High torque encoded DC motors for robots from car window motors

Hi! As I mentioned in my latest post on how to make Tiny Encoders for DC Motors, some time ago I went to a junkyard to salvage two powerful high torque DC motors from car window lifting systems to use in a robot. I had to take my own tools and dismantle the doors from an old Renault Laguna myself  to get the motors and then managed to negotiate with the seller to buy both motors for 25€, which I think was quite cheap.

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Tiny Encoders for DC motors

Hi again! Today I'll show you a small part of a project that I did a long time ago and, due to some changes of plans I didn't end up using. Anyway, maybe this small project might come up handy for you.
Some time ago I went to a junkyard to salvage two powerful high torque DC motors from car window lifting systems to use in a robot and had to make some encoders to put in them. The space where I could put them was really small so I had to find really small sensors and design a PCB for them in Kicad.
The sensors that I used were Vishay's TCUT1300 IR Transmissive Sensor with photo-transistor output. Following the sensor's datasheet I designed a small board (10x8mm) that would fit in the space that I had available.

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CNC Controller Board v2

As I said previously, I have been slowly developing my second CNC Machine, TheMaker2. To control the new CNC machine I developed a new board based on a PIC16LF877A since the L297's that I used on the first CNC controller board that I designed can be quite expensive here in Portugal and I had some PIC16LF877A samples lying around that with a few programming lines could do the same or even more than three L297 stepper motor controllers.

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Once again, the board design can be split in three parts:

1. Isolation - it has Vishay's CNY17-2 optocouplers to isolate the parallel port from the rest of the circuit;
2. Driver - a Microchips' PIC16LF877A drives three stepper motors in unipolar mode (if you prefer bipolar you can change the schematics and boards at your will);
3. Power Interface - a bunch of Vishay's SUP85N03 N channel FETs working as switches controlled by the PIC16LF877A.

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Homemade CNC: TheMaker2

Hi! As I previously said in my first post about my first Homemade CNC: TheMaker1, I was slowly developing a bigger, faster (didn't accomplish this part yet) and more robust CNC. Well, the development phase has finally come to an end and it is finally ready! :D In order to build a more rigid structure I decided not to build it with a moving gantry, but with a moving table on x axis and a fixed structure for y axis, which holds z axis. The build is based on this one.

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One of the main objectives was to make it low cost and believe it or not, with some scavenging involved I managed to build the whole structure with only 84.4€! :D Oh, and this cost still includes some spare materials! :P

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CNC Controller Board

In this post I'll make a short description of the CNC controller boards that I'm making available for you to download and use to control your own CNC. I'm posting 3 version of the same board, but only the first one has been really tested and has been working inside my CNC Control Box for a long time now (see my previous post Homemade CNC:TheMaker1). I'm 99% sure that the other boards will work too because they only have minor changes. I'll explain them to you in a few moments.

All the boards are made in Kicad. The design of the boards is based on the CNC3AX designs, but it uses other components that I had available at the moment that I made the board for my CNC. I advise you that I just wanted to get my CNC running, so I didn't make any careful selection of the most appropriate components and I didn't make the math to calculate the best values for the resistors. I just made it with the components that I had laying around. The boards design can be split in three parts:

1. Isolation - it has Vishay's 6N137 optocouplers to isolate the parallel port from the rest of the circuit;
2. Drivers - the ST Microelectronics' L297 drive the motors in unipolar mode (if you prefer bipolar you can change the schematics and boards at your will);
3. Power Interface - a bunch of Vishay's IRL510 N-channel FETs working as switches controlled by the L297 Drivers.

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Homemade CNC: TheMaker1

Hi! In the following lines I'll present a project that has taken a very long time to complete: my homemade CNC machine. From the first tests and tryouts with various materials to the actual machine 2 years have passed. More important stuff always made me delay the development of the CNC. However, I estimate that the total amount of time was 3 weeks. I think CNCs are a big challenge for anyone since it involves a lot of mechanical, electronics and computer engineering (although we can bypass the computer engineering part by using available software). It was a challenge for me, with lots of frustration along the way because of my lack of skill to make the parts with the few tools I had, but now I can happily say "Mission Accomplished!":D.

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CNC Software Toolchain for Linux

Hi! Some time ago I made a post about My Home Lab where I showed a small CNC that I built. In the same post I said that someday I would post some details on the software toolchain and that's exactly what I'm going to do in this post.

The process of using a CNC to make 3D parts follows three simple steps:

1. Design the parts.

To design the parts I use HeeksCAD. HeeksCAD is a free, open source, CAD application written by Dan Heeks.

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