Incorrect Laser Values in Course Project Part 1 of Ros Basics in 5 days

I am trying to understand the range of values on the laser so I keep the robot in somewhere near the bottom left corner as in the picture


As per my understanding the values should increase from the right side of the laser to the left. However these are the values that I am getting.

(0.45766258239746094, 0.45737266540527344, 0.45988601446151733, 0.46240511536598206, 0.4634401202201843, 0.4568997323513031, 0.46293890476226807, 0.46756425499916077, 0.4444597661495209, 0.48161378502845764, 0.4772106111049652, 0.4718197286128998, 0.48638761043548584, 0.4934210479259491, 0.4968414306640625, 0.46711093187332153, 0.4895056486129761, 0.46977031230926514, 0.47030818462371826, 0.5004435181617737, 0.5017695426940918, 0.5134517550468445, 0.4952360689640045, 0.507992148399353, 0.49624744057655334, 0.5003706812858582, 0.508707582950592, 0.526946485042572, 0.5361310243606567, 0.5365089774131775, 0.5463898181915283, 0.5438351035118103, 0.538591742515564, 0.5415530204772949, 0.5361226797103882, 0.5163414478302002, 0.5282402038574219, 0.4889456331729889, 0.500724196434021, 0.4808792769908905, 0.477669894695282, 0.456587553024292, 0.4484412670135498, 0.4220806956291199, 0.4439069330692291, 0.42976874113082886, 0.4251199960708618, 0.4358591139316559, 0.4365881681442261, 0.4023384153842926, 0.397654265165329, 0.3956596553325653, 0.3481982946395874, 0.3707472085952759, 0.372199684381485, 0.3665905296802521, 0.35919418931007385, 0.37372490763664246, 0.3436022102832794, 0.37421149015426636, 0.3674962520599365, 0.3430381119251251, 0.35846954584121704, 0.3290184438228607, 0.3450523614883423, 0.3485022187232971, 0.33103400468826294, 0.3313524127006531, 0.3408564031124115, 0.333779513835907, 0.3496687710285187, 0.3225274980068207, 0.3063840866088867, 0.32180243730545044, 0.3160872459411621, 0.3220059871673584, 0.3263137936592102, 0.31409162282943726, 0.307158499956131, 0.2930839955806732, 0.3104185461997986, 0.2996295392513275, 0.3102899193763733, 0.30677399039268494, 0.3073360025882721, 0.29959097504615784, 0.3214713931083679, 0.3077608346939087, 0.30313536524772644, 0.30256372690200806, 0.31027352809906006, 0.3158954679965973, 0.31654030084609985, 0.31924566626548767, 0.31303131580352783, 0.3160797357559204, 0.3312133848667145, 0.30808889865875244, 0.3153231739997864, 0.3130093216896057, 0.30647701025009155, 0.32015979290008545, 0.3236110806465149, 0.3154882788658142, 0.3212578594684601, 0.32886040210723877, 0.33793526887893677, 0.33691418170928955, 0.3239344656467438, 0.3135828971862793, 0.3380480408668518, 0.33781111240386963, 0.3226586878299713, 0.33091408014297485, 0.3547520935535431, 0.3488277792930603, 0.36762773990631104, 0.3610915541648865, 0.34530994296073914, 0.34814417362213135, 0.35581696033477783, 0.37123534083366394, 0.3704216182231903, 0.3689110577106476, 0.3927314877510071, 0.3864608108997345, 0.3978842496871948, 0.3795384466648102, 0.393412709236145, 0.40892356634140015, 0.41913914680480957, 0.43529212474823, 0.4295932650566101, 0.4250591993331909, 0.4374566078186035, 0.45468151569366455, 0.46396201848983765,0.4624020755290985, 0.4604286253452301, 0.49997690320014954, 0.495614618062973, 0.506272554397583, 0.5176283717155457, 0.5324913263320923, 0.5627375245094299, 0.5595601201057434, 0.5763397812843323, 0.5948168635368347, 0.6299914121627808, 0.6467413306236267, 0.6618316769599915, 0.6844555139541626, 0.7080205678939819, 0.718226432800293, 0.7582366466522217, 0.7793160676956177, 0.8363256454467773, 0.8625485897064209, 0.9056888818740845, 0.9634799361228943, 1.003408432006836, 1.0709221363067627, 1.1155788898468018, 1.1882730722427368, 1.2732317447662354, 1.392918586730957, 1.3844350576400757, 1.3786979913711548, 1.39220130443573, 1.369314193725586, 1.3762893676757812, 1.3573565483093262, 1.372052550315857, 1.3765661716461182, 1.3759273290634155, 1.362156867980957, 1.3393895626068115, 1.3629735708236694, 1.362701416015625, 1.3648290634155273, 1.3462973833084106, 1.3576527833938599, 1.3706457614898682, 1.3594756126403809, 1.3615878820419312, 1.3514740467071533, 1.367093801498413, 1.3636329174041748, 1.3846544027328491, 1.3932069540023804, 1.3854085206985474, 1.3803703784942627, 1.4057737588882446, 1.4220356941223145, 1.4117244482040405, 1.407845139503479, 1.4102787971496582,1.4335929155349731, 1.4450122117996216, 1.4575308561325073, 1.4543554782867432, 1.4717905521392822, 1.497705101966858, 1.507440209388733, 1.503757119178772, 1.5418720245361328, 1.5454614162445068, 1.5614042282104492, 1.5625555515289307, 1.5898569822311401, 1.6196469068527222, 0.6604335308074951, 0.6709891557693481, 0.6834691166877747, 0.694719672203064, 0.6694955229759216, 0.6798296570777893,0.6920322775840759, 0.7024064660072327, 0.5807684659957886, 0.557281494140625, 0.56849205493927, 0.5494778752326965, 0.5788892507553101, 0.590097188949585, 0.590650737285614, 0.5754772424697876, 0.582115650177002, 0.5948261618614197, 0.6816440224647522, 0.6803863644599915, 0.6899181008338928, 0.6684351563453674, 0.6913170218467712, 0.6987415552139282, 0.7016839981079102, 2.066413640975952, 1.2004598379135132, 1.210057258605957, 1.2224310636520386, 1.2289526462554932, 1.9522117376327515, 1.9598298072814941, 1.936719298362732, 1.9303895235061646, 1.8848994970321655, 1.8750230073928833, 1.171779990196228, 1.091581106185913, 1.089590311050415, 1.1117311716079712, 1.1327764987945557, 1.8262914419174194, 1.7967654466629028, 1.7995978593826294, 1.7794805765151978, 1.802270531654358, 1.795499563217163, 1.771226406097412, 1.7764592170715332, 1.775747537612915, 1.7579175233840942, 1.7587125301361084, 1.7485605478286743, 1.7604200839996338, 1.7502481937408447, 1.761665940284729, 1.7684155702590942, 1.7536232471466064, 1.7547696828842163, 1.7495158910751343, 1.7602691650390625, 1.7697571516036987, 1.7753723859786987, 1.7555227279663086, 1.7747018337249756, 1.774643898010254, 1.7754039764404297, 1.7843694686889648, 1.801511526107788, 1.7908378839492798, 1.8049272298812866, 1.7915959358215332, 1.719283103942871, 1.6171444654464722, 1.5467288494110107, 1.4561443328857422, 1.3711447715759277, 1.319226622581482, 0.7574495077133179, 0.7367842197418213, 0.741550862789154, 0.7240128517150879, 0.7157444357872009, 0.7099963426589966, 0.9905376434326172, 0.9525344967842102, 0.9335363507270813, 0.9031702280044556, 0.8853455185890198, 0.8458364009857178, 0.8648041486740112, 0.8149782419204712, 0.7959050536155701, 0.7561257481575012, 0.7612028121948242, 0.7370176911354065, 0.7423316836357117, 0.7081595659255981, 0.7112141847610474, 0.6910663843154907, 0.6562374830245972, 0.6585683226585388, 0.6301109790802002, 0.6371744275093079, 0.6135005950927734, 0.6093813180923462, 0.600428581237793, 0.5911675691604614, 0.5902130603790283, 0.5785397291183472, 0.5605062246322632, 0.5670309066772461, 0.5344839692115784, 0.5426127314567566, 0.5491223931312561, 0.532565176486969, 0.5265817046165466, 0.5237036943435669, 0.5174288749694824, 0.5184686779975891, 0.5064498782157898, 0.5010533928871155, 0.5197751522064209, 0.511588990688324, 0.5050473809242249, 0.4898233115673065, 0.4845542907714844, 0.5146804451942444, 0.49350792169570923, 0.4561493396759033, 0.4766533076763153, 0.46648770570755005, 0.4799822270870209, 0.4529428482055664, 0.46792271733283997, 0.45038124918937683, 0.4704132676124573, 0.4806531071662903, 0.47076258063316345, 0.4842279553413391, 0.46872690320014954, 0.4505198299884796, 0.45437169075012207, 0.4668974280357361, 0.4678471088409424, 0.49215447902679443, 0.4635048806667328, 0.44805091619491577, 0.4577829837799072)

The values for right and left rays are similar even if the right side is much more close to the wall than the left size is.
Am I doing something wrong?
The code for now is simply a subscriber to ‘/scan’ topic that prints the ranges

Hi, welcome to the community!

No, you are not doing anything wrong. Like you said, the scan values are “reversed.” The reason for this is because of the setup of the actual robot, where the hardware has to be the way it is. If you look at the frame of the scan element (you can use RViZ for this) you’ll see that the scan frame has a 180 degree offset.

You’ll have to keep this in mind as you create your program.

Thanks! I did the exercise with the info you provided. The RViZ tip was especially useful.

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