Static Equilibrium

Equilibrium is when forces acting on an object are equal so their net force equals zero, by this I mean that opposite forces acting on an object are equal. Although equilibrium has a net force of 0 and acceleration of 0 but it doesn't mean that they are not moving an object at equilibrium is either at rest and staying at rest, or in motion and continuing in motion with the same speed and direction.

Static means unmoving or the act of being stationary. So that means that static equilibrium is when an objects net value is 0  and they don't move and stay stationary.

This models a baby on a board suspended by two adults like how a
 beam bridge suspends a car/truck .

My Bridge

For my bridge I have decided to either make a truss bridge or an arch bridge for my project already i have made a few bridge bases and have already built two bridges to test 

I have decided t use these truss bridge designs because some are fairly easy to make and all will supply a decent amount of support so i can achieve the goal. After researching discovered the bridges that were able to hold a significant amount of weight were truss bridges that had curves in them or arc bridges with triangles and truss bridges that had rigid squares and triangles that

The types of truss bridges I am testing are:

The Parker Truss

Pratt Truss

Brown Truss

I am thinking of also testing this type of bridge it is a mix of a truss and arc bridge.

Bowtring Truss (Arc)

Bridges

A bridge is a structure that connect two points of a road, rail, or track, it suspends the roads from two sides of land usually over a body of water. Bridges are a commonplace item to see while driving so people don't realize how complex building a bridge really is. Architects and engineers have to incorporate how forces like tension (the force of pulling apart two points of an object), torsion ( the force of twisting two points of an object oppositely), compression( the force of pushing together two points of an object), and shear effect (the force of pulling one point of an object upwards and one point downwards) effect their bridge to make sure it doesn't buckle, curve, or snap.

The forces of Tension, Compression, Shear, and Torsion on a block of wood.

A box girder bridge a larger form of a beam bridge

The first bridge is a beam bridges the simplest type of bridges and can be found in a variety of sizes like a small wood bridge to cross over a stream or a large one that can stretch over a river, large beam bridges have pillars that hold up segments of the bridge they are called box girder bridges. The beam bridge is the most common bridge used today because it is simple and doesn't need that much resources and is thought to be the first type of bridge ever made. A single beam spanning any distance has compression and tension acting on it so if enough weight is added to a length of a beam bridge it starts to bend because the force of compression on top of that segment and the force of tension on the bottom of it increases and if the forces get too great the bridge will buckle and snap

  Cartoon shows compression acting at the top of bridge and tension acting on the bottom

A Deck and Through Truss Bridge

The second type of bridge is a truss bridge, which is a bridge that has a structure that forms triangles which is called a truss. This structure can go above (through) or below (deck) the roadway, and the truss allows the bridge to become more rigid and prevent compression and tension. The truss is able to make a more rigid bridge because the triangles allow forces like compression and tension to spread over a larger area and not just on one beam like how a snowshoe spreads your weight over a larger area so you don't sink in the snow. Truss bridges are reliable and use up minimal resources which makes them one of the most common forms of bridges and one of the oldest.

A tied arch bridge (above) and can be held up by wires

The third type of bridge is an arch bridge like the truss bridge it helps spread out the weight so it doesn't buckle or snap and the arch can be above (tied arch) or below the roadway.  A tied arch bridge though does not 

An arch bridge that is connected over a large gap

spread the forces out instead the bridge is restrained by tension. A regular arch bridge has abutments, which is the arched structure like the trusses of a truss bridge and they transfer the weight. Like beam bridges it has repeated arches creating pillars.

A Cable Stayed Bridge

A Suspension Bridge

The forth and final bridge is the suspension and cable stayed bridge which instead of spreading the forces of the bridge. Suspension bridges are suspended from cables and towers the cables hang from towers that are attached to caissons or cofferdams. The caissons or cofferdams are implanted deep into the floor of a lake or river. A cable stayed bridge like suspension bridges, are held up by cables. However, in a cable-stayed bridge, less cable is required and the towers holding the cables are proportionately higher.

Programming

   Programing is important to understand how a robot works, without it it is just wires and movable pieces of metal. To program is to provide a computer or machine how to perform an automatic task with coded instructions. Programming we used in class was not as complex as making them with algorithms on the computer but was still complex. The programming we did in class was that each sensor or moving part was wired into a port into the computer. You then chose a specific action and how it would perform it ( Ex. Move two wheels, forward) and then what would follow it until you reached your goal. Another thing we did was that we created individual programs for the robot to do if it sensed specific things and then added them to the bigger program overall ( Ex. sensing the color green and playing a sound. sensing the color blue and go backwards).

What programming looks like coded

Programming is used to make computers and calculators and other things we use every day, ways programming has been integrated into technology is that it is used in many things in the media. People program websites and online widgets using JavaScript and other programming systems. Programing is used to create the worlds and AI of things in video games and programming is also used in hacking which is  accessing a computers original program and changing it to access and steal data, send viruses, or take control of the computer allowing you to change things and is illegal , unless hired to hack a computer to check it's security.

To conclude programming is creating a code that machines follow and is used mainly in robots and computers but is used in the media and can be exploited to control private computers. 

Robotics

   As we integrate into a new age of technology we have the power to create what was once a dream of a far away future, robots. Although the robots we have today don't act as our personal helper to do are every wish they instead  work behind the scenes performing tasks we seem to oversee. So what is a robot and how is it used today? Surprisingly to some people robots are not machine like humans here to take over the Earth but are machines that can carry out complex series of actions autimatically   and most can be programmed through computers. Taking this definition into account robots vary from    things in our household like an automatic vacuum cleaner to a complex machine that manufactures goods on a conveyer belt. These robots may perform tasks that are easy but they change our way of life drastically and are a giant leap in science.

Robot sorting goods sung complex machinery to perform an easy task

     A robot, although a machine, has parts that mirror our body and the way it works. There is normally a metal structure that surrounds the robot to protect the machine and wires to get damaged like a layer of skin. A system of wires that connect the moving and sensing parts of the robot like the nervous system, which is connected to the brain or the computer which sends the signals in the wires to the moving parts and sensors according to the program . Sensors that see things like color or objects and sense things like touch which then send signal back to the computer which sends out the order for the  next part of the program resamples our five senses. It also has pieces that makes up the infrastructure like bones that move. In the example of our robot it mirrored the actions of a puppy but instead of being living it is made up of wires and moving parts. Another example of a robot mirroring the actions of humans  is robotic prostetics and even surgeries done by robot hands by specialists in other countries

    To conclude robots are machines that are programed to perform tasks and they can even mirror the way our body works, this leap in technology affects medicine, manufacture of goods, and the way we live.

My EV3 MIndstorm Robot: Puppy

We were assigned to choose between 4 different programs an robots to build, our Lego robot was the Puppy, the Puppy included a touch sensor, color sensor, and wheels to move and reacted to certain colors. The puppy robot was constructed over a series of three class periods and was successfully programmed to react to  colors ( Green, Blue, Red, Yellow), change the display on the screen, lift up legs, bounce and turn, lifting up hind leg, and play sounds ( eating, barking, and growling).



This is the final product of our robot

Our robot would sense a color and it would play an eating sound and a face on the screen, and a mechanic on its back would trigger a motion sensor when it was touched representing "petting". If you "fed" and "pet " the robot enough it would bounce  up and down, play a barking sound, and display hearts in its eyes. If you "petted" it too much it would play a growl sound and crouch. Feeding it too much will make it lift u its back left leg to symbolize peeing . Some things included on this robot were two mechanical legs in the back and two non mechanical in the front. A head the moves up and down and ears as well as a tail made out of a ball and cup.

This is a video of the robot being fed, peeing, petting, and being happy

Physics of a Catapult

Today I am going to write about the testing and creation of my rat trap catapul as well as the physics and mechanics of one.

Here is an image of a catapult if you didnt already know

First a catapult works by pulling back the catapult arm along a string, secondly you then put your ammunition in the cup or basket. The pulled back arm has potential energy or stored energy that is not used. When you let go the potential energy turns into kinetic energy or the energy of movement.when the arm is topped the ammunition is sent flying because of Newton's second law, an object in motion stays in motion unless acted on by a force, so the ball flys away because of inertia.

First off I built my rat trap by taking out the staples and the zz trigger mechanism.

Secondly I then used a Popsicle stick and tapes it horizontally across the spring so it is easier to pull back

I then taped a vertical Popsicle stick which is the arm of the catapult

Then I taped a plastic spoon on top of the vertical Popsicle stick. This is the catapult basket.

I then taped two erasers together and put it at the base of the spring this acts as the stopper of the catapult.

I needed a base for my catapult so that it didn't flip upside down, I didn't have any spare wood to glue it to so I made a Popsicle stick base and glued the mouse trap to that. That is my mousetrap catapult and hopefully I don't fail miserably tommarow in class.