Featured Parts: Axles

Lego axles, in addition to connecting pegs, will be a crucial element of any robot you choose to construct. Whether used for structural support, or connecting two wheels along a single axis, lego axle beams have hundreds of important applications.

Axles come in about a dozen different sizes, and they geometry (unsurprisingly) meshes well with other lego blocks. It's not easy to determine spacing rules for beams, because most of the time spacial distances are dictated by the axle itself!

In my post about differential drives, we detailed how you can connect wheels on two separate axles; however keeping them aligned in the same order, spinning independently. You can also use wheels on the same axle, so that it will spin by itself along with the attached wheels, however this construct has many limitations when it comes to application in advanced topics.

As mentioned above, the geometrical construction of axles coincide nicely with corresponding lego parts. Here's an example of a gear run through an axle, all held in place by a supporting beam block. I thought it illustrated the different relationships between the parts nicely:

1000th Pageview!

A big thank you to everyone who's contributed towards this, and I'm proud to report that Mindstorm Mechanics has just received its 1000th pageview. I know this isn't really a post, but I just wanted to thank everybody for taking the time and reading the musings of a obsessed teen.

Thank you to all.

Video: Lego Cube Solver

Found this really cool video on youtube of a cube solver. This has some pretty advanced programming, but I also liked the interface the user created. I'll try and do a larger write up on it in a few days, but till then- enjoy!

Featured Parts: Connecting Pegs

Note: This is the first post in a series meant to help familiarize people with different parts abundant in many mindstorm sets. Send me feedback!

Mindstorms do a pretty good job of giving you total flexibility among design. One thing that sets Lego's apart from other competitive starter robotic kits is a pretty simple part: the connector peg.

While coming in many different variants, the two most common connector pegs are silver and black

Non-friction

Friction

These pegs are the simplest way to connect two beams, creating a degree of motion which is usually essential in most robots, however simple.

 Silver, or non-friction pegs do exactly as the name suggests, and spin freely within the slots on the beams they're inserted in. Usually, they are the peg of choice for adding a part that undergoes large amounts of motion (i.e. Wheels, levers, etc.)

Black pegs are sturdier, and when inserted into beams, will lock two beams together, providing limiting the amount of movement possible.

New Ideas

Hey everyone, so I wanted to see if any of you guys had a robot you'd like to see. Any applications/programming/purpose is acceptable, and if you had any questions I'll try to answer them as well.

Comment below or email me at ashwin.johri@gmail.com for your suggestions/questions!

Thanks

Walking With Mindstorms

Making a walking robot is another unique challenge that can be tackled with Mindstorms. The above picture is a set of legs I built, adapting a design I saw in this book.

I explain how the above system works in this video:

The other important concept to keep in mind as you design a walking robot, is COG; or center of gravity. Because only one foot of your robot will be on the ground at a given time, you'll either need to find a way to shift the COG over a single side, or you'll need to alternate the leg placements on either side, allowing for a successful walk, devoid of awkward falls and lurches.

My Lego Mindstorms Creations

Really really really cool video I found. This guy details his mindstorm creations, and some of them are really neat designs. Check it out!