PF IR Receiver as Wireless Touch Sensor

Here are the details on the trick that I used in my Battle Tank project to get the NXT to read sensor input from the Power Functions remote control. See the "Method 1". This allows the NXT to see the IR receiver as a single touch sensor, which is actually quite easy to do if you have the two wires needed (PF Extension Wire and RCX Conversion Cable). The "Method 2" was an earlier and much more complex way to get full control from both levers (9 states).

You only get one touch sensor out of this, but with a little timing trick in the NXT program, I made the single PF lever control two NXT-triggered functions on the Battle Tank. A quick press and release of one lever triggers the scissor stabber with one NXT motor, and a press and hold of the same lever triggers the dart gun with another NXT motor. This leaves the other lever on the same channel open to run a PF M-motor in both directions to implement the unfolding saw blade (same M-motor folds/unfolds via a worm gear while also spinning the blade by up-gearing). Then the other IR receiver is attached to the two PF XL-motors to do the driving on another channel.

It looks like you could extend this trick to get two touch sensors by connecting the other half of the IR receiver to a second sensor port on the NXT, but this doesn't work. Pressing either lever ends up triggering both touch sensors. Wondering what was going on here, I consulted Philo, who kindly explained that the whole setup is electrically questionable to begin with because the PF and NXT sides don't share a common ground, but it ends up working and being safe with one sensor, but attaching two creates a strange current flow and also results in a short circuit condition if the levers are pushed in opposite directions. So don't bother trying that...

MINDSTORMS Retires!

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 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

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

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