Friday, January 20, 2012

Neato LIDAR Schematic!

A small first step to an open source LIDAR based off of the Neato XV-11 LIDAR...

Below is a first revision schematic of the Neato XV-11 LIDAR Piccolo board.  It was created by hand and I will post a video later explaining how it was done for the curious.  For the seasoned veterans just take a look at the schematic.

Some components were easy to identify and others were not so easy.  The transistors are basically a best guess based off of the minimal identifying marks on the SMT package.  I am not 100% sure how the laser diode control circuit works at this point so I will take some measurements of a live module to test my assumptions.  Based off what I know so far the cathode of the laser module is pulsed to power the laser and it is held slightly above 0V and then lowered closer to 0V momentarily to rapidly turn the laser on and off.

Stay tuned for a video explaining the whole process along with more details.  See CAD file at the bottom of page for raw schematic which was done using TinyCAD...  FREEWARE!!




14 comments:

  1. Awesome work. Can't wait for more info. Have you been able to work out what the DSP is doing to control the diode?

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  2. I will try to post more info and findings in the next week or two as I have time to take measurements based on the schematic. Hopefully I can find some time to make a video as well to explain how I created the schematic, and describe how different parts work.

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  4. Go on. Your work is excellent. Look forward for more infos. Maybe you must build and sell "micro" lidar for robotic use

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    1. I think an open source design would be awesome! Then we can ALL have one! :)

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  5. This may seem like kind of a duh comment, but scanners have linear image sensors & lenses in their scanheads & you can find them on craigslist. seems like a good place to start for diy since linear 2000+ pixel imaging chips run $50 on ebay. The lenses probably won't work for this application, but i'd imagine the imaging chips are pretty good.

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    1. Christine,

      I would say its a great comment. I have a scanner here I was going to take apart so I will check and see what it has inside!

      The only thing I would be concerned about is the read speed of the sensor in the scanner. You can actually get the linear image sensor from Panavision for about $14 in single quantities so it's not too bad. But I always like the scavenging for parts idea!

      Maybe I will do a google search to see if anyone has removed the sensor from a scanner and used it.

      On a side note, I usually like to stick with parts from a supplier because it can be hard to get a hold of a specific scanner or other device to tear apart after a year or so, and you never know what a manufacturer might change while in production so scavenging for parts is really a crap shoot. But great idea for a one-off build as you can get a lot of stuff for cheap.

      -Hash

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    3. Hash,
      you have told than it is possible to get Panavision sensor for 14$. Can you tell how to do it? Where did you find that price?
      I am thinking about selfmade LIDAR, but the only sensor which I can found and buy is TSL1401 (128 pixels).
      Here is my project (in Russian): http://roboforum.ru/forum10/topic12095.html

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  6. So whats next? Where to go from here in building a DIY lidar?

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    1. I see the plan as a few steps that need to be done.

      First, we need to create an Open Source project to write our own LIDAR firmware that will run on the Neato LIDAR hardware. We need people familiar with the TMS320 microcontroller, or people willing to learn! This will ensure that our hardware platform is sound for development purposes.

      Second, at the same time we can also be working on creating the electrical/mechanical design of an open source LIDAR loosely based on the Neato LIDAR. As I have already provided schematics that part is done. Just need to create some PCB's and a mechanical housing (easier said than done).

      I am willing to be part of a highly motivated team, but do not have the bandwidth necessary to take on this task alone!

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  7. Just to clarify, the 4 pin connector that comes out of the lidar is black/orange/brown/red. What is the pinout for that? GND, TX, RX, and 5v?

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    1. William,

      Black = GND
      Orange = LIDAR TX
      Brown = LIDAR RX
      RED = +5V

      Here is a link to the blog post on the HORIZ Board that feeds power to the Piccolo board (schematic above)

      http://random-workshop.blogspot.com/2011/11/reverse-engineering-neato-lidar.html

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