Chainsaw Powered Bicycle

July 11, 2009 by Gerrit Coetzee 37 Comments

chainsawbike

We’ve covered weed whacker bicycles before and you can even buy 66cc conversion kits now. [geoff390] posted a few videos over on YouTube about another motor option. In the first video embedded below, he goes over the basic parts of his bike. The chainsaw motor is mounted to the side of the back tire and a metal drive wheel extending from the chainsaw shaft makes contact with it. The motor assembly is mounted on a hinge and the friction between the drive wheel and the back tire is adjusted with a turnbuckle. He posted a more detailed second video in which he goes over some of the finer details of the bike and some of the issues he’s had. Continue reading “Chainsaw Powered Bicycle” →

Cheap Cup Holder Laptop Tray

July 11, 2009 by Gerrit Coetzee 52 Comments

bigfront

[Michael Davis] sent in his homemade laptop tray. He does a lot of traveling in his Toyota Tacoma and was looking for a good way to mount his laptop inside. Unfortunately, [Michael] soon discovered that commercial laptop trays can be very expensive and difficult to install. He saw an opportunity in the empty cup holder in his car. Fifteen dollars worth of PVC pipe fittings and a piece of plywood later he had a laptop tray.

Intel 8008 Clock

July 7, 2009 by Gerrit Coetzee 11 Comments

Every year [Len Bales] designs and builds a new clock. His 2006 clock runs on the classic Intel 8008 microprocessor. The design is definitely not for the faint of heart, but he includes all code, diagrams and a good description on his site. The project is an interesting look into the not-so-distant past of computing. While the function of the project is a clock, it is actually a fully programmable 8008 computer running at 500khz with 16k of memory space and 4io ports. [Len] also links a lot of useful 8008 resources for anyone wanting to tackle a project of their own.

Clever Stair Climbing Robot

July 2, 2009 by Gerrit Coetzee 22 Comments

[youtube=http://www.youtube.com/watch?v=QReb1hLfdbE]

Stairs are one of the most commonly faced mobility challenges for a robot. This robot’s design eliminates the need for a complex drive train or computer, and instead uses a clever mechanical design to climb stairs. Version three of the robot uses five servos modified for continuous rotation, a Picaxe28, sharp IR sensors, and bump sensors.

[via BotJunkie]

Motors And Microcontrollers 101

June 29, 2009 by Gerrit Coetzee 7 Comments

[youtube=http://www.youtube.com/watch?v=WnWJki-zwsE]

[Humberto] from NerdKits sends in the newest addition to their excellent collection of videos. This video goes over the basics of DC motor control with microcontrollers. They begin by showing nine experiments and observations that can be done by the average hacker with a multimeter, motor, LED, and jumperwire. Using the results from these they show how to model and calculate the properties of a motor. Lastly, it shows how to control a motor using PWM. They have supplemental text and demonstration code for an ATmega168 on their website.

Automated Paintball Sentry

June 26, 2009 by Gerrit Coetzee 32 Comments

[youtube=http://www.youtube.com/watch?v=7vYKwih8Izk]

Reader, [Ben Godding], sends in the video for his senior design team’s automated paintball sentry. The frame is made of plasma cut aluminum. The paintball gun uses a custom hopper mounted remotely from the gun body. It has two webcams offering a 160 degree field of vision, and the image processing is done by a dual core pentium CPU booting windows xp off a compact flash card. The computer interfaces with the 1/4scale RC servos using a PIC24. The paintball sentry can either be configured via a computer GUI when a monitor is available or a baclkit keypad and 4×20 charachter display in the field.

Related: [Jared Bouck]’s paintball gun turret

Wireless Arduino Cat Food Dispenser

June 24, 2009 by Gerrit Coetzee 14 Comments

catfooddispenser

Reader, [Andres Leon], has two adorable cats with very specific dietary needs. Instead of altering his schedule, he donned his hacking hat and designed a very solid cat food dispenser. The dispenser consists of a rotating drum with a slot in it and a PVC pipe Y-fitting to distribute the food evenly. The brains of the machine is an Arduino Deumillanove and an XBee module. The unit can be controlled by a web interface or it can run completely standalone. [Andres] ran into a problem where the drum’s resistance to turning varied based on how much food was inside. He solved this with a clever laser position indicator. A piece of plywood is lined up with the slot at the top so that whenever the slot is facing up it keeps the laser from shining on a photoresistor. The cats were afraid of the servo noise at first, but now they run to their bowls whenever they hear it.