Skip to main content


Here's a steerable blimp using an RCX. The maker wants his next version to use an autonomously-programmed NXT with a single mylar envelope that could theoretically fly for days.

Here's the builder's full description:

"Using an RCX, 3 Motors, the Infrared Remote, Large trash bags, and lots of helium, my son and I created a steerable blimp.

Two of the motors controlled propellers (made from a LEGO propeller with larger blades made out of packaging plastic). The third motor controlled the tilt of the two propellers.

Each propeller can be separately controlled. For example, to rotate the craft, one propeller would be driven forward and the other backward.

Metal washers were used as ballast to try to achieve neutral buoyancy so the propellers could be used to raise or lower the craft as well as move about the room. Helium leaked out of the trash bags fairly quickly so the ballast had to be frequently adjusted.

With one load of helium, we had about 2 hours of flight time (starting with a lot of ballast and then removing it bit by bit over the two hours).

The use of the Infrared remote was a bit of a challenge as the controls were not very intuitive (e.g., frequently tilting the rotors in the wrong direction). Also, maintaining the line-of-site needed for the remote was a challenge.

In my next version, I'm planning to make the following changes:

- Use an NXT instead of an RCX and use bluetooth to remotely control the craft.

- Set up more intuitive controls.

- Replace the trash bags with one large mylar envelope. This should greatly increase the flight time from hours to days or even weeks.

- Set up one of the propellers to have the opposite pitch to have the two props cancel each other out when spinning in a vertical position.

- Add sensors and program the NXT for independent control."

Popular posts from this blog


2023 is the 25th Anniversary of the MINDSTORMS brand. For 25 years, MINDSTORMS has educated and inspired a generation of robot builders, both children and adults. Unfortunately, the LEGO Group decided to end the line on December 2022. Many ROBOTMAK3RS have been passionately involved with the development of MINDSTORMS through the MUP and MCP programs. Even with the newest Robot Inventor line, several ROBOTMAK3RS were invited to submit additional bonus models that were included in the official app. Regardless of the retirement of a major LEGO robotics product line, ROBOTMAK3RS continue to MAKE-SHARE-INSPIRE using all LEGO robotics platforms available to us. Here is the official statement from LEGO. Since its launch in September 1998, LEGO MINDSTORMS has been one of the core ‘Build & Code’ experiences in the company’s portfolio, carrying with it significant brand equity and becoming a stand-out experience for the early days of consumer robotics and leading to current Build & Code

Celebrating MINDSTORMS with a Remix Part 1

In honor of the 25th Anniversary of MINDSTORMS, we asked ROBOTMAK3RS to combine a LEGO set of their choice with a MINDSTORMS set. Here is what these five ROBOTMAK3RS came up with.  MINDSTORMS Chess Assistant by Arvind Seshan Overview: When you are new to chess, it can be a challenge to remember which pieces go where. Now, you can use machine learning and LEGO MINDSTORMS Robot Inventor to build a tool to help you learn where all the chess pieces go on the chess board. Sets used: LEGO® Iconic Chess Set (40174) and MINDSTORMS Robot Inventor (51515) Review: I really like how the chess set base can store all the pieces underneath and that the board neatly splits in half for handy storage. The chess pieces themselves are very sturdy and well built. My only criticism is the building of the box itself. It was quite difficult to see what pieces to use and since the entire box is made mostly of thin plates, it took a lot of time and patience. I would have liked the storage area to be sliding dra

Celebrating 25 Years of MINDSTORMS

In celebration of the 25th Anniversary of MINDSTORMS, we take a trip through history. Please also visit ROBOTMAK3RS Community every week as we highlight different projects all through 2023 in celebration of the anniversary. Some of the early history is based on the content shared by  Coder Shah  in our  MINDSTORMS EV3 Community Group . Some of the text and links may have been edited from his original posts for consistency and clarity.  1984 - Kjeld Kirk Kristiansen watched a TV program called "Talking Turtle," where MIT professor Seymour Papert demonstrated how children could control robot "turtles" using LOGO, a programming language he developed. 1988 - The collaboration between MIT and LEGO resulted in LEGO TC Logo in 1988, which allowed students to control LEGO models using computer commands. The video shows Papert demonstrating TC Logo. 1990 - LEGO TC Logo was hampered since the robots you built had to be tethered to a personal computer. LEGO and MIT