Motion Activated Super-Squirter Stands Guard

October 18, 2017 by Steven Dufresne 14 Comments

Thieves beware. If you prowl around [Matthew Gaber]’s place, you get soaked by his motion activated super-squirter. Even if he’s not at home, he can aim and fire it remotely using an iPhone app. And for the record, a camera saves photos of your wetted-self to an SD card.

ESPino, ArduCAM UNO and voltage converter boards

The whole security system is handled by three subsystems for target acquisition, photo documentation, and communications. The first subsystem is centered around an ESPino which utilizes a PIR sensor to detect motion. It then turns on a windscreen washer pump and uses pan and tilt servos to squirt water in a pattern toward the victim.

The target acquisition hardware also sends a message to the second subsystem, an ArduCAM ESP8266 UNO board. It takes a burst of photos using an ArduCAM Mini Camera mounted beside the squirter outlet. The UNO can also serve up a webpage with a collection of the photos.

The final subsystem is an iPhone app which talks to both the ESPino and the UNO board. It can remotely control the squirter and provide a video feed of what the camera sees.

One detail of the build we really enjoyed is the vacuum relief valve he fabricated himself. It prevents siphoning through the pump when it’s not on. Don’t miss a demo of the squirter in action after the break.

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Zeroing CNC Mills With OpenCV

December 15, 2016 by Brian Benchoff 45 Comments

For [Jay] and [Ricardo]’s final project for [Dr. Bruce Land]’s ECE4760 course at Cornell, they tackled a problem that is the bane of all machinists. Their project finds the XY zero of a part in a CNC machine using computer vision, vastly reducing the time it take to set up a workpiece and giving us yet another reason to water down the phrase ‘Internet of Things’ by calling this the Internet of CNC Machines.

For the hardware, [Jay] and [Ricardo] used a PIC32 to interface with an Arducam module, a WiFi module, and an inductive sensor for measuring the distance to the workpiece. All of this was brought together on a PCB specifically designed to be single-sided (smart!), and tucked away in an enclosure that can be easily attached to the spindle of a CNC mill. This contraption looks down on a workpiece and uses OpenCV to find the center of a hole in a fixture. When the center is found, the mill is zeroed on its XY axis.

The software is a bit simpler than a device that has OpenCV processing running on a microcontroller. Detecting the center of the bore, for instance, happens on a laptop running a few Python scripts. The mill attachment communicates with the laptop over WiFi, and sends a few images of the downward-facing camera over to the laptop. From there, the laptop detects the center of the bore in the fixture plate and generates some G-code to send over to the mill.

While the device works remarkably well, and is able to center the mill fairly quickly and without a lot of user intervention, there were a few problems. The camera is not perfectly aligned with the axis of the spindle, making the math harder than it should be. Also, the enclosure isn’t rated for being an environment where coolant is sprayed everywhere. Those are small quibbles, and these problems could be fixed simply by designing and printing another enclosure. The device works, though, and really cuts down on the time it takes to zero out a mill.

You can check out the video description of the build below.

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ArduCAM Introduces A Third Party Raspberry Pi

July 18, 2016 by Brian Benchoff 43 Comments

There are hundreds of ARM-based Linux development boards out there, with new ones appearing every week. The bulk of these ARM boards are mostly unsupported, and in the worst case they don’t work at all. There’s a reason the Raspberry Pi is the best-selling tiny ARM computer, and it isn’t because it’s the fastest or most capable. The Raspberry Pi got to where it is today because of a huge amount of work from devs around the globe.

Try as they might, the newcomer fabricators of these other ARM boards can’t easily glom onto the popularity of the Pi. Doing so would require a Broadcom chipset. Now that the Broadcom BCM2835-based ODROID-W has gone out of production because Broadcom refused to sell the chips, the Raspberry Pi ecosystem has been completely closed.

Things may be changing. ArduCAM has introduced a tiny Raspberry Pi compatible module based on Broadcom’s BCM2835 chipset, the same chip found in the original Raspberry Pis A, B, B+ and Zero. This module is tiny – just under an inch square – and compatible with all of the supported software that makes the Raspberry Pi so irresistible.

Although this Raspberry Pi-compatible board is not finalized, the specs are what you would expect from what is essentially a Raspberry Pi Zero cut down to a square inch board. The CPU is listed as, “Broadcom BCM2835 ARM11 Processor @ 700 MHz (or 1GHz?)” – yes, even the spec sheet doesn’t know how fast the CPU is running – and RAM is either 256 or 512MB of LPDDR2.

There isn’t space on the board for a 2×20 pin header, but a sufficient number of GPIOs are broken out to make this board useful. You will fin a micro-SD card slot, twin micro-USB ports, connectors for power and composite video, as well as the Pi Camera connector. This board is basically the same size as the Pi Camera board, making the idea of a very tiny Linux-backed imaging systems tantalizingly close to being a reality.

It must be noted that this board is not for sale yet, and if Broadcom takes offense to the project, it may never be. That’s exactly what happened with the ODROID-W, and if ArduCAM can’t secure a supply of chips from Broadcom, this project will never see the light of day.

Truly Versatile ESP8266 WiFi Webcam Platform

January 24, 2016 by Elliot Williams 33 Comments

[Johan Kanflo] built a sweet little ESP8266-based wireless camera. It’s a beautiful little setup, and that it’s all open and comes with working demo code is gravy on the cake! Or icing on the potatoes. Or something.

[Johan]’s setup pairs an ESP8266-12 module with an Arducam, which looks like essentially an SPI breakout board for the ubiquitous small CMOS image sensors. The board naturally has a power supply and headers for programming the ESP module as well as connectors galore. Flash in some camera code, and you’ve got a custom WiFi webcam. Pretty slick.

But since [Johan] designed the ESP-8266 board with standard female headers connecting to the ESP, it could also be used as a general-purpose ESP dev board. [Johan] built a few daughterboards to go along with it, including a bed-of-nails ESP8266 tester (since you can never tell when you’re going to get a dud ESP unit) and WiFi-to-RFM69 radio bridge. That’s two awesome applications for a tidy little system, and a reminder to design for extensibility when you’re laying out your own projects.

We’ve previously covered [Johan]’s Skygrazer project, which tracks planes as they fly overhead and displays them on a gutted old Mac. Is it any surprise, then, that he’s also created an ADS-B-controlled moodlight? This guy is on fire!