In the 1950s the major Hollywood studios needed impressive cinematic technologies for their epic movies, to both see off the threat from television, and to differentiate themselves from their competitors. For most of them this meant larger screens and thus larger frame film, and for Paramount, this meant VistaVision. [Steve Switaj] is working on one of the original VistaVision cameras made for the studio in the 1950s, and shares with us some of the history and the work required to update its electronics for the 2020s.
VistaVision itself had a relatively short life, but the cameras were retrieved from storage in the 1980s because their properties made them suitable for special effects work. This mostly analog upgrade hardware on this one had died, so he set to and designed a PIC based replacement. Unexpectedly it uses through-hole components for ease of replacement using sockets, and it replaces a mechanical brake fitted to the 1980s upgrade with an electronic pull back on the appropriate reel motor.
The whole thing makes for an interesting delve into some movie history, and also a chance to see some tech most of us will never encounter even if we have a thing for movie cameras.
[Debasish Dutta] has designed a few weather stations in the past, and this, the fourth version of the system has had many of the feature requests from past users rolled in. The station is intended to be used with an external weather sensor unit, provided by Sparkfun. This handles wind speed and direction, as well as measuring rainfall. A custom PCB hosts an ESP32-WROOM module and an Ai-Thinker Ra-02 LoRa module for control and connectivity respectively. A PMS5003 sits on the PCB to measure those particulate densities, but most sensors are connected with simple 4-way I2C connectors. Temperature, humidity, and pressure are handled by a BME280 module, UV Index (SI1145), visible light (BH1750) even soil humidity and temperature with a cable-mounted SHT10 module.
All this is powered by a solar panel, which charges a 18650 cell, and keeps the show running during the darker hours. For debugging and deployment, a USB-C power port can also be used to provide charge. A 3D printed Stevenson screen type enclosure allows the air to circulate amongst the PCB-mounted sensor modules, without hopefully too much moisture making it in there to cause mischief.
On the data collection and visualization side, a companion LoRa receiver module is in progress, which is intended to pass along measurements to a variety of services. Think Home Assistant, ESP home, and that kind of thing. Software is still a work in progress, so maybe check back later to see how [Debasish] is getting on with that?
This kind of multi-sensor hosting project is nothing new here, here’s a 2019 Hackaday prize entry along the same lines. Of course, gathering and logging measurement data is only part of the problem, visualization of those measurements is also important. Why not use a mechanical approach, such as a diorama?
When thinking about forests being endangered by human activity, most people would immediately think of the rainforest. Below the ocean surface, there’s another type of forest is in danger: the kelp forests off the coast of northern California. Warming sea water has triggered an explosion in the population of purple sea urchins (Strongylocentrotus purpuratus) which devour kelp at an alarming rate. It’s estimated that 90% of kelp forests have been lost to the urchins along a 350 km stretch of coastline.
The fix is as simple as getting rid of the urchins, but collecting the millions of spiny creatures manually isn’t realistic. Luckily, [RobotGrrl] designed just the tool for this task: Otter Force One, an autonomous underwater robot that can gather the aquatic interlopers and put them in a bag for removal. The device is still under development, but progress so far has been promising. The basic idea is to identify an urchin using machine vision, then dislodge it with a water jet, and finally to use a suction pump to pull it inside the machine and store it in a bag.
A prototype made from 3D printed components is currently being used to test the idea. Its motors are driven by an ESP32 with a motor controller, with the system powered by a set of beefy lithium batteries. Tests with plastic urchin models confirm that the suction mechanism works, though the water jet and machine vision systems still need to be tested. But even without these in place the Otter Force One can still be used by human divers to improve their urchin-gathering efficiency.
We’ll definitely keep an eye on this project, and hopefully see it evolve into a fully-automated urchin hunter. Underwater pest-control robots are not completely new: we already saw a laser-powered delouser for use on salmon farms. There are also robotic starfish and octopuses.
Landslides can be highly dangerous to both people and property. As with most natural disasters, early warning can make all the difference. [Airpocket] has built a cheap, affordable system that hopes to offer just that.
The system relies on a network of sensors built with Sony Spresense controllers, built into solar garden light enclosures which provide a watertight enclosure and a sustainable power supply. The controllers are paired with accelerometers to detect movement, and communicate over a WiSUN connection back to a Raspberry Pi 4B base station. When a deployed sensor station detects movement, it sends a message back to the base station, which sounds the alarm that a landslide may be imminent.
Early testing shows the concept works in theory. In practice, some improvements to reduce power draw and increase communication reliability are required. However, it’s a solid proof of concept for a simple landslide warning system.
Early warning is always key when it comes to things like landslides, tsunamis, and earthquakes. In fact, the US Geological Survey has done its own work on predicting earthquakes and providing early warning, too. Video after the break.
Continue reading “Hackaday Prize 2022: DIY Landslide Warning System”
These days, we’re all running around toting smartphones and laptops that could always use a bit more charge. Portable battery packs have become popular, and [Anuradha] has designed one that packs plenty of juice to keep everything humming.
The pack is designed to be charged via solar panels, at 18 V and up to 5 A of current. It’s intended to work with a Maximum Power Point Tracking module to ensure the maximum energy is gained from the sunshine available. For storage, the pack relies on 75 individual 18650 lithium cells, arranged with 3 cells in series, each with 25 in parallel (3s25p). They’re spot welded together for strength and good conductivity. Nominally, the output voltage is on the order of 10-12 V. The included battery management system (BMS) will allow an output current up to 100 A, and the pack can be used with an AC inverter to power regular home appliances.
Overall, it’s a tidy pack that’s more than capable of keeping a few devices charged up for days at a time. If you’re building something similar yourself, though, just be sure to package it well and keep it protected. So many lithium batteries can quickly turn fiery if something goes wrong, so store and use it appropriately! Fear not, however – we’ve got a guide on how to do just that.
Clothes dryers are great, and a key part of modern life, but they do use a lot of energy. [Mike Rigsby] decided to see if there was a more efficient method of drying clothes that could compete with resistive heating for efficiency. Thus, he started work on an ultrasonic clothes dryer.
In early testing, he found ultrasonic transducers could indeed blast droplets of moisture away from fabric, effectively drying it. However, unlike heat, the ultrasonic field doesn’t effectively permeate through a pile of clothes, nor can it readily be used with a spinning drum to dry many garments at once.
[Mike]’s current experiments are centered around using a basket-type system, with a bed of ultrasonic transducers at the bottom. The idea is that the basket will shake back and forth, agitating the load of clothing and allowing the different garments to effectively contact the transducers. It’s still a work in progress, but it’s an interesting approach to the problem. We’d love to see a comparison of the energy use of a full-scale build versus a regular dryer.
We’ve heard of the ultrasonic drying concept before, too, with the Department of Energy researching the matter. It could just be that we’ll all be using ultrasonic dryers in decades to come!
Running on a treadmill is a great way to workout, but what if the effort you put in could be put to use? This treadmill generator from [Amitabh Shrivastava] does just that.
The build starts with a regular old treadmill, which has a motor inside typically used to power the tread. Instead, the motor’s control electronics were removed, and it was repurposed to work as a generator. The output from the treadmill’s DC motor was fed directly to a DC-DC converter. This was then fed to an inverter that generates 120 V AC, which can power appliances that use up to 20-25W based on [tinkrmind’s] running performance.
It’s a fun way to generate power during a workout. If you don’t want your treadmill’s monitor to die in the middle of a Friends rerun, you’ll have to dig deep on those long runs. We’ve seen similar builds before too, with exercise bikes being a popular method of generating electricity. In fact, that’s [Amitabh]’s next project! Video after the break.
Continue reading “Hackaday Prize 2022: Treadmill Becomes Human-Powered Generator”