.80]=1.11 D503[-3.95,0.00,1.80]=3.24 DA1F[-3.90,-2.00,1.80]=3.79 le_us=885 est[-0.65,0.32,1.42,85]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.24 DA1F[-3.90,-2.00,1.80]=3.86 le_us=915 est[-0.65,0.29,1.40,86]
D482[0.40,0.00,1.80]=1.07 D503[-3.95,0.00,1.80]=3.24 DA1F[-3.90,-2.00,1.80]=3.83 le_us=885 est[-0.65,0.26,1.38,86]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.25 DA1F[-3.90,-2.00,1.80]=4.15 le_us=1281 est[-0.63,0.41,1.36,89]
D482[0.40,0.00,1.80]=1.09 D503[-3.95,0.00,1.80]=3.19 DA1F[-3.90,-2.00,1.80]=3.96 le_us=1068 est[-0.63,0.44,1.34,87]
D482[0.40,0.00,1.80]=1.04 D503[-3.95,0.00,1.80]=3.21 DA1F[-3.90,-2.00,1.80]=3.82 le_us=885 est[-0.64,0.38,1.37,88]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.21 DA1F[-3.90,-2.00,1.80]=3.76 le_us=885 est[-0.65,0.30,1.35,85]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.21 DA1F[-3.90,-2.00,1.80]=3.91 le_us=885 est[-0.65,0.32,1.40,86]
D482[0.40,0.00,1.80]=1.06 D503[-3.95,0.00,1.80]=3.19 DA1F[-3.90,-2.00,1.80]=3.92 le_us=823 est[-0.66,0.34,1.50,88]
D482[0.40,0.00,1.80]=1.09 D503[-3.95,0.00,1.80]=3.23 DA1F[-3.90,-2.00,1.80]=3.90 le_us=885 est[-0.66,0.33,1.47,86]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.90 le_us=885 est[-0.65,0.31,1.44,86]
D482[0.40,0.00,1.80]=1.02 D503[-3.95,0.00,1.80]=3.19 DA1F[-3.90,-2.00,1.80]=4.17 le_us=1678 est[-0.61,0.52,1.41,91]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.87 le_us=885 est[-0.62,0.44,1.40,86]
D482[0.40,0.00,1.80]=1.07 D503[-3.95,0.00,1.80]=3.21 DA1F[-3.90,-2.00,1.80]=4.27
D503[-3.95,0.00,1.80]=3.31 DA1F[-3.90,-2.00,1.80]=3.93 D482[0.40,0.00,1.80]=1.05 le_us=1007 est[-0.61,0.39,1.36,86]
D482[0.40,0.00,1.80]=1.10 D503[-3.95,0.00,1.80]=3.19 DA1F[-3.90,-2.00,1.80]=3.80 le_us=885 est[-0.63,0.33,1.36,85]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.86 le_us=885 est[-0.63,0.30,1.34,86]
D482[0.40,0.00,1.80]=1.02 D503[-3.95,0.00,1.80]=3.25 DA1F[-3.90,-2.00,1.80]=3.86 le_us=885 est[-0.63,0.27,1.35,86]
D482[0.40,0.00,1.80]=1.04 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.86 le_us=885 est[-0.63,0.25,1.35,86]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.20 DA1F[-3.90,-2.00,1.80]=4.19 le_us=1647 est[-0.59,0.48,1.34,91]
D482[0.40,0.00,1.80]=1.08 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=3.85 le_us=885 est[-0.60,0.40,1.32,86]
D482[0.40,0.00,1.80]=1.11 D503[-3.95,0.00,1.80]=3.22 DA1F[-3.90,-2.00,1.80]=3.87 le_us=885 est[-0.62,0.37,1.32,86]
D482[0.40,0.00,1.80]=1.05 D503[-3.95,0.00,1.80]=3.26 DA1F[-3.90,-2.00,1.80]=4.06 le_us=1098 est[-0.61,0.43,1.33,88]
This is From Tag #2:
D503[-3.95,0.00,1.80]=3.80 D482[0.40,0.00,1.80]=1.27 DA1F[-3.90,-2.00,1.80]=3.86 le_us=671 est[-0.36,-0.78,0.92,86]
D482[0.40,0.00,1.80]=1.55 D503[-3.95,0.00,1.80]=3.74 DA1F[-3.90,-2.00,1.80]=3.79 le_us=732 est[-0.38,-0.79,0.89,85]
D482[0.40,0.00,1.80]=1.27 D503[-3.95,0.00,1.80]=3.74 DA1F[-3.90,-2.00,1.80]=3.82 le_us=671 est[-0.37,-0.78,0.94,86]
D482[0.40,0.00,1.80]=1.56 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.39,-0.77,0.88,86]
D482[0.40,0.00,1.80]=1.36 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.87 le_us=671 est[-0.38,-0.75,0.89,86]
D482[0.40,0.00,1.80]=1.46 D503[-3.95,0.00,1.80]=3.77 DA1F[-3.90,-2.00,1.80]=3.75 le_us=640 est[-0.39,-0.80,0.92,85]
D482[0.40,0.00,1.80]=1.52 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.88 le_us=671 est[-0.39,-0.77,0.87,86]
D482[0.40,0.00,1.80]=1.60 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.80 le_us=640 est[-0.41,-0.78,0.83,85]
D482[0.40,0.00,1.80]=1.37 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.78 le_us=671 est[-0.40,-0.80,0.89,85]
D482[0.40,0.00,1.80]=1.27 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.38,-0.79,0.94,86]
D482[0.40,0.00,1.80]=1.47 D503[-3.95,0.00,1.80]=3.78 DA1F[-3.90,-2.00,1.80]=3.80 le_us=671 est[-0.38,-0.81,0.93,86]
D482[0.40,0.00,1.80]=1.39 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.91 le_us=671 est[-0.38,-0.76,0.91,86]
D482[0.40,0.00,1.80]=1.41 D503[-3.95,0.00,1.80]=3.74 DA1F[-3.90,-2.00,1.80]=3.84 le_us=671 est[-0.38,-0.75,0.90,86]
D482[0.40,0.00,1.80]=1.70 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.90 le_us=671 est[-0.41,-0.72,0.80,86]
D482[0.40,0.00,1.80]=1.23 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.87 le_us=671 est[-0.39,-0.72,0.87,86]
D482[0.40,0.00,1.80]=1.29 D503[-3.95,0.00,1.80]=3.82 DA1F[-3.90,-2.00,1.80]=3.89 le_us=671 est[-0.36,-0.73,0.91,86]
D482[0.40,0.00,1.80]=1.55 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.79 le_us=671 est[-0.38,-0.76,0.89,85]
D482[0.40,0.00,1.80]=1.41 D503[-3.95,0.00,1.80]=3.77 DA1F[-3.90,-2.00,1.80]=3.84 le_us=671 est[-0.38,-0.76,0.89,86]
D482[0.40,0.00,1.80]=1.45 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.38,-0.76,0.88,86]
D503[-3.95,0.00,1.80]=3.76 D482[0.40,0.00,1.80]=1.45 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.38,-0.75,0.87,86]
D482[0.40,0.00,1.80]=1.41 D503[-3.95,0.00,1.80]=3.74 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.39,-0.74,0.87,86]
D482[0.40,0.00,1.80]=1.41 D503[-3.95,0.00,1.80]=3.76
DA1F[-3.90,-2.00,1.80]=3.89 D482[0.40,0.00,1.80]=1.50 D503[-3.95,0.00,1.80]=3.75 le_us=732 est[-0.39,-0.72,0.83,86]
D482[0.40,0.00,1.80]=1.56 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.80 le_us=671 est[-0.40,-0.75,0.82,86]
D482[0.40,0.00,1.80]=1.48 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.80 le_us=671 est[-0.40,-0.77,0.83,86]
D482[0.40,0.00,1.80]=1.41 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.83 le_us=671 est[-0.40,-0.77,0.86,86]
D482[0.40,0.00,1.80]=1.23 D503[-3.95,0.00,1.80]=3.72 DA1F[-3.90,-2.00,1.80]=3.84 le_us=671 est[-0.39,-0.75,0.92,86]
D482[0.40,0.00,1.80]=1.47 D503[-3.95,0.00,1.80]=3.78 DA1F[-3.90,-2.00,1.80]=3.81 le_us=671 est[-0.39,-0.77,0.91,86]
D482[0.40,0.00,1.80]=1.72 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.85 le_us=640 est[-0.41,-0.76,0.82,86]
D482[0.40,0.00,1.80]=1.37 D503[-3.95,0.00,1.80]=3.78 DA1F[-3.90,-2.00,1.80]=3.75 le_us=671 est[-0.40,-0.81,0.91,85]
D482[0.40,0.00,1.80]=1.46 D503[-3.95,0.00,1.80]=3.78 DA1F[-3.90,-2.00,1.80]=3.85 le_us=671 est[-0.39,-0.80,0.89,86]
D482[0.40,0.00,1.80]=1.37 D503[-3.95,0.00,1.80]=3.75 DA1F[-3.90,-2.00,1.80]=3.86 le_us=671 est[-0.39,-0.78,0.90,86]
D482[0.40,0.00,1.80]=1.56 D503[-3.95,0.00,1.80]=3.73 DA1F[-3.90,-2.00,1.80]=3.87 le_us=671 est[-0.40,-0.74,0.84,86]
D482[0.40,0.00,1.80]=1.36 D503[-3.95,0.00,1.80]=3.76 DA1F[-3.90,-2.00,1.80]=3.83 le_us=671 est[-0.39,-0.75,0.88,86]
SECOND tag’s distance to D482 seems to be all over the place. And first Tag’s distance to DA1F seems to behave irregularly too. Keep in mind that I need to have somewhat accurate positions for both tags, as I Need to calculate Distance between them in any given moment.
NOTE: The Tags Were Static. Meaning That They Weren’t moving at All.
Hi @xvichie
I dont know your expectation but with PANS you would not get a better accuracy.
The observed “jumpy” it is not really all over the place - the measurement inaccuracy which can be caused by antenna radiation pattern - twist the TN a bit and you will se that you will get different position. Most of all we are no looking at ranges but at position and that is stable.
From the manual it is recommended to use 4 anchors to have a better system, with 3 anchors loosing range with one will lead to measurement failure.
If you are not happy with PANS you are free to develop your own solution 8-).
Cheers
JK
If you are not happy with PANS you are free to develop your own solution 8-).
Or buy one from someone else 
But realistically 5 cm horizontal noise and 10 cm vertical noise is reasonable for a UWB only system using the minimum number of anchors.
Given the antennas used you will also find that there is a distortion pattern, moving in a straight line won’t always give points in a straight line.
To get better you need either 1) more anchors to average over (and a system that makes use of them) 2) more time to average over (and slow moving objects) or 3) integrate with additional positioning sources like an IMU.
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