Humans have an innate knack for identifying food that is fit to eat. There’s a reason you instinctively enjoy fresh fruit and vegetables, but find maggot-infested rotting flesh offputting, for example. However, we like to automate as much of the food production process as possible so we can do other things, so it’s necessary to have machines sort the ripe and ready produce from the rest at times. [kutluhan_aktar] has found a way to do just that, using the power of neural networks.
The project’s goal is a straightforward one, aiming to detect ripeness in fruit and vegetables by monitoring pigment changes. Rather than use a camera, the project relies on data from an AS7341 visible light sensor, which is better suited to capturing accurate spectral data. This allows a better read of the actual light reflected by the fruit, as determined by the pigments in the skin which are directly related to ripeness.
Sample readings were taken from a series of fruit and vegetables over a period of several days, which allowed a database to be built up of the produce at various stages of ripeness. This was then used to create a TensorFlow model which can determine the ripeness of fruit held under the sensor with a reasonable degree of certainty.
The build is a great example of the use of advanced sensing in combination with neural networks. We suspect the results are far more accurate than could have reasonably be determined with a cheap webcam, though we’d love to see an in-depth comparison as such.
Believe it or not, it’s not the only fruit spectrometer we’ve featured in these hallowed pages. Video after the break.
Continue reading “Detecting Ripeness In Fruit And Vegetables Via Neural Networks” →
You don’t have to be an extinct mammal or a Millennial to enjoy the smooth, buttery taste of an avocado. Being psychic on the other hand is definitely an advantage to catch that small, perfect window between raw and rotten of this divaesque fruit. But don’t worry, as modern problems require modern solutions, [Eden Bar-Tov] and [Elad Goldberg] built the AvoRipe, a device to notify you when your next avocado has reached that window.
Taking both the firmness and color of an avocado as indicators of its ripeness into account, the team built a dome holding a TCS3200 color sensor as stand for the avocado itself, and 3D printed a servo-controlled gripper with a force sensor attached to it. Closing the gripper’s arms step by step and reading the force sensor’s value will determine the softness the avocado has reached. Using an ESP8266 as centerpiece, the AvoRipe is turned into a full-blown IoT device, reporting the sensor readings to a smartphone app, and collecting the avocado’s data history on an Adafruit.IO dashboard.
There is unfortunately one big drawback: to calibrate the sensors, a set of nicely, ripe avocados are required, turning the device into somewhat of a chicken and egg situation. Nevertheless, it’s a nice showcase of tying together different platforms available for widescale hobbyist projects. Sure, it doesn’t hurt to know how to do each part from scratch on your own, but on the other hand, why not use the shortcuts that are at our disposal to remove some obstacles — which sometimes might include programming itself.
Continue reading “AvoRipe Takes A Firm Grip On The Ultimate First World Food Problem” →
[Frank Howarth] found himself in need of a lamp for his dining room. Being of the maker persuasion, store-bought simply wouldn’t do. With a serious wood shop at his disposal, [Frank] took a trip down to the supermarket for inspiration.
Having picked out a particularly well-formed starfruit for his project, [Frank] didn’t want to spend an inordinately long time attempting to recreate the organic lumps and bumps in modelling software, Instead, Meshroom was used to create a model through photogrammetry. After several failed attempts, success was achieved by using a textured rotating table as a background, with the starfruit painted in matte grey and a final dusting of black speckle. This gave the software enough visual cues to accurately model the fruit’s geometry.
With a 3D model to hand, Fusion Slicer was then used to generate a model that could be constructed out of flat lasercut pieces. The cutting outlines were then generated and passed to Rhino for final tweaking. With everything ready, parts were cut out of plywood and a small mockup of a potential lamp design was created. [Frank] is currently workshopping the design with the inhabitants of the dining room, prior to the final build.
Photogrammetry and modern CAD tools make working with natural forms quick and easy. We’ve also seen the technology used for other purposes too, with [Eric Strebel] providing a great example on how to use it for reverse engineering.
The starfruit tag on Hackaday is pretty sparse, so if you’ve got a project, let us know. Video after the break.
Continue reading “A Fruity Approach To CNC Design” →
Our bodies are not like LEGO blocks or computers because we cannot swap out our parts in the living room while watching television. Organ transplants and cosmetic surgery are currently our options for upgrades, repairs, and augments, but post-transplant therapy can be a lifelong commitment because of rejection. Elective surgery costs more than a NIB Millenium Falcon LEGO set. Laboratories have been improving the processes and associated treatments for decades but experimental labs and even home laboratories are getting in on the action as some creative minds take the stage. These folks aren’t performing surgeries, but they are expanding what is possible to for people to do and learn without a medical license.
One promising gateway to human building blocks is the decellularization and recellularization of organic material. Commercial scaffolds exist but they are expensive, so the average tinkerer isn’t going to be buying a few to play with over a holiday weekend.
Let’s explore what all this means. When something is decellularized, it means that the cells are removed, but the structure holding the cells in place remains. Recellularizing is the process where new cells are grown in that area. Decellularizing is like stripping a Hilton hotel down to the girders. The remaining structures are the ECM or the Extra Cellular Matrix, usually referred to as scaffolding. The structure has a shape but no functionality, like a stripped hotel. The scaffolding can be repopulated with new cells in the same way that our gutted hotel can be rebuilt as a factory, office building, or a hospital.
Continue reading “Decellularization: Apples To Earlobes” →
If you’ve been to downtown San Francisco lately, you might have noticed something odd about the decorative trees in the city: they’re now growing fruit. This is thanks to a group of people called the Guerrilla Grafters who are covertly grafting fruit-bearing twigs to city tress which would otherwise be fruitless. Their goal is to create a delicious, free source of food for those living in urban environments.
Biology-related hacks aren’t something we see every day, but they’re out there. For those unfamiliar with grafting, it’s a process that involves taking the flowering, fruiting, or otherwise leafy section of one plant (a “scion”) and attaching them to the vascular structure of another plant that has an already-established root system (the “stock”). The Guerrilla Grafters are performing this process semi-covertly and haven’t had any run-ins with city officials yet, largely due to lack of funding on the city’s part to maintain the trees in the first place.
This hack doesn’t stop at the biological level, though. The Grafters have to keep detailed records of which trees the scions came from, when the grafts were done, and what characteristics the stock trees have. To keep track of everything they’ve started using RFID tags. This is an elegant solution that can be small and inconspicuous, and is a reliable way to keep track of all of one’s “inventory” of trees and grafts.
It’s great to see a grassroots movement like this take off, especially when it seems like city resources are stretched so thin that the trees may have been neglected anyway. Be sure to check out their site if you’re interested in trying a graft yourself. If you’re feeling really adventurous, you can take this process to the extreme.
Thanks to [gotno] for the tip!
[Hasbi Sevinç] is using perishable goods in his electronics project. The orange, tomato, and two apples seen above act as keys for the virtual piano. The concept is the same as the Makey Makey which is often demonstrated as a banana piano. This implementation uses an Arduino to read the sensors and to connect to the computer running the piano program.
You can see there’s a fair amount of circuitry built on the breadboard. Each piece of fruit has its own channel to make it into a touch sensor. The signal produced when your finger contacts the food is amplified by transistors connected in a Darlington pair. That circuit drives the low side of a optoisolator transmitter. The receiving side of it is connected the I/O pin of the Arduino. You can see the schematic as well as a demo clip after the break.
This use of hardware frees up a lot of your microcontroller cycles. That’s because projects like this banana piano use the timers to measure RC decay. [Hasbi’s] setup provides a digital signal that at most only needs to be debounced.
Continue reading “Fruit Piano Uses A Different Circuit Than The Makey Makey” →
[BiOzZ] built a pressure sensitive camera accessory to snap pictures at just the right moment. Before turning out all the lights the camera is set up with a twenty-second timer and a three-second exposure. The pressure plate doesn’t take the photo, but fires the flash to catch an image in the middle of the action.
The hack uses a piece of acrylic as the base of the pressure plate. A switch is constructed by placing aluminum tape on the base, and attaching a thin metal strip that is bent to add just a bit of spring. When an object is place on the plate the thin metal contacts the aluminum tape completing the circuit, a change in the weight breaks it. A simple circuit connects to this, using a relay to actuate the flash from a disposable camera. This is perfect for documenting the moment when you exercise that fruit-induced rage that has been consuming you lately.