Friday, September 19, 2008

New EOPD sensor from Hitechnic


Well the EOPD sensor has finnaly arrived and boy are we all happy. I just recently put up a post on Nxtasy asking if anyone has an EOPD(elictric optical proximity detector) and everyone said they were only out for a short period of time. Well that was 2 months ago. Now it is out. This EOPD sensor can work wonders. It looks similar to a normal light sensor but what it is a highly accurate sensor that can measure distances of up to 12 in. So now when you want to build a segway easy withought the complex programming of a gyroscopic sensor you can becasue the only other way was the US sensor and that was too slow, but with this sensor you don't have to worry about that becasue this is very accurate and fast.

Wednesday, September 17, 2008

Lego Mindstorms 1 Kit Wonders

Well Laurens Valk just put up a trailer for the book 1 Kit Wonders. Wow do those robots look good. This is a video lots of peole have been waiting for and now it is finally here. Remember this book is coming out November 4th in most places. The Video can be found here http://www.youtube.com/watch?v=LK2zovBIae8&eurl=http://ricquin.net/lego/laurens/books/index.htm

Polling over

Well the votes are in and we have a tie. More people prefer making rc lego with 2 NXT's or one NXT and a bluetooth dongle than power functions. Personnally I think 2 NXT's are the best but I did not vote. Make sure you vote because I want to know what you are thinking. I will leave up each poll for a week after the polling is closed so that people have a chance to look at the answers.

Tuesday, September 16, 2008

New Lego Stores Opening!



Three new LEGO Stores are opening in October!
King of Prussia Mall, King of Prussia, PA
South Shore Plaza, Braintree, MA
Arden Fair Mall, Sacramento, CA

In October, we will celebrate our Grand Openings with a weekend-long celebration featuring exclusive LEGO sets, collectible, limited-edition LEGO t-shirts and lots of other great offers! Plus, you can participate in a LEGO Master Builder Event, get a commemorative certificate and enjoy great discounts, available Grand Opening Weekend only!


Read below for more details!
LEGO Store Grand Opening Celebration
at King of Prussia Mall, PA
October 3 - 5
Mark your calendar for the Grand Opening Celebration of the new LEGO Store at King of Prussia Mall!

The highlight of the weekend is our 3-day Master Builder Event, where LEGO fans of all ages are invited to help a real LEGO Master Builder construct an 8-ft tall LEGO Yoda™ model! This event is free and fun for the whole family, and everyone who participates will get a free LEGO Star Wars Certificate of Achievement, while supplies last, plus a LEGO Store coupon!

Event Hours:
Friday, October 3: 11:00 am - 7:00 pm
Saturday, October 4: 10:00 am - 6:00 pm
Sunday, October 5: 11:00 am - 6:00pm
JC Penney Court, The Plaza

Plus, on Saturday October 4:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll recieve an exclusive, limited-edition LEGO Liberty Bell set! This set was created just for the opening of our King of Prussia Store, and is not available for sale! The Liberty Bell set features a real moving clapper and the famous crack!

And, on Sunday October 5:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll recieve an exclusive, limited-edition LEGO Minifigure T-Shirt! These shirts are available in child's sizes only, and were created exclusively to mark the Grand Opening of the King of Prussia LEGO Store!

King of Prussia Mall
160 N Gulph Rd
King of Prussia, PA 19406
LEGO Store Grand Opening Celebration
at South Shore Plaza, Braintree, MA

October 11 - 13
Mark your calendar for the Grand Opening Celebration of the new LEGO Store at South Shore Plaza!

The highlight of the weekend is our 3-day Master Builder Event, where LEGO fans of all ages are invited to help a real LEGO Master Builder construct an 8-ft tall LEGO Yoda™ model! This event is free and fun for the whole family, and everyone who participates will get a free LEGO Star Wars Certificate of Achievement, while supplies last, plus a LEGO Store coupon!

Event Hours:
Saturday, October 11: 10:00 am - 6:00 pm
Sunday, October 12: 11:00 am - 6:00 pm
Monday, October 13: 11:00 am - 7:00pm
Macy's Court

Plus, on Sunday October 12:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll receive an exclusive, limited-edition LEGO Baseball Player set! This set was created just for the opening of our South Shore Plaza Store, and is not available for sale! The baseball player features a red hat, red socks, white uniform and even includes home plate!

And, on Monday October 13:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll receive an exclusive, limited-edition LEGO Minifigure T-Shirt! These shirts are available in child's sizes only, and were created exclusively to mark the Grand Opening of the South Shore Plaza LEGO Store!

South Shore Plaza
250 Granite St
Braintree, MA 02184
LEGO Store Grand Opening Celebration
at Arden Fair Mall, Sacramento, CA

October 17 - 19
Mark your calendar for the Grand Opening Celebration of the new LEGO Store at Arden Fair Mall!


The highlight of the weekend is our 3-day Master Builder Event, where LEGO fans of all ages are invited to help a real LEGO Master Builder construct an 8-ft tall LEGO R2-D2™ model! This event is free and fun for the whole family, and everyone who participates will get a free LEGO Star Wars Certificate of Achievement, while supplies last, plus a LEGO Store coupon!

Event Hours:

Friday, October 17: 11:00 am - 7:00 pm
Saturday, October 18: 10:00 am - 6:00 pm
Sunday, October 19: 11:00 am - 6:00pm
Center Court

Plus, on Saturday October 18:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll receive an exclusive, limited-edition LEGO Gov. Stanford Steam Locomotive set! This set was created just for the opening of our Arden Fair Store and is not available for sale! The train engine features realistic details and moving parts, modeled after the famous Transcontinental Railroad engine!

And, on Sunday October 19:
Be one of the first 300 customers to spend $35 in the LEGO Store and you'll receive an exclusive, limited-edition LEGO Minifigure T-Shirt! These shirts are available in child's sizes only, and were created exclusively to mark the Grand Opening of the Arden Fair LEGO Store!

Arden Fair Mall
1689 Arden Way
Sacramento, CA 95815
About the LEGO Stores
Visit the LEGO Store near you to see the newest, hard to find and exclusive LEGO sets and fill up on the bricks and elements you need at the Pick a Brick wall! Plus, each month, you can participate in free, hands-on building events – ask your local store for details! The LEGO Stores are also available to host your child’s birthday party!

Monday, September 8, 2008

Tips for Dragstors Robots

OK, so you've probably built a NXT dragster before inspired by those fast racers right? Well now I will show you some tips on how to make a very fast and efficient dragster.

First is the gear ratio. This is very important. The 1:15 gear ratio is the start of the deficiency of your dragster. So you'll have to find a smaller ratio. I find that using the 1:8.333 ratio works the best with stock* parts. The bigger the gear for the drive and the smaller for the output is usually what you think but if you compare a perfect gear combination to a high gear combination the perfect gear would be crusing quickly while the high gear will be stalling every few seconds.

Next is wheel circumference. The phrase bigger is better fits here perfectly. You can use stock wheels and get 6 MPH out of it. (If you have enough track, 7 MPH is able to achieve.) Now find the largest wheel you have. The Green Exo-Force wheel is probably the largest. Why does this work? Because the larger the wheel, the bigger the circumference. The bigger the circumference, the more it travels in one rotation.

Now is the important part, you battery options. The Energizer E2 is probably you pick of choice. It is super light weight and can give a ton of boost. But the cost is not. If you are sticking with rechargeables but have a big fat wallet you might want to try the LEGO rechargeables, sure not exactly called fast charging or lots of power but it has a plug in charge that makes it easy for multiple runs. It is light to counter act the downsides. Now if you don't have a such big wallet and don't mind 120 grams (30 grams heavier than LEGO's rechargeable battery pack) then try the nice GP batteries. They are only sold in 3 stores in the US but they give 0.1 V more than the rechargeable (I pretty big difference). They also are not pricey but can withstand a huge load for a long time considering they are just normal batteries. My cheep 1300Mah batteries can withstand 3 amps for 20 min! That is more than 3 motors under complete stress. Though it is not recommended to stress all 3!

Now the weight comes to mind. The phrase bigger is better really doesn't fit here. You want to make your dragster as light but as strong as possible. Try only using essential elements and ignore the decorations. The decorations can produce drag and unstability of the NXT so just leave them behind. When your robot is traveling near 5 MPH and is only a few hundred grams, you want to try to keep it as aerodynamic as possible as the wind can effect it at this speed. But, don't ever keep strength out of your mind. Toque is lost due to the friction of the gears. The more friction the less energy is transferred to the wheels making it lose its speed dramatically. So strengthen the gear connections by placing beams on both sides and use 2 gears instead of one to increase torque to give it more power.

Also this last tip is to make the vehicle have only back and forth and have rubber front wheels. The swivel in the front makes it slippery and can make it slip and slide. The front swivel can also make it lose control when attempting to change directions. The swivel has to turn 180 and your robot is feeling that friction created by that 180 spin by that swivel and will make the dragstor do a uncontrolible spin. And if your robot is able to accelerate long enough it might crash!

That's about it for this time. I hope these tips helped you as I have been experimenting with my dragster traveling at a top speed of 6.7 MPH with only stock* wheels and mostly stock* elements (except for the front wheels and a extra 40 tooth to improve torque and allow steering).

* Stock means the stuff that comes with the set.

Friday, September 5, 2008

My first post

Well this is my first post on my blog. I am planning on putting a lot of the projects that I make with my LEGO Mindstorms NXT. Well here it is and if you want to contribute just let me know by sending an Email to megamindstorm101@gmail.com