3779 A place to share, learn, and grow... en-US Fri, 22 Jan 2016 00:17:16 +0000 http://bbpress.org/?v=1.0.2 q http://forums.leaflabs.com/search.php http://forums.leaflabs.com/topic.php?id=1885#post-11739 Sat, 14 Jul 2012 20:55:52 +0000 brijesh 11739@http://forums.leaflabs.com/ <p>A quick update. Have finished the layout and about to send the board to fabrication.</p> <p>I have shared pictures of 3d model, schematics, cost etc at sparkfun thread.<br /> <a href="http://forum.sparkfun.com/viewtopic.php?f=14&amp;t=32645" rel="nofollow">http://forum.sparkfun.com/viewtopic.php?f=14&amp;t=32645</a></p> <p>Soon will start work on software, will be back with tons of questions. In fact I have a question right now. Where can I get Maple code base that works with STM32F4. I understand that the code base is probably still under development.</p> <p>Cheers<br /> brijesh </p> http://forums.leaflabs.com/topic.php?id=1885#post-11214 Mon, 11 Jun 2012 14:09:12 +0000 mbolivar 11214@http://forums.leaflabs.com/ <blockquote><p> I have not looked at the maplelib yet, do you have code there for DCMI peripheral?</p> </blockquote> <p>No, there isn't DCMI support right now. <a href="http://leaflabs.com/docs/libmaple/contributing.html">Patches welcome</a>. </p> http://forums.leaflabs.com/topic.php?id=1885#post-11211 Mon, 11 Jun 2012 13:41:01 +0000 brijesh 11211@http://forums.leaflabs.com/ <p>mbolivar,</p> <p>I have not looked at the maplelib yet, do you have code there for DCMI peripheral?</p> <p>Thanks </p> http://forums.leaflabs.com/topic.php?id=1885#post-11210 Mon, 11 Jun 2012 13:39:27 +0000 brijesh 11210@http://forums.leaflabs.com/ <p>Hello Thomas,</p> <p>I did look at Olimex board. I contacted them asked if they had datasheet for the camera module and they said they don't have it.<br /> Also the form factor is not conducive for small robot. So developing this new board. </p> http://forums.leaflabs.com/topic.php?id=1885#post-11208 Mon, 11 Jun 2012 12:33:51 +0000 mbolivar 11208@http://forums.leaflabs.com/ <blockquote><p> I do not see any specific interface for a Camera module. I guess you are not planning on camera interface as of now? </p></blockquote> <p>That's correct. We've used the DCMI peripheral, and it's nice, but the high pin count on the chips that fully support it means DCMI support won't be part of the initial Maple II release. </p> http://forums.leaflabs.com/topic.php?id=1885#post-11194 Sun, 10 Jun 2012 04:05:48 +0000 ThomasB 11194@http://forums.leaflabs.com/ <p>Hi Cheers,</p> <p>Interesting Project!<br /> Do you know the STM32-P407 board from olimex?<br /> Not very compact, because it's more a 'All-In what's thinkable' board<br /> but it includes a STM32F4 and a onboard camera module, so maybe interesting for you.<br /> Here the link to the schematic: <a href="http://www.olimex.com/dev/ARM/ST/STM32-P207/STM32-P207-SCHEMATIC-REV-A.pdf" rel="nofollow">http://www.olimex.com/dev/ARM/ST/STM32-P207/STM32-P207-SCHEMATIC-REV-A.pdf</a></p> <p>best</p> <p> Thomas </p> http://forums.leaflabs.com/topic.php?id=1885#post-11179 Fri, 08 Jun 2012 19:48:30 +0000 brijesh 11179@http://forums.leaflabs.com/ <p>Hello,</p> <p>I just came to know that you guys are developing next version of Maple using STM32F4 device. I saw the schematics posted in one of the forum posts. I do not see any specific interface for a Camera module. I guess you are not planning on camera interface as of now?</p> <p>I just started to work on a project to build low cost vision module using STM32F4. I put together my idea in a few slides which you can see at</p> <p><a href="https://docs.google.com/presentation/d/1gqUJGU0NmZUGGmHDdDbCDIJePcvL9S4tyn_3nyUN_LA/edit" rel="nofollow">https://docs.google.com/presentation/d/1gqUJGU0NmZUGGmHDdDbCDIJePcvL9S4tyn_3nyUN_LA/edit</a></p> <p>Also a discussion at Sparkfun forum.<br /> <a href="http://forum.sparkfun.com/viewtopic.php?f=14&amp;t=32645" rel="nofollow">http://forum.sparkfun.com/viewtopic.php?f=14&amp;t=32645</a></p> <p>This project is still at initial stage, I am working on the schematics. It would be a good idea to use Maple IDE and maplelib. In that regard are there any specific hardware requirements for IDE and madplelib?</p> <p>My design currently is very minimal, not even using external crystal oscillator. I want to keep the design very simple so that I can get the first prototype out quickly and at low cost.</p> <p>Appreciate your thoughts and feedback.</p> <p>Cheers<br /> brijesh </p> http://forums.leaflabs.com/topic.php?id=257&page=2#post-4919 Wed, 01 Jun 2011 14:29:47 +0000 ridgebackred 4919@http://forums.leaflabs.com/ <p>brijesh,<br /> It would be great to be able to use a Maple Mini on the single task of laser range finding and reporting results back over the SPI or i2c bus. Keep us posted! </p> http://forums.leaflabs.com/topic.php?id=257#post-4918 Wed, 01 Jun 2011 12:12:19 +0000 brijesh 4918@http://forums.leaflabs.com/ <p>Hello Guys,</p> <p>I have had same thoughts about low cost laser range finder. I went through the same steps of trying to find a suitable camera and camera interface.</p> <p>Finally ended up trying with Taos Inc's 128*1 linear array sensor.<br /> <a href="http://www.taosinc.com/ProductDetails.aspx?id=3" rel="nofollow">http://www.taosinc.com/ProductDetails.aspx?id=3</a></p> <p>Initially I tried to hack something together on a bread board. That did not work as the laser and image sensor have to be rigidly mounted, small disturbances result in large errors.</p> <p>So ended up designing and building a custom board with lens and laser mounting. I just got the boards fabricated and will be firing them up soon. By the way I am also using STM32 processor on the board, but it is lower end one STM32F100C4.</p> <p>If you guys are still interested in the this project(after 7 months), I will keep you guys posted. If someone wants to work on it, just let me know.</p> <p>Cheers </p> http://forums.leaflabs.com/topic.php?id=257#post-1931 Fri, 22 Oct 2010 16:52:40 +0000 poslathian 1931@http://forums.leaflabs.com/ <p>oh yeah! Will have to check in to those sensors, thanks! </p> http://forums.leaflabs.com/topic.php?id=257#post-1930 Fri, 22 Oct 2010 15:53:30 +0000 gbulmer 1930@http://forums.leaflabs.com/ <p>Anyway, back to the Laser rangefinder. </p> <p>Apitina and Omnivision make sensors at a reasonable price (sub $30 at one off prices), which support windowing.</p> <p>At 48MHz pixel transfer rate (e.g. one of the less capable Aptina's), 3600 frames/second (10 frames at 360 positions) would be a 115 x 115 pixel square, which should be big enough to encompass the laser dot if it is keeping track of where things are going.</p> <p>Some of those image sensors support 96MHz clock rate, so 115x115pixels should be a reasonably conservative estimate.</p> <p>Push the data straight into an FPGA for initial processing, and it should give reasonable distance feedback 360 degrees around, at 10 sweeps/second.</p> <p>Do any of LeafLabs have contacts in an engineering department? They could probably make a reasonable prototype mechanism for you to experiment with.</p> <p>Some of the papers suggest that integrating this sort of 3D distance data with traditiomal image/vision data gives very high quality object recognition and navigation. With a few Oaks, and some low-cost cameras, you might have a pretty good low-speed DARPA-challenge-style sensor system for well under $1000, maybe well under $300.</p> <p>Just a thought ;-) </p> http://forums.leaflabs.com/topic.php?id=257#post-1929 Fri, 22 Oct 2010 15:40:52 +0000 gbulmer 1929@http://forums.leaflabs.com/ <p>Well you folks seem to manage okay, but maybe it's those Border Cafe Fajitas, and Hornitos Margarita's that keep them neuron's poppin' and jivin' !-)</p> <p>(while as I was doing the estimate, I realised I needed to raise the 7000 an extra few powers of 10 to get to yotta-ops, so that's why your visual processing neurons are so fast :-) </p> <p>I was a bit surprised at 5ms/neuron-firing, how (relatively) little processing power was available for 'real-time' vision processing. Still a lot, but not an amazing amount (any more). </p> http://forums.leaflabs.com/topic.php?id=257#post-1923 Fri, 22 Oct 2010 12:08:17 +0000 poslathian 1923@http://forums.leaflabs.com/ <p>I think MIT neurons are actually a bit slower, due to the inevitable burn out effect. </p> http://forums.leaflabs.com/topic.php?id=257#post-1916 Thu, 21 Oct 2010 19:27:17 +0000 gbulmer 1916@http://forums.leaflabs.com/ <p>Okie - </p> <blockquote><p>you meant 10^9 neurons? </p></blockquote> <p>I am really, really sorry about this, ...<br /> no, 10^99 neurons for me, you can speak for yourself (urggh)</p> <p>It's about 100,000,000,000, i.e. 10^11 neurons, so about 10^10 for vision, with a 'fan-out' of 7,000?</p> <p>An average neuron can fire in 5ms, so an MIT neuron, is probably quicker, say about 2ms?<br /> Flicker stops being a big problem arond 50Hz, so 10 sequential neuron events?<br /> In theory one neuron might trigger 7000^9 other neurons in that time, or 4x10^34 triggers, so all 10^10 neurons could get involved, doing 4x10^24 ops = 4 yotta-ops!</p> <p>A friend of a friend has got something like time of flight working<br /> <a href="http://www.photon.org.uk/activity/Programme/page_41480.html">Real time low cost pseudo-random noise continuous wave lidar</a> </p> http://forums.leaflabs.com/topic.php?id=257#post-1906 Thu, 21 Oct 2010 18:52:07 +0000 poslathian 1906@http://forums.leaflabs.com/ <p>These high speed cameras are simply amazing, but nearly as expensive as youd expect (10-200k$). But i think youre right about windowed output on cheaper consumer image sensors. Lets try and find one that does what we want. I wouldnt be too surprised if someone makes an inexpensive sensor that has single-scan-line output mode for just this sort of thing. </p> <p>Of course, you could also try and get time of flight working ;) </p>