A team of Cornell students have designed and built their own electronic boxing trainer system. The product of their work is a game similar to Whack-A-Mole. There are five square pads organized roughly into the shape of a human torso and head. Each pad will light up based on a pre-programmed pattern. When the pad lights up, it’s the player’s job to punch it! The game keeps track of the player’s accuracy as well as their reaction time.
The team was trying to keep their budget under $100, which meant that off the shelf components would be too costly. To remedy this, they designed their own force sensors. The sensors are basically a sandwich of a few different materials. In the center is a 10″ by 10″ square of ESD foam. Pressed against it is a 1/2″ thick sheet of insulating foam rubber. This foam rubber sheet has 1/4″ slits cut into it, resulting in something that looks like jail bars. Sandwiching these two pieces of foam is fine aluminum window screen. Copper wire is fixed the screen using conductive glue. Finally, the whole thing is sandwiched between flattened pieces of corrugated cardboard to protect the screen.
The sensors are mounted flat against a wall. When a user punches a sensor, it compresses. This compression causes the resistance between the two pieces of aluminum screen to change. The resistance can be measured to detect a hit. The students found that if the sensor is hit harder, more surface area becomes compressed. This results in a greater change in resistance and can then be measured as a more powerful hit. Unfortunately it would need to be calibrated depending on what is hitting the sensor, since the size of the hitter can throw off calibration.
Each sensor pad is surrounded by a strip of LEDs. The LEDs light up to indicate which pad the user is supposed to hit. Everything is controlled by an ATMEGA 1284p microcontroller. This is the latest in a string of student projects to come out of Cornell. Make sure to watch the demonstration video below. Continue reading “Boxing Trainer Uses DIY Force Sensors”
Last week we wrote about the guys over at TwoBitCircus and their upcoming STEAM Carnival. This Thursday we managed to make it down to the Hacker Preview day where they showed us all the toys and games that will be exhibited over the weekend.
The preview day went pretty well until the evening, when unexpected power problems occurred and the site lost power for a little while. But this is why you have a preview day right? Organizer [Brent Bushnell] even commented that he should have put a BETA badge on the ticket. Thankfully the outage coincided with the food truck arriving so everyone stopped for a burger.
Sadly all the fire based pieces were not active on the preview day since they didn’t have the appropriate safety measures in place yet, but they did get to show us most of their games. My personal favorites were the Hobby Horse Racing, and the Laser Foosball.
Here’s a quick run down of some of the stand out pieces.
Continue reading “STEAM Carnival Hacker Preview Day”
Graphics accelerators move operations to hardware, where they can be executed much faster. This is what allows your Raspberry Pi to display high definition video decently. [Andy]’s latest build is a 2D sprite engine, featuring hardware accelerated graphics on an FPGA.
In the simplest mode, the sprite engine just passes commands through to the LCD. This allows for basic control. The fun part sprite mode, which allows for sprites to be loaded onto the FPGA. At that point, you can show, hide, and move the sprite. By overlapping many sprites, you something like the demo shown above.
The FPGA is from Xilinx, and uses their Block RAM IP to store the state of the sprites. The actual sprite data is contained on a 128 Mb external flash chip, since they require significant space.
The game logic runs on a STM32 Cortex M4 microcontroller which communicates with the FPGA and orders the sprites around. The FPGA then deals with generating frames and sending them to the LCD screen, freeing up the microcontroller.
If you’re wondering about the LCD itself, it’s 3.2″, 640 x 360, and taken from a Ericsson U5 Vivaz cellphone. [Andy] has a detailed writeup on reverse engineering it. After the break, he gives us a video overview of the whole system.
Continue reading “Sprite Graphics Accelerator on an FPGA”
We don’t want to call it a challenge because we fear the regulars at DEFCON can turn our piece of hardware into a smoking pile of slag, but we are planning to bring a bit of fun along with us. I’ll be wearing this classy headgear and I invite you to hack your way into the WiFi enabled Hackaday Hat.
I’ll be wearing the hat-of-many-scrolling-colors around all weekend for DEFCON 22, August 7-10th in Las Vegas. You may also find [Brian Benchoff] sporting the accessory at times. Either way, come up and say hello. We want to see any hardware you have to show us, and we’ll shower you with a bit of swag.
Don’t let it end there. Whip out your favorite pen-testing distro and hack into the hat’s access point. From there the router will serve up more information on how to hack into one of the shell accounts. Own an account and you can leave your alias for the scoreboard as well as push your own custom message to the hat’s 32×7 RGB LED marquee.
You can learn a bit more about the hat’s hardware on this project page. But as usual I’ve built this with a tight deadline and am still trying to populate all the details of the project.
As the Jerusalem mini Makerfaire approached, [Avishay] had to come up with something to build. His final project is something he calls ASTROGUN. The ASTROGUN is a sort of augmented reality game that has the player attempting to blast quickly approaching asteroids before being hit.
It’s definitely reminiscent of the arcade classic, Asteroids. The primary difference is that the player has no space ship and does not move through space. Instead, the player has a first person view and can rotate 360 degrees and look up and down. The radar screen in the corner will give you a rough idea of where the asteroids are coming from. Then it’s up to you to actually locate them and blast them into oblivion before they destroy you.
The game is built around a Raspberry Pi computer. This acts as the brains of the operation. The Pi interfaces with an MPU-9150 inertial measurement unit (IMU). You commonly see IMU’s used in drones to help them keep their orientation. In this case, [Avishay] is using it to track the motion and orientation of the blaster. He claims nine degrees of freedom with this setup.
The Pi generates the graphics and sends the output to a small, high-brightness LCD screen. The screen is mounted perpendicular to the player’s view so the screen is facing “up”. There is a small piece of beam splitting glass mounted above the display at approximately a 45 degree angle. This is a special kind of glass that is partially reflective and partially translucent. The result is that the player sees the real-world background coming through the glass, with the digital graphics overlaid on top of that. It’s similar to some heads-up display technologies.
All of the electronics fit either inside or mounted around a toy gun. The display system was attached with a custom-made fiberglass mount. The code appears to be available via Github. Be sure to watch the video of the system in action below. Continue reading “ASTROGUN is like Asteroids on Steroids”
Building a multiplayer network game with multiple Raspberry Pis can be very difficult. Doing it in assembly is outright insane! This is exactly what a group of first year students at Imperial College London did; they created a network based multiplayer Tetris game for the Raspberry Pi.
[Han], [Piotr], [Michal], and [Utsav] have created this entire game from bare metal assembly, and it only consists of 4000 lines of code! The code is well documented, so be sure to look through their Github repository. This project is a great reference for those looking to learn bare metal assembly and networking. They even chose to use the old NES controllers, a very nice touch. While we have featured what seems like a million different Tetris games in the past, this is the first multiplayer version. See Tetris Duel in action in the video after the break!
This is a shout-out to all of you students out there. Take the time to create quality documentation for your class project, and upload it to the internet. Not only is it a great resume boost, but it could very well end up on Hackaday!
Continue reading “Tetris Duel with the Raspberry Pi”
We’ve all been there. You are having fun walking around the carnival when you suddenly find yourself walking past the carnival games. The people working the booths are taunting you, trying to get you to play their games. You know the truth, though. Those games are rigged. You don’t know how they do it. You just know that they do… somehow.
Now you can put your worries to rest and build your own carnival game! [John] built his own “Bass Master 3000” style carnival game and posted an Instructable so you can make one too.
The game is pretty straightforward. You have a giant fish-shaped target with a wide open mouth. You take hold of a small fishing reel with a rubber ball on the end. Your goal is to cast the ball out and hit the fish in its big mouth. If you hit the mouth, you get to hear a loud buzzer and see some flashing lights. The system also uses a webcam to take a candid photo of the winner. A computer screen shows all of the winners of the day.
The brain of the system is an Arduino Yún. The Yún is similar to an Uno but it also has some extra features. Some good examples are an Ethernet port, a wireless adapter, and an SD card slot. The mouth sensors are just two piezo elements. Each sensor is hooked up to the Arduino through a small trim pot. This allows you to dial in the sensitivity of each sensor. The lights and the buzzer are controlled via a relay, triggered by a 5V digital pin on the Arduino.
The Yún actually has a small on-board Linux computer that you can communicate with from inside the Arduino environment. This allows [John] to use the Yún to actually take photos directly from a web cam, store them on the local SD card, and display them on a local web server. The web server runs a simple script that displays a slide show of all of the photos stored on the card.
The final piece of the game is the physical target itself. The target is painted using acrylic paint onto a small tarp. The tarp is then attached to a square frame made from PVC pipe. The mouth of the fish is cut out of the tarp. A large piece of felt is then placed behind the hole with the piezo sensors attached. A short length of copper pipe helps to weigh down the bottom of the felt and keep it in place. The important thing is to make sure the felt isn’t touching the tarp. If it touches, it might be overly sensitive and trigger even when a player misses.
Now you know how to build your own Bass Master 3000 carnival game. Whether you rig the game or not is up to you. Also, be sure to check out a video of the system working below. Continue reading “Build a Bass Master 3000 Carnival Game”