[Solved] Please explain warnings

I know where these are originating but do not know why. Can anyone explain what these warnings really mean. I have included enough to show progress. This was actually a successful run of tutorial_9 but would like to determine how to tun out these warnings.

[ INFO] [1559571289.645160466]: Scan time: 1559571291,454989664
[ WARN] [1559571289.645281941]: Transform lookup failed, drop this scan
[ INFO] [1559571290.004241972]: Scan time: 1559571291,488326780
[ WARN] [1559571290.004516199]: Transform lookup failed, drop this scan
[ INFO] [1559571290.023417804]: Scan time: 1559571291,555014126
LookupTime: 1559571291, 555014126
[ INFO] [1559571290.418736208]: Scan time: 1559571292,221722595
[ WARN] [1559571290.418922502]: Transform lookup failed, drop this scan
[ INFO] [1559571290.459511693]: Scan time: 1559571292,255051367
[ WARN] [1559571290.459685727]: Transform lookup failed, drop this scan
[ INFO] [1559571290.499077653]: Scan time: 1559571292,321676962
[ WARN] [1559571290.499398590]: Transform lookup failed, drop this scan
[ INFO] [1559571290.520160090]: Scan time: 1559571292,355014078
[ WARN] [1559571290.520308192]: Transform lookup failed, drop this scan
[ INFO] [1559571290.539787452]: Scan time: 1559571292,421712152
LookupTime: 1559571292, 421712152
[ INFO] [1559571290.936886738]: Scan time: 1559571292,755064003
[ WARN] [1559571290.937056760]: Transform lookup failed, drop this scan
[ INFO] [1559571290.958405677]: Scan time: 1559571292,788402073
[ WARN] [1559571290.958563861]: Transform lookup failed, drop this scan
[ INFO] [1559571290.977222315]: Scan time: 1559571292,821662180
[ WARN] [1559571290.977491300]: Transform lookup failed, drop this scan
[ INFO] [1559571290.998673626]: Scan time: 1559571292,854714624
[ WARN] [1559571290.998916357]: Transform lookup failed, drop this scan
[ INFO] [1559571291.038689559]: Scan time: 1559571292,888005249
LookupTime: 1559571292, 888005249
[ INFO] [1559571291.474894374]: Scan time: 1559571293,221191875
LookupTime: 1559571293, 221191875
[ INFO] [1559571291.871352596]: Scan time: 1559571293,754332296
LookupTime: 1559571293, 754332296
[ INFO] [1559571292.266028051]: Scan time: 1559571294,120814316
[ WARN] [1559571292.266555191]: Transform lookup failed, drop this scan
[ INFO] [1559571292.287118040]: Scan time: 1559571294,154111378
[ WARN] [1559571292.287420950]: Transform lookup failed, drop this scan
[ INFO] [1559571292.326333650]: Scan time: 1559571294,187449209
[ WARN] [1559571292.326593618]: Transform lookup failed, drop this scan
[ INFO] [1559571292.346432835]: Scan time: 1559571294,220786325
[ WARN] [1559571292.346611742]: Transform lookup failed, drop this scan
[ INFO] [1559571292.367231986]: Scan time: 1559571294,254124395
[ WARN] [1559571292.367482797]: Transform lookup failed, drop this scan
[ INFO] [1559571292.426300255]: Scan time: 1559571294,287492268
LookupTime: 1559571294, 287492268
[ INFO] [1559571292.821132283]: Scan time: 1559571294,654350988
[ WARN] [1559571292.821301379]: Transform lookup failed, drop this scan
[ INFO] [1559571292.841488962]: Scan time: 1559571294,721025936
[ WARN] [1559571292.841620348]: Transform lookup failed, drop this scan
[ INFO] [1559571292.921733859]: Scan time: 1559571294,754217379
[ WARN] [1559571292.921870633]: Transform lookup failed, drop this scan
[ INFO] [1559571292.982611448]: Scan time: 1559571294,787496798
[ WARN] [1559571292.982723055]: Transform lookup failed, drop this scan
[ INFO] [1559571293.042052830]: Scan time: 1559571294,820798389
[ WARN] [1559571293.042167243]: Transform lookup failed, drop this scan
[ INFO] [1559571293.161183444]: Scan time: 1559571294,854074471
LookupTime: 1559571294, 854074471
[ INFO] [1559571293.553007821]: Scan time: 1559571295,420428984
[ WARN] [1559571293.553260292]: Transform lookup failed, drop this scan
[ INFO] [1559571293.573664845]: Scan time: 1559571295,453698866
[ WARN] [1559571293.573871668]: Transform lookup failed, drop this scan
[ INFO] [1559571298.179038441]: Scan time: 1559571300,33268682
[ WARN] [1559571298.179299765]: Transform lookup failed, drop this scan
[ INFO] [1559571298.199837614]: Scan time: 1559571300,67011826
LookupTime: 1559571300, 67011826
[ INFO] [1559571298.576092800]: Scan time: 1559571300,510124676
[ WARN] [1559571298.576335411]: Transform lookup failed, drop this scan
[ INFO] [1559571298.616142603]: Scan time: 1559571300,544524424
[ WARN] [1559571298.616311964]: Transform lookup failed, drop this scan
[ INFO] [1559571298.658166913]: Scan time: 1559571300,578104727
[ WARN] [1559571298.658395814]: Transform lookup failed, drop this scan
[ INFO] [1559571298.676876798]: Scan time: 1559571300,611454479
[ WARN] [1559571298.677073608]: Transform lookup failed, drop this scan
[ INFO] [1559571298.737349240]: Scan time: 1559571300,645736448
LookupTime: 1559571300, 645736448
[ INFO] [1559571299.147750535]: Scan time: 1559571301,86069099
[ WARN] [1559571299.147848741]: Transform lookup failed, drop this scan
[ INFO] [1559571299.268745715]: Scan time: 1559571301,121026985
[ WARN] [1559571299.268922103]: Transform lookup failed, drop this scan
[ INFO] [1559571299.287934230]: Scan time: 1559571301,188476793
LookupTime: 1559571301, 188476793
[ INFO] [1559571299.698493235]: Scan time: 1559571301,699010126
[ WARN] [1559571299.698582197]: Transform lookup failed, drop this scan
[ INFO] [1559571304.555481954]: Scan time: 1559571306,697982065
LookupTime: 1559571306, 697982065
[ INFO] [1559571304.932442617]: Scan time: 1559571307,67228071
[ WARN] [1559571304.932624639]: Transform lookup failed, drop this scan
[ INFO] [1559571304.953209725]: Scan time: 1559571307,101184599
[ WARN] [1559571304.953407572]: Transform lookup failed, drop this scan
[ INFO] [1559571305.052850749]: Scan time: 1559571307,134522669
[ WARN] [1559571305.052965592]: Transform lookup failed, drop this scan
[ INFO] [1559571305.133008595]: Scan time: 1559571307,169104092
[ WARN] [1559571305.133266828]: Transform lookup failed, drop this scan
[ INFO] [1559571305.193224097]: Scan time: 1559571307,202889196
[ WARN] [1559571305.193377539]: Transform lookup failed, drop this scan
[ INFO] [1559571305.232555192]: Scan time: 1559571307,236681215
[ WARN] [1559571305.232749958]: Transform lookup failed, drop this scan
[ INFO] [1559571305.273075321]: Scan time: 1559571307,270312778
LookupTime: 1559571307, 270312778
[ INFO] [1559571305.673669770]: Scan time: 1559571307,607628576
[ WARN] [1559571305.673837309]: Transform lookup failed, drop this scan
[ INFO] [1559571305.713524118]: Scan time: 1559571307,640965693
[ WARN] [1559571305.713594555]: Transform lookup failed, drop this scan
[ INFO] [1559571305.733631213]: Scan time: 1559571307,674542896
[ WARN] [1559571305.733738341]: Transform lookup failed, drop this scan
[ INFO] [1559571305.774168476]: Scan time: 1559571307,708347551
[ WARN] [1559571305.774252540]: Transform lookup failed, drop this scan
[ INFO] [1559571305.814220674]: Scan time: 1559571307,775143377
[ WARN] [1559571305.814335751]: Transform lookup failed, drop this scan
[ INFO] [1559571305.833778214]: Scan time: 1559571307,808837406
LookupTime: 1559571307, 808837406
[ INFO] [1559571306.211490722]: Scan time: 1559571308,179654352
[ WARN] [1559571306.211582322]: Transform lookup failed, drop this scan
[ INFO] [1559571306.312045366]: Scan time: 1559571308,213082306
[ WARN] [1559571306.312165923]: Transform lookup failed, drop this scan
[ INFO] [1559571306.333809094]: Scan time: 1559571308,279757254
[ WARN] [1559571306.333903087]: Transform lookup failed, drop this scan
[ INFO] [1559571306.351634514]: Scan time: 1559571308,313094370
[ WARN] [1559571306.351729106]: Transform lookup failed, drop this scan
[ INFO] [1559571306.411831076]: Scan time: 1559571308,346432201
LookupTime: 1559571308, 346432201
[ INFO] [1559571306.803730816]: Scan time: 1559571308,814113132
LookupTime: 1559571308, 814113132
[ INFO] [1559571307.203635155]: Scan time: 1559571309,217186682
[ WARN] [1559571307.203704533]: Transform lookup failed, drop this scan
[ INFO] [1559571307.223939864]: Scan time: 1559571309,250854723
[ WARN] [1559571307.224022991]: Transform lookup failed, drop this scan
[ INFO] [1559571307.244029001]: Scan time: 1559571309,284367554
[ WARN] [1559571307.244182735]: Transform lookup failed, drop this scan
[ INFO] [1559571307.263702542]: Scan time: 1559571309,318450682
[ WARN] [1559571307.263843641]: Transform lookup failed, drop this scan
[ INFO] [1559571307.304530358]: Scan time: 1559571309,352035753
[ WARN] [1559571307.304639045]: Transform lookup failed, drop this scan
[ INFO] [1559571307.344280885]: Scan time: 1559571309,385638229
LookupTime: 1559571309, 385638229
[ INFO] [1559571307.731582938]: Scan time: 1559571309,787587873
[ WARN] [1559571307.731881416]: Transform lookup failed, drop this scan
[ INFO] [1559571307.751991069]: Scan time: 1559571309,821429722
[ WARN] [1559571307.752069444]: Transform lookup failed, drop this scan
[ INFO] [1559571307.793016290]: Scan time: 1559571309,854891531
[ WARN] [1559571307.793156283]: Transform lookup failed, drop this scan
[ INFO] [1559571307.832039364]: Scan time: 1559571309,888348572
[ WARN] [1559571307.832136125]: Transform lookup failed, drop this scan
[ INFO] [1559571307.871667707]: Scan time: 1559571309,921685450
[ WARN] [1559571307.871820577]: Transform lookup failed, drop this scan
[ INFO] [1559571307.892097691]: Scan time: 1559571309,955270998
LookupTime: 1559571309, 955270998
[ INFO] [1559571308.282408613]: Scan time: 1559571310,290625803
[ WARN] [1559571308.282559555]: Transform lookup failed, drop this scan
[ INFO] [1559571308.303072830]: Scan time: 1559571310,324043743
[ WARN] [1559571308.303152495]: Transform lookup failed, drop this scan
[ INFO] [1559571308.323055352]: Scan time: 1559571310,357455246
[ WARN] [1559571308.323153400]: Transform lookup failed, drop this scan
[ INFO] [1559571308.362491332]: Scan time: 1559571310,424590103
[ WARN] [1559571308.362599043]: Transform lookup failed, drop this scan
[ INFO] [1559571308.423057000]: Scan time: 1559571310,458114378
[ WARN] [1559571308.423144129]: Transform lookup failed, drop this scan
[ INFO] [1559571308.462765758]: Scan time: 1559571310,491682522
LookupTime: 1559571310, 491682522
[ INFO] [1559571308.888764175]: Scan time: 1559571310,894184343
[ WARN] [1559571308.888837420]: Transform lookup failed, drop this scan
[ INFO] [1559571308.909043245]: Scan time: 1559571310,961390011
[ WARN] [1559571308.909143516]: Transform lookup failed, drop this scan
[ INFO] [1559571309.009689410]: Scan time: 1559571310,995073549
LookupTime: 1559571310, 995073549
[ INFO] [1559571309.452257356]: Scan time: 1559571311,497271530
[ WARN] [1559571309.452417816]: Transform lookup failed, drop this scan
[ INFO] [1559571309.512576557]: Scan time: 1559571311,531294100
LookupTime: 1559571311, 531294100
[ INFO] [1559571309.942629197]: Scan time: 1559571312,33102266
LookupTime: 1559571312, 33102266
[ INFO] [1559571315.461630753]: Scan time: 1559571317,388509981
[ WARN] [1559571315.461731293]: Transform lookup failed, drop this scan
[ INFO] [1559571315.482280580]: Scan time: 1559571317,421735994
LookupTime: 1559571317, 421735994
[ INFO] [1559571315.860045605]: Scan time: 1559571317,890173666
[ WARN] [1559571315.860186463]: Transform lookup failed, drop this scan
[ INFO] [1559571315.920970621]: Scan time: 1559571318,24116032
LookupTime: 1559571318, 24116032
[ INFO] [1559571316.298659396]: Scan time: 1559571318,292037003
[ WARN] [1559571316.298781796]: Transform lookup failed, drop this scan
[ INFO] [1559571316.318911015]: Scan time: 1559571318,325720779
[ WARN] [1559571316.319007559]: Transform lookup failed, drop this scan
[ INFO] [1559571316.338779409]: Scan time: 1559571318,392939560
[ WARN] [1559571316.338903445]: Transform lookup failed, drop this scan
[ INFO] [1559571316.378751557]: Scan time: 1559571318,426906578
[ WARN] [1559571316.378891394]: Transform lookup failed, drop this scan
[ INFO] [1559571316.478805374]: Scan time: 1559571318,468445293
LookupTime: 1559571318, 468445293
[ INFO] [1559571316.844919184]: Scan time: 1559571318,635132305
LookupTime: 1559571318, 635132305
[ INFO] [1559571317.224838051]: Scan time: 1559571319,191857569
LookupTime: 1559571319, 191857569
[ INFO] [1559571317.590748366]: Scan time: 1559571319,726161949
[ WARN] [1559571317.590873365]: Transform lookup failed, drop this scan
[ INFO] [1559571317.611263668]: Scan time: 1559571319,792885296
[ WARN] [1559571317.611453211]: Transform lookup failed, drop this scan
[ INFO] [1559571317.630860506]: Scan time: 1559571319,826223604
[ WARN] [1559571317.631040812]: Transform lookup failed, drop this scan
[ INFO] [1559571317.712433723]: Scan time: 1559571319,893082611
[ WARN] [1559571317.712560847]: Transform lookup failed, drop this scan
[ INFO] [1559571317.731543939]: Scan time: 1559571319,926420443
[ WARN] [1559571317.731757917]: Transform lookup failed, drop this scan
[ INFO] [1559571317.771198294]: Scan time: 1559571319,959813587
[ WARN] [1559571317.771428384]: Transform lookup failed, drop this scan
[ INFO] [1559571317.811160874]: Scan time: 1559571319,993186466
[ WARN] [1559571317.811256916]: Transform lookup failed, drop this scan
[ INFO] [1559571318.131329185]: Scan time: 1559571320,127563946
[ WARN] [1559571318.131412304]: Transform lookup failed, drop this scan
[ INFO] [1559571318.170902174]: Scan time: 1559571320,229568712
[ WARN] [1559571318.170987458]: Transform lookup failed, drop this scan
[ INFO] [1559571318.191588561]: Scan time: 1559571320,263535969
[ WARN] [1559571318.191701239]: Transform lookup failed, drop this scan
[ INFO] [1559571318.231561010]: Scan time: 1559571320,296243660
[ WARN] [1559571318.231659283]: Transform lookup failed, drop this scan
[ INFO] [1559571318.251719993]: Scan time: 1559571320,329581730
[ WARN] [1559571318.251849460]: Transform lookup failed, drop this scan
[ INFO] [1559571318.270857814]: Scan time: 1559571320,396051399
[ WARN] [1559571318.271024112]: Transform lookup failed, drop this scan
[ INFO] [1559571318.291603048]: Scan time: 1559571320,429350607
[ WARN] [1559571318.291718760]: Transform lookup failed, drop this scan
[ INFO] [1559571318.352978236]: Scan time: 1559571320,461379997
[ WARN] [1559571318.353078441]: Transform lookup failed, drop this scan
[ INFO] [1559571318.370959354]: Scan time: 1559571320,494621508
[ WARN] [1559571318.371104715]: Transform lookup failed, drop this scan
[ INFO] [1559571318.410779355]: Scan time: 1559571320,527959339
[ WARN] [1559571318.410921173]: Transform lookup failed, drop this scan
[ INFO] [1559571318.470756807]: Scan time: 1559571320,561392061
LookupTime: 1559571320, 561392061
[ INFO] [1559571318.856693567]: Scan time: 1559571320,928791277
[ WARN] [1559571318.856780986]: Transform lookup failed, drop this scan
[ INFO] [1559571318.877303939]: Scan time: 1559571320,962324135
[ WARN] [1559571318.877501156]: Transform lookup failed, drop this scan
[ INFO] [1559571318.897321731]: Scan time: 1559571320,995662205
[ WARN] [1559571318.897482093]: Transform lookup failed, drop this scan
[ INFO] [1559571318.916958376]: Scan time: 1559571321,29084436
[ WARN] [1559571318.917061206]: Transform lookup failed, drop this scan
[ INFO] [1559571318.956980022]: Scan time: 1559571321,62710516
LookupTime: 1559571321, 62710516
[ INFO] [1559571319.340922743]: Scan time: 1559571321,431502096
[ WARN] [1559571319.340999927]: Transform lookup failed, drop this scan
[ INFO] [1559571319.361776725]: Scan time: 1559571321,464839928
[ WARN] [1559571319.361897611]: Transform lookup failed, drop this scan
[ INFO] [1559571319.421789689]: Scan time: 1559571321,498947613
[ WARN] [1559571319.422322933]: Transform lookup failed, drop this scan
[ INFO] [1559571319.461507503]: Scan time: 1559571321,532998554
[ WARN] [1559571319.463347532]: Transform lookup failed, drop this scan
[ INFO] [1559571319.502197653]: Scan time: 1559571321,566335432
[ WARN] [1559571319.502330064]: Transform lookup failed, drop this scan
[ INFO] [1559571319.541356576]: Scan time: 1559571321,599685184
LookupTime: 1559571321, 599685184
[ INFO] [1559571319.947241077]: Scan time: 1559571322,7399075
[ WARN] [1559571319.947362265]: Transform lookup failed, drop this scan
[ INFO] [1559571324.790696844]: Scan time: 1559571326,871615641
LookupTime: 1559571326, 871615641
[ INFO] [1559571325.190594584]: Scan time: 1559571327,73166840
LookupTime: 1559571327, 73166840
[ INFO] [1559571325.587814827]: Scan time: 1559571327,675699942
[ WARN] [1559571325.587950982]: Transform lookup failed, drop this scan
[ INFO] [1559571325.609147191]: Scan time: 1559571327,708102219
[ WARN] [1559571325.609325286]: Transform lookup failed, drop this scan
[ INFO] [1559571325.708046983]: Scan time: 1559571327,741256468
[ WARN] [1559571325.708157099]: Transform lookup failed, drop this scan
[ INFO] [1559571325.728185670]: Scan time: 1559571327,774593584
[ WARN] [1559571325.728302743]: Transform lookup failed, drop this scan
[ INFO] [1559571325.768132734]: Scan time: 1559571327,807931416
[ WARN] [1559571325.768234466]: Transform lookup failed, drop this scan
[ INFO] [1559571325.808179371]: Scan time: 1559571327,841268532
[ WARN] [1559571325.808307946]: Transform lookup failed, drop this scan
[ INFO] [1559571325.908399647]: Scan time: 1559571327,974802248
LookupTime: 1559571327, 974802248
[ INFO] [1559571326.298789117]: Scan time: 1559571328,408586971
[ WARN] [1559571326.298944949]: Transform lookup failed, drop this scan
[ INFO] [1559571326.339517904]: Scan time: 1559571328,441023104
[ WARN] [1559571326.339788759]: Transform lookup failed, drop this scan
[ INFO] [1559571326.380055205]: Scan time: 1559571328,473315470
LookupTime: 1559571328, 473315470
[ INFO] [1559571326.784267300]: Scan time: 1559571328,907176725
[ WARN] [1559571326.784386092]: Transform lookup failed, drop this scan
[ INFO] [1559571326.824572948]: Scan time: 1559571328,940547935
[ WARN] [1559571326.824700004]: Transform lookup failed, drop this scan
[ INFO] [1559571326.864523187]: Scan time: 1559571328,974179260
[ WARN] [1559571326.864630746]: Transform lookup failed, drop this scan
[ INFO] [1559571326.904555065]: Scan time: 1559571329,7568590
[ WARN] [1559571326.904674544]: Transform lookup failed, drop this scan
[ INFO] [1559571326.925132912]: Scan time: 1559571329,42500488
LookupTime: 1559571329, 42500488
[ INFO] [1559571327.347855789]: Scan time: 1559571329,476539604
[ WARN] [1559571327.347979739]: Transform lookup failed, drop this scan
[ INFO] [1559571327.408170573]: Scan time: 1559571329,543212406
[ WARN] [1559571327.408267006]: Transform lookup failed, drop this scan
[ INFO] [1559571327.448196888]: Scan time: 1559571329,576139204
[ WARN] [1559571327.448307671]: Transform lookup failed, drop this scan
[ INFO] [1559571327.489305685]: Scan time: 1559571329,609477274
LookupTime: 1559571329, 609477274
[ INFO] [1559571327.916007475]: Scan time: 1559571330,41372292
[ WARN] [1559571327.916208975]: Transform lookup failed, drop this scan
[ INFO] [1559571327.958858516]: Scan time: 1559571330,74759237
[ WARN] [1559571327.958966772]: Transform lookup failed, drop this scan
[ INFO] [1559571327.996225494]: Scan time: 1559571330,141434185
[ WARN] [1559571327.996335891]: Transform lookup failed, drop this scan
[ INFO] [1559571328.056364695]: Scan time: 1559571330,174809448
LookupTime: 1559571330, 174809448
[ INFO] [1559571328.455605768]: Scan time: 1559571330,575135462
[ WARN] [1559571328.455683381]: Transform lookup failed, drop this scan
[ INFO] [1559571328.475733107]: Scan time: 1559571330,608543388
[ WARN] [1559571328.475814978]: Transform lookup failed, drop this scan
[ INFO] [1559571328.515970202]: Scan time: 1559571330,641810410
[ WARN] [1559571328.516049217]: Transform lookup failed, drop this scan
[ INFO] [1559571328.536500355]: Scan time: 1559571330,675044767
[ WARN] [1559571328.536576746]: Transform lookup failed, drop this scan
[ INFO] [1559571328.576615441]: Scan time: 1559571330,708381645
LookupTime: 1559571330, 708381645
[ INFO] [1559571328.972013900]: Scan time: 1559571331,108371012
[ WARN] [1559571328.972140007]: Transform lookup failed, drop this scan
[ INFO] [1559571334.066942023]: Scan time: 1559571336,203319780
[ WARN] [1559571334.067056818]: Transform lookup failed, drop this scan
[ INFO] [1559571334.227327233]: Scan time: 1559571336,269941084
[ WARN] [1559571334.227406107]: Transform lookup failed, drop this scan
[ INFO] [1559571334.267377170]: Scan time: 1559571336,303278200
LookupTime: 1559571336, 303278200
[ INFO] [1559571334.688888595]: Scan time: 1559571336,803773634
[ WARN] [1559571334.689033380]: Transform lookup failed, drop this scan
[ INFO] [1559571334.689113829]: Object detected
[ INFO] [1559571334.709245386]: Object detected during exploration, stop exploration task
[search_manager-7] process has finished cleanly
log file: /home/husarion/.ros/log/770347c8-8609-11e9-aaa8-80c5f2fe5529/search_manager-7*.log

Hello garrisdw,

The error is caused while checking for transform between /map and /camera_link frames. It it happen to publish scan earlier than appropriate tf, then warning will be thrown.

To prevent it, add waitForTransform before obtaining the transform:

listener->waitForTransform("/map", "/camera_link", scan_time, ros::Duration(1.0));
listener->lookupTransform("/map", "/camera_link", scan_time, rgbd_scan_to_map_transform);

With above modification, node will wait 1 second for frame to be published.

Regards,
Ɓukasz

Thank you for the quick response! I will add that today and retest.