TI Launchpad Adds Computer Control To A Robot Arm

[Eric Gregori] had an OWI535 toy robotic arm. Although cheap (coming it at around $30) the arm is only set up to be used via a wired control box. [Eric] knew he could do better by adding computer control via a TI Launchpad and motor driver peripheral.

The arm has shoulder, elbow, and wrist joints, a rotating base, and a gripper. All of these are actuated by 3V DC motors and have just two control wires. [Eric’s] motor driver add-on for the Launchpad works great in this case. It’s got three FAN8200 dual motor driver chips on board so it can control up to six motors. Once he made the hardware connections it’s just a matter of sending the commands to the Launchpad via its USB interface, but you will also need to use a larger microcontroller than comes with the Launchpad. Here he’s chosen an MSP430G2553.

In order to make things a little bit more fun he also wrote a GUI for controlling the arm from the computer. He used RobotSee, a programming language that lets you use an image of the hardware, and overlay the controls on top of it. Now he just needs to make this into a web interface and he can have a smartphone controlled crane game.

Don’t forget to check out the video after the break. Continue reading “TI Launchpad Adds Computer Control To A Robot Arm”

Slot Car Lap Timer/counter

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”