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Did you consider implementing a GPS like protocol for the DWM1000?

This requires:

• Synchronizing the timestamps of all devices;
• Each anchor send its position and current timestamp;
• From the positions and timestamps received, the devices compute their position.

Pros:

• Works with any number of tags are they are in "listening only" mode;
• Adding an anchor do not require to change the configuration of each tag;
• The tags are "stupid" and thus do not need more configuration than the band, power, ... and can join any network seamlessly.

Cons:

• The timestamp synchronization must be precise;
• The anchors must send their messages in a synchronous way.

https://github.com/lab11/polypoint/blob/master/contiki/apps/pp_oneway_tag/pp_oneway_tag.c#L191

This picks the 10th percentile of 27 measurements unconditionally. It should instead find the 10th percentile of the number of valid measurements.

Analysis in MATLAB recreating the algorithms used on the TriPoint tags indicates range error should follow an approximate gaussian distribution with little variance. Resulting range estimates from TriPoint follow a bimodal distribution with +/- 0.5 meters between peaks

Should consolidate all app-specific static variables in a common scratchspace

The change to the UUID made in fc9f888:
https://github.com/lab11/polypoint/blob/master/nrf51822/apps/tritag/main.c#L54

doesn't agree with:
https://github.com/lab11/polypoint/blob/master/phone/tritag.js#L5
or
https://github.com/lab11/polypoint/blob/master/phone/tritag-summon/js/index.js#L6

Specifically, I think the 3rd and 4th-to-last bytes in the array (0x31, 0x52) are flipped?

@brghena is this a typo or am I misunderstanding something here?

If power is removed and re-applied within a period of 60 seconds, the TriPoint module will become unresponsive due to the Decawave chip not responding to any commands. This may be un-fixable with the current Decawave silicon.

1. call PWR_EnterSTOPMode() instead
2. Fix main loop so interrupts can't occur before WFI
3. Look at stm-sleep branch for how to get the I2C to wake the STM
4. Figure out why just changing the sleep function doesn't work.

This used to live on nuclear, but nuclear is no more:

$ cat publish.sh
#!/usr/bin/env bash

scp -r cordova.js cordova_plugins.js css img index.html js plugins nuclear.eecs.umich.edu:/opt/public/ble/tritag/

@bradjc @brghena @tzachari this may be a more general problem for summon apps, or is this solved already and I just need to push this app somewhere else?

hi , ploypoint supports for multiple tags?

• Patch wire from USB+ to BAT+ skips over LTC4065. Should either replace LTC with something else to serve the original purpose, or determine it really wasn't needed and remove it.

Hello,

I've made a few prototypes to test out TriPoint circuits on TriBase and TriTag boards. The PCB's arrived mounted well and I'm able to program nRF51 and STM but afterwards it seems that there's an issue with getting the whole device to work... The only thing I can do is connect via BLE (so nRF51 works ok) but STM + DW1000 seem to not be doing anything...

Do you maybe have any tips on what to check? I'm attaching the activity on I2C and SPI lines from the device startup - as you see the I2C commands don't seem right but the FW tested is

Tried with tridev and check_version.py scripts but it also fails even though the device enumerates correctly in dmesg.

Traceback (most recent call last):
  File "check_version.py", line 8, in <module>
    tp = tripoint.TriPoint()
  File "/../lab11-polypoint/tripoint/tripoint.py", line 28, in __init__
    self.tripoint = mpsse.MPSSE(mpsse.I2C, mpsse.FOUR_HUNDRED_KHZ)
  File "/usr/local/lib/python2.7/dist-packages/mpsse.py", line 70, in __init__
    raise Exception, self.ErrorString()
Exception: device not found

Now that the final round uses the 'best' antenna at each anchor, the clock offset calculation needs to be updated to select the ToA which corresponds to the correct tag antenna/anchor antenna pairing.