Ever feel like someone is watching you? Like, somewhere in the back of your mind, you can feel the peering eyes of something glancing at you? Tapping into that paranoia, is this Computer Science graduate project that was created during a “Tangible Interactive Computing” class at the University of Maryland by two bright young students named [Josh
As you’ve probably gathered from the title, this project uses a Microsoft Kinect to track the movement of nearby people. The output is then translated into actionable controls of the mounted eyeballs producing a creepy vibe radiating out from the feline, robot poster.
Continue reading “Creepy Cat Eyes with a Microsoft Kinect”
Having the right tool for the job makes all the difference, especially for the types of projects we feature here at Hackaday. [Jan_Henrik’s] must agree with this sentiment, one of his latest projects involves building a tool to generate a PWM signal and test servos using an Attiny25/45/85.
Tools come in all kinds of different shapes and sizes. Even if it might not be as widely used as [Jan_Henrik’s] earlier work that combines an oscilloscope and signal generator, having a tool that you can rely upon to test servos and generate a PWM can be very useful. This well written Instructable provides all the details you need to build your own, including the schematic and the necessary code (available on GitHub). The final PWM generator looks great. For simple projects, sometimes a protoboard is all you need. It would be very cool to see a custom PCB made for this project in the future.
What tools have you build recently? Indeed, there is a tool for every problem. Think outside the (tool) box and let us know what you have made!
Servos seem to be the go-to option when adding motors to hobby projects. They’re easy to hack for continuous rotation for use in a robot, but with the control board intact they are fairly accurate for position-based applications. But do you know how the hardware actually works? [Rue Mohr] recently published an article that looks at the inner world of the servo motor.
As you know, these motors use a voltage, ground, and signal connection for control. The position of the horn (the wheel seen on the servos above) is dependent on that control signal. The duty cycle of a 20 ms pulse decides this. Inside the housing is a control board capable of measuring this signal. It’s got a chip that monitors the incoming PWM pulses, but that’s only half of the equation. That controller also needs feedback from the horn to know if its position is correct or needs to be changed. Integrated with the gear box that connects the motor to the horn is a potentiometer. It’s resistance changes as the horn turns. Knowing this, it is possible to fine tune a servo by altering that resistance measurement.
Here’s a fantastic project that lets to drive a hexapod around the room using an RC controller. [YT2095] built the bot after replacing the servo motors on his robot arm during an upgrade. The three cheapies he had left over were just begging for a new project, and he says he got the first proof-of-concept module put together in about an hour. Of course what you see above has gone through much improvement since then.
The three motors are epoxied together, with the one in the middle mounted perpendicular to the motors on either side of it. Those two are responsible for the front and rear leg on each side, with the third motor actuating the two middle legs. It’s a design we’re already familiar with having seen the smaller Pololu version. You might want to check that one out as there’s some slow motion video that shows how this works.
[YT2095] added control circuitry that includes an RF receiver. This lets him drive the little bot around using a transmitter with four momentary push switches on it. We love the idea of using copper clad for the foot pads.