Hi, Glad to hear your making progress. The -1 ranging values are actually an error flag which means the node is getting the radio trigger, but not properly able to distinguish the start of the pulse - usually if the background noise is too high or pulse amplitude too low (i.e. nodes too far away). See the getRange function in OutsideRangingSensorM.nc for the error conditions.
If you are getting other positive numbers , then that is a good sign. I've found that the range estimates are generally about 40cm too low. I've also found that the range estimates can vary significantly based upon which sensor board is sounding. I think this may be due to manufacturing inconsistencies in the sounder manufacturing. A useful exercise is to plot the range estimates from the nodes as a function of true separation. Doing this I found that the results generally had good linearity, but quite large offsets from the true value (generally 40cm). Other things to note is that the environment can affect the readings - echoes and background noise should be minimised. The effective separation for ranging is roughly 50-200cm. I'd definitely be interested to see any of your findings and compare them with my own. Mike -----Original Message----- From: Sarfraz Nawaz [mailto:[EMAIL PROTECTED] Sent: 22 September 2006 05:56 To: Michael Collett Cc: [EMAIL PROTECTED]; TinyOS Help Subject: RE: Vanderbilt Acoustic Ranging on MicaZ Hi Michael, Thanks for your helpful directions. I had followed your approach regarding Clock and TimerJiffyAsync and was able to compile the TestAcousticRanging appliation. However, when running I was always getting "-1" as the distance between two motes. On further inspection I realized that I had forgotten to put PLATFORM_MICAZ in certain components. I have inserted PLATFORM_MICA2 || PLATFORM_MICAZ in OutsideRangingSensorM.nc and HPLADCC.nc and now I am getting non negative numbers as distances though I have yet to verify if the distance measurements are indeed correct. Did you manage to check if the distance measurements are working properly? > > Hi, > > Yes I've managed to get it to work (although I think it may still be a bit > buggy). The main problem is keeping track of the use of the clock.nc > interfaces and headers. The versions from Vanderbilt share the same names, > but differ in functionality from the standard tos libraries. > > The errors that occur are mostly redefinitions of enums. In the clock.h > file from the VU package, I just renamed the enums to: > > enum > { > TOSv_I1000PS = 32, TOSv_S1000PS = 1, > TOSv_I100PS = 41, TOSv_S100PS = 2, > TOSv_I10PS = 102, TOSv_S10PS = 3, > TOSv_I4096PS = 7, TOSv_S4096PS = 1, > TOSv_I2048PS = 15, TOSv_S2048PS = 1, > TOSv_I1024PS = 31, TOSv_S1024PS = 1, > TOSv_I512PS = 63, TOSv_S512PS = 1, > TOSv_I256PS = 127, TOSv_S256PS = 1, > TOSv_I128PS = 255, TOSv_S128PS = 1, > TOSv_I64PS = 64, TOSv_S64PS = 2, > TOSv_I32PS = 128, TOSv_S32PS = 2, > TOSv_I16PS = 64, TOSv_S16PS = 3, > TOSv_I8PS = 128, TOSv_S8PS = 3, > TOSv_I4PS = 128, TOSv_S4PS = 4, > TOSv_I2PS = 128, TOSv_S2PS = 5, > TOSv_I1PS = 128, TOSv_S1PS = 6, > TOSv_I0PS = 0, TOSv_S0PS = 0, > }; > > Looking at the standard version of clock.h the assigned values are the > same any way, so you may even be able to get away with chopping out all > the variables which are redefined (as they are correctly defined > elsewhere). > > Also make sure you have replaced: > > #elif defined(PLATFORM_MICA2) || defined(PLATFORM_MICA2DOT) > > With something like > > #elif defined(PLATFORM_MICA2) || defined(PLATFORM_MICAZ) > > wherever it occurs (you will have to trawl through the files, but > undefined errors should also point you in the right direction). > > I made a small change to TimerJiffyAsync, so it uses Clock2.nc interface > (a copy of clock.nc, but kept separate). > > This should get you started in the right direction. It's a lot easier than > writing your own new timer (which I originally tried, with little > success). > > Keep me posted with your progress and good luck. > > Mike > > -----Original Message----- > From: Sarfraz Nawaz [mailto:[EMAIL PROTECTED] > Sent: 15 September 2006 10:20 > To: Michael Collett > Subject: Vanderbilt Acoustic Ranging on MicaZ > > > Hi Michael, > > I saw your emails in the tinyos-help mailing list archives about the > TestAcousticRanging application from Vanderbilt. I am also trying to get > it working on MicaZ but running into similar problems with the Timer that > you mentioned in your emails. Just wondering if you were able to get > things working and if you could offer some advice on how to fix these > issues. I'll really appreciate your help. > > Thanks for the time. > > Regards > > > -- > Sarfraz Nawaz > > PhD Student, > School of Computer Science and Engineering, > University of New South Wales, > Sydney 2052, Australia. > > Phone: +61 2 8374 5537 > Fax: +61 2 8374 5200 > Email: [EMAIL PROTECTED] > > Legal disclaimer: http://www.eng.unsw.edu.au/emaildis.htm > > > ------------------------------------------------------------------- > This e-mail and any attachments may contain confidential and/or > privileged material; it is for the intended addressee(s) only. > If you are not a named addressee, you must not use, retain or > disclose such information. > > NPL Management Ltd cannot guarantee that the e-mail or any > attachments are free from viruses. > > NPL Management Ltd. Registered in England and Wales. No: 2937881 > Registered Office: Serco House, 16 Bartley Wood Business Park, > Hook, Hampshire, United Kingdom RG27 9UY > ------------------------------------------------------------------- > -- Sarfraz Nawaz PhD Student, School of Computer Science and Engineering, University of New South Wales, Sydney 2052, Australia. Phone: +61 2 8374 5537 Fax: +61 2 8374 5200 Email: [EMAIL PROTECTED] Legal disclaimer: http://www.eng.unsw.edu.au/emaildis.htm ------------------------------------------------------------------- This e-mail and any attachments may contain confidential and/or privileged material; it is for the intended addressee(s) only. If you are not a named addressee, you must not use, retain or disclose such information. NPL Management Ltd cannot guarantee that the e-mail or any attachments are free from viruses. NPL Management Ltd. Registered in England and Wales. 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