For my Mechatronics class my team and I were assigned to build an automated can crusher. The crusher is to be loaded with 10 uncrushed cans and then output 10 crushed cans in under 2 minutes. The following video demonstrates our can crushing device.
Our team still needs to solve the issue of loading cans into our crusher through some sort of hopper device, but for now, we are satisfied with our can crusher.
A few tech specs:
6″ throw, 1.5″ bore diameter pneumatic Cylinder
Operating Pressure: 100 psi
Control is achieved using a 4-way solenoid valve paired with a L298 based motor driver.
An Arduino Mega provides the smarts.
Valentino Braitenberg is an Italian-Austrian neuroscientist. In his book, entitled “Vehicles: Experiments in Synthetic Psychology”, he performs thought experiments creating vehicles which, while simple in nature, exhibit complex behaviors such as fear, love, aggression and optimism. His vehicles are simple, with the simplest consisting of a single sensor and single motor. This simplicity makes it easy for someone to construct one of his vehicles. While Braitenberg like behaviors can be programmed into any robot with the proper sensors and actuators it is a more interesting challenge to construct a Braitenberg vehicle in hardware, as described in his thought experiments.
Due to the interesting nature of Braitenberg’s vehicles, the CMU Robotics Institute has provided funding to a project to create Braitenberg-esque vehicles that would then go on display in the Robotics Institute. I’m acting as co-project leader, coordinating with a graduate student in the Machine Learning program who obtained the funding for the project. I’m hoping the project will produce 5 to 6 artistic Braitenberg inspired creations. I’ve spent some time thinking about possible things I could create and I’m excited to see what ideas other people come up with after I present the project at the Robotics Club’s general body meeting.
More to come on Braitenberg in the coming weeks as projects get started.
During the previous semester, as part of a class project, we built urban search and rescue robots. We built the robots using the LEGO NXT set. For our robot I built a custom pan-tilt mechanism to mount the camera we were provided with.
The pan-tilt used two servos and a custom microntroller board to interface the servos with the NXT. The controller board also allowed for LEDs (used for illumination) to be turned on and off.
We controlled the robot over a bluetooth link via joystick. It turns out that the NXT brick times out after 15 min no activity and that an open bluetooth does not count as activity.
In short, this project ruined my childhood and made me hate LEGOs. The constraints of the project made it very difficult to build an effective robot. However, a simple combination of wheels and treads let a build a robot to fit the constraints.
As part of a class project, for Micro/Nano Robotics, we’re building an ornithoper. The above video shows an example of the flapping mechanism.
For this project we will be building an ornithopter that uses passive wing pitching to increase the amount of total lift. As the video shows, the flapping mechanism is complete. The wings should be built within the next few days.
We’ve mounted Stairbot in a hanging position so we could perform some testing on its legs. We’ve discovered some issues with our servos, and we keep blowing some of them up. We’re not sure if it’s an issue with the design, or if the servos are bad.
A video of the legs cycling through some motions:
We also have some pictures of the hanging setup:
Stairbot is getting closer and closer to completion. The above render is what the final version should look like. We’ve decided to laser cut a lot of acrylic to build most of the leg and body structure.
We’ve ordered all of our electronics, and we should be receiving them soon. Then we can start actually programming and getting gaits set up. Our goal is to have the construction mostly completed by the end of the month, and start working on some basic motion control.
Below are some images from the build process.
I’m in a class called Introduction to Robotics. In this class we have labs where we make robots to do things using the LEGO NXT Mindstorms kits. (Part of) Our current assignment is to make a robot that can follow a fairly complex line. In our team, I’m the Mechanical Engineer, so I built the robot. Our Computer Scientist, Rich, wrote a really sweet line following program based on the general algorithm our group came up with.
I’m not going to reveal the black magics he used in his program, or our general algorithm, but, from the video you can probably deduce the general idea. The line it follows is complex, containing both a 90 degree bend and a hairpin. As you can also see in the video, the robot could follow this line indefinitely until its batteries die.
During Build 18 I managed to slap together a simply chassis for our micro colony robots. It was super simple, made of some plastic and hot glue, but, it was able to hold everything on it.
Here are some pictures:
As you can see it isn’t very big, not much larger than my cell phone. I used 3 4-40 machine screws which let us slide the sensor board into place and tuck all of the electronics underneath. I really like the 4-40 screws for stacking feature and it is something I would like to retain for the next revision of our chassis.
The next revision will also have a mount for the servos, instead of them just being tacked in place with hot glue. It was a quick and dirty build, but, it got the job done.
Earlier this evening the Stairbot Team (a CMU Robotics Club project I head) began construction of our robot. Thus far we have only done initial part sizing (machining stock down to the size we will need for the part). Below are pictures of the machined parts and the schematic for them. The schematic was created by Mike Ornstein who has done all of the CAD work for Stairbot thus far. Our grant submission can be found on his site: here.
I’ll follow up with more details about Stairbot later this week.
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I’ve managed to complete 1 sensor board for the build 18 project. The basic idea of the sensor board its to let the robots figure out their relative positions. The sensor board consists of 5 IR emitter/detector pairs. The basic idea is one robot will turn on its IR emitters and the other robots will use their dtectors to figure out their relative position based on which detector registers seeing the IR.
The sensor board is based, in concept, on the one found here: http://ipvs.informatik.uni-stuttgart.de/BV/swarmrobot/tikiwiki-1.9.2/tiki-index.php?page=sbII . However, our sensor board uses only 5 IR emitter/detectors and we do not use ours for communication, only for relative positioning.
We plan to have at least 2 of these working, hopefully 4 in total.
Here is a gallery of images from the construction of the board:
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