Building an automatic bicycle transmission in a week

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Every year, the ECE department of Carnigie Mellon University hosts Build18, an engineering festival intended to get students out of the classroom and into the workshop. [Andrew Toth] along with team members [Jenna MacCarley], [Peter McHale], and [Nicolas Mellis] have been busy this last week putting together an automatic bicycle transmission.

Most cyclists agree that a cadence of 80 … Read the rest

Retrotechtacular: Fluid Coupling

retrotechtacular-fluid-coupling

We realize the transmission fluid of an automobile’s automatic transmission is used to transfer the power from the engine to the drive shaft. But after watching this Department of Defense video from 1954 we now have a full understanding of the principles involved in fluid coupling. Like us, you probably have seen a diagram of a transmission which shows … Read the rest

Plantenna: the plant antenna

The back story behind [Mike] experimenting with plants as AM radio transmission antennas antennae is rather interesting and worth the short read. But for those who just want the facts, [Mike] took an ATMega324, modified the PWM output into a sinusoidal AM signal (using a simple form of RLC circuitry), and connected the circuit to a plant no plants Read the rest

LEGO automatic transmissions

[AviatorBJP] is building some impressive automatic transmissions using LEGO parts. Your best bet is to check out his YouTube channel as he’s got a slew of videos related to topic. We’ve embedded test footage of first and second generation vehicles as well as the most recent flywheel design after the break. But we’re getting ahead of ourselves, let’s look at … Read the rest

Double clutch transmission model

[Alan] did an extraordinary job building a computer controlled model gearbox. His project from several years back is based on a dual-clutch Direct Shift Gearbox that was developed for VW and Audi vehicles. His design uses a gear head motor to provide the locomotion to this transmission. Shifting is computer controlled through serial cable, with servo motors providing the … Read the rest

Disabling GM’s manual skip shift

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GM, in an effort to make their cars slightly more eco friendly, added a feature that puts your car in 4th gear when cruising along in 1st under certain conditions. This is apparently despised by many owners. I is despised so much, that you can buy a commercial product to disable it. That product costs between $20 and $40. Jalopnik … Read the rest