Skip to main content

Email question from a student Part 2


Okay, here's one method for determining if the sensors are returning all True values or all False value or a mixture of values.... This means in my previous post that we're talking about a condition of (1 - 1 - 1) to get the Switch block to execute a True path - any other combination will have the Switch block execute the False path.


One of the easiest ways to do this is to use a Logic block configured to do an AND operation. Read over the Logic block's help files to learn about the other options (OR, XOR, NOT), but for now all you need to know is that the Logic block will take two logic values (one in data plug A and one in data plug B). The AND operation simply looks at the two values and returns a logic value of its own (coming out of the last data plug, called Result). If both values (A and B) are True, then the Result is True. If both values (A and B) are False then the Result is False. If one or the other (A or B) is False, then Result is False. So, the only way you'll get a Result value of True from a Logic block is if both A and B data plugs have a True value coming in.


Next, we take that Result from the first Logic block and run it a second Logic block (data plug B in my picture) configured to do an AND operation. I take the final sensor's logic value (the Touch sensor in my picture) and connect that sensor's Yes/No data plug to data plug B on the second Logic block. I then run a wire out of the second Logic block's Result data plug into a Switch block's data plug.


See if you can figure out what happens now that you understand that both Logic blocks are performing AND operations on the A and B values sent to them. By using just two Logic blocks, you can check to see if all 3 sensors are reporting True or all 3 are reporting False. All it takes is one sensor to report a False and the Switch block will receive a False signal. Follow along and test this little bit of programming and you'll figure it out.


Jim

Popular posts from this blog

Celebrating MINDSTORMS with a Remix - Part 3

The ROBOTMAK3RS continued their celebration of the 25th Anniversary of MINDSTORMS through these Fall and Winter remix projects. Each ROBOTMAK3R was tasked with selecting one LEGO set of their choice and combining it with a MINDSTORMS set. Below are the five amazing models they came up with. Braill3 by Jerry Nicholls Braill3 is an EV3-based LEGO Braille bricks reader. This robot uses its fingertip, made from three touch switches, to read messages written using the LEGO Braille bricks and will speak out what it detected. If it sees a simple maths problem it will attempt to solve it and give the answer as well. To learn more about the process of creating this machine, read Jerry's blog . Braill3 can be viewed here . Set Review: The Braille Bricks set is well thought out. The ratios of the letters is suitable for general use and the addition of some punctuation and arithmetic operators is excellent. There is a card showing what bricks there are and their quantities, but no form of sort

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 2

The ROBOTMAK3RS continued their celebration of the 25th Anniversary of MINDSTORMS through these summer and fall remix projects. Each ROBOTMAK3R was tasked with selecting one LEGO set of their choice and combining it with a MINDSTORMS set. Below are the five amazing models they came up with. Remote controlled material handle r by Jozua van Ravenhorst (aka Mr Jo) This remix combines the LEGO Technic Material Handler (42144) with MINDSTORMS EV3 (31313) It uses the power of pneumatic cylinders to move objects around. By using a bluetooth remote control, very precise movements can be made with this model. Touch sensors in the base chassis prevent the turret twisting the cables that go through the turntable to much. The program has several protections to prevent over pressurizing the system for each of the 3 individual pumps and valves that control the 2 booms and claws. The real version of this machine is mostly used in waste material sites to bring the material to machines that sort and