The king of machine tools is the lathe, and if the king has a heart, it’s probably the leadscrew. That’s the bit that allows threading operations, arguably the most important job a lathe can tackle. It’s a simple concept, really – the leadscrew is mechanically linked through gears to the spindle so that the cutting tool moves along the long axis of the workpiece as it rotates, allowing it to cut threads of the desired pitch.
But what’s simple in concept can be complicated in reality. As [Clough42] points out, most lathes couple the lead screw to the spindle drive through a complex series of gears that need to be swapped in and out to accommodate different thread pitches, and makes going from imperial to metric a whole ball of wax by itself. So he set about building an electronic leadscrew for his lathe. The idea is to forgo the gear train and drive the leadscrew directly with a high-quality stepper motor. That sounds easy enough, but bear in mind that the translation of the tool needs to be perfectly synchronized with the rotation of the spindle to make threading possible. That will be accomplished with an industrial-grade quadrature encoder coupled to the spindle, which will tell software running on a TI LaunchPad how fast to turn the stepper – and in which direction, to control thread handedness. The video below has some great detail on real-time operating systems on microcontrollers as well as tests on all the hardware to be used.
This is only a proof of concept at this point, but we’re looking forward to the rest of this series. In the meantime, [Quinn Dunki]’s excellent series on choosing a lathe should keep you going.
Continue reading “Benchtop Lathe Gets An Electronic Leadscrew Makeover”
“Where’s the any key?” Well, it’s right here. After running into trouble with the STM platform, [lukasz.iwaszkiewicz] went with the Texas Instrument C Series Launchpad to construct his “Any Key” HID device. He was able to make use of the TI TM4C123G LaunchPad’s extensive USB library which is laid out into four tiers – the very top tier being Device Class API. This gives the programmer the ability to implement simple devices with just a few lines of code. [lukasz.iwaszkiewicz] points out that ST does not have this option available.
The Any Key uses a host PC program that allows the user to enter keystrokes into a virtual keyboard. This information is then passed to the Any Key device. When it is pressed, it will push the recorded keystrokes back to the host PC. Simple, but effective!
The project is completely open source, and all files and code are available. Be sure to check out the video after the break demonstrating the Any Key in action.
Continue reading “Finally, Someone has found The Any Key”
Because Nixies, Decatrons, and VFD tubes really are that cool, [cubeberg] over on the 43oh forums designed an IV-18 clock for the TI Launchpad.
Like adafruit’s Ice Tube clock, [cubeberg]’s project uses a surplus Russian IV-18 VFD tube conveniently sourced on eBay. On the board, there are three buttons for changing the time and setting the alarm along with a MAX6921 VFD tube driver and a small switching regulator to boost the 5 Volts on the Launchpad to the 50 V the tube requires.
There was a little bit of space left on [cubeberg]’s PCB design, and he filled that space with a header for a buzzer and a temperature sensor. Right now, the code doesn’t support an alarm function and he’s still waiting on a few components to finish off the thermometer portion of the board, but it’s still the makings of a very nice clock.
If you’d like to grab your own Launchpad ice tube clock, [bluehash] is organizing a group buy for 430h forum members. If they can get 15 pieces built, the clock will cost less than $5/unit. Very cool, and very cheap when you consider TI is practically giving Launchpads away.
Last month, [Vinod] bought a pair of hobby servos on a whim. These servos sat on the shelf for a while until [Vinod] asked his friend what he should use them for. [Achu] suggested using the servos for a walking robot, so after checking out a few YouTube videos of some servo-powered walkers, [Vinod] built his own.
The robot is built around a TI Launchpad housing an MSP430 microcontroller. An extremely simple circuit (just some servos and a cap) power the robot along by alternating the direction the servos turn.
[Vinod]’s two-servo locomotion mechanism is very reminiscent of BEAM robots, extremely simple walking (or rolling) robots made out of just a few logic circuits. This TI Launchpad is in some ways even simpler; where [Mark Tilden]’s Walkman robot used several 74-series octal buffers, [Vinod]’s project is just a Lanuchpad and a pair of servos.
All the code is available on [Vinod]’s blog. Check out the demo video after the break.
Continue reading “Two motor walking robot with a TI Launchpad”
There are many microcontrollers available to make robots with, but few that are built with the exact features that you would need to construct one. Meet the [EMGRobotics MSP430G2553] robot controller board.
At $15 without the CPU or $17 with a [MSP430G2553] already plugged into the socket, this control board may make some Arduino enthusiasts take note for their next project. Besides a very attractive price (you’ll have to go to the home page to make a purchase), this board ships with a built in IR range sensor and accommodations to drive up to four hobby servo motors. If this isn’t enough for you, two 3 volt DC motors can be soldered directly to connections on the board and controlled independently and in either direction. In other words you don’t have to muck about with trying to build your own H-bridge circuit, it’s all taken care of for you!
The article shows it controlling a Hexbug spider. [EMGRobotics] has actually done something similar (and well-documented) before with this platform, so be sure to check out the post about hacking the Hexbug iteslf!
Experimentations with haptics
[Chris] sent in two videos (1, 2) documenting his experiments with haptic feedback. He’s recording the position of a DC motor and can either play it back or send it to another motor. It’s very similar to the kissing robot we saw earlier this year, but we’re not making any judgments.
Mobile Emergency Repeater go bag
[Nick], a.k.a. [KF5JAK] sent in a few pics of his emergency/disaster relief amateur radio go bag. With a 3G connection via a cell phone, the MER can be used with EchoLink.
Launchpad MIDI booster pack
Earlier this month we lamented the dearth of add-ons for the TI Launchpad. The folks on the 43oh forums just came out with a MIDI booster pack. Time to dust off that old Radio Shack keyboard, we guess.
Macro photography with OH GOD WHARGARBL
You know camera lenses work both ways, right? [Karl] has been experimenting with this very idea by mounting a camera lens backwards and running a few wires so it’s electrically connected as well. Check out an example shot.
Keeping tabs on your kids’ homework
[Janis] doesn’t live with his kids but he wanted to keep track of their homework. He set up a document scanner that sends those worksheets straight to his email inbox. All he has to do is annotate them and send them back. This guy’s doing it right.
For his first project using the TI Launchpad [VOJT4] built a lap timer and counter for slot cars. For us it’s always hardest to come up with the idea of what to build and we think he found a great one here.
Each time a car passes the finish line of the track it trips a reed switch that was hot glued to the underside of the track segment. Both reed switches have a capacitor to smooth out the inputs (is this acting as a hardware debounce?). The time and lap number are then pushed to a graphic LCD by the MSP430G2553.
You must be logged into the forum where [VOJT4] posted the project in order to see the images. Because of this, we’ve embedded them (including the schematic) after the break along with a demo video. But do take a look at his project thread to hear his thoughts and peruse the code he wrote.
Continue reading “Slot car lap timer/counter”