THE SCIENCE THE BAYBOTS WHITEBOARDED
During the year The Baybots received a number of lessons presented on the Whiteboard of general and specific scientific interest. Here is a summary of those lessons.
COMPUTER PROGRAMMING: IF THEN / IF NOT THEN
All of the Baybots were taught the principal behind Robot “Line Following” during their very first meeting. The Robot uses a LIGHT SENSOR to read the brightness of the mat beneath it. In this way the Robot is TESTING a CONDITION.
The LIGHT SENSOR READINGS are fed into a SWITCH inside of a LOOP. If the brightness is greater than 50pct it means the ROBOT is more on the white side of the edge of the black line. So the Robot drives a little to its left to stay on the on the edge of the black line. If the brightness is less than 50pct it meanse the ROBOT is more on the black side of the edge of the black line, so the Robot drives a little to its right to stay on the edge of the black line.
In other words IF greater than 50pct, THEN steer left.
IF NOT greater than 50 pct THEN steer right.
The example given for this principal was IF weekday THEN get up and go to school
IF not THEN stay in bed
MECHANICS: THE SCISSOR ARM
We wanted a really long arm to deliver Bacteria to the Sink. Because the Base has a 16 inch height restriction, if we wanted a really long arm to reach the sink, we would need something that folded up. A Scissor Arms is good for this job because you can getting a lot of movement out of a small space with a Scissor Arm. MAN-LIFTS in the real world use Scissor Arms for this reason.
PHYSICS: THE LEVER
It turns our that the The Scissor Arm that shoots the bacteria in SINK is made up out of LEVERS. A Lever is a kind of SIMPLE MACHINE – other Simple Machines are ramps, screws and pulleys.
The parts of a LEVER are the LEVER ARM and the FULCRUM.
These parts accept FORCE to move a LOAD.
There are 3 types of levers.
Type 1 – like a playground See Saw or the Arms in our Scissor Arm – FORCE is applied to one end of the LEVER ARM the FULCRUM is in the middle and the LOAD is at the other end.
Type 2 - like a Wheelbarrow - FORCE is applied at one end of the LEVER ARM and the LOAD is in the middle and the FULCRUM is at the other end.
Type 3 – like a Fishing Pole - FORCE is applied in the middle of the LEVER ARM, the FULCRUM is at one end and the LOAD is at the other.
The Baybots SCISSOR ARM actually uses a Type 3 LEVER to extend all of the Type 1 LEVERS that make up the Arm.
TRIGINOMETRY:RAISING THE SCISSOR ARM
We started by asking is it harder to lift the Scissor Arm when it is first going up, or when it is near the top.
We saw the that the Scissor Arm is always going “up and in”, “up and in”, “up and in” through a curving movment towards the top. We drew a diagram that showed the “up and in” movements the Scissor Arm would make as it grew.
Common Sense and the Diagram showed us that it must be harder to lift the Scissor Arm when it is first going up because that movement is more “up” and less “in”. Near the top when the Scissor Arm is nearly fully extended the Scissor Arm is going much more of an “in” direction and a lot less “up”. Overall, as the Scissor Arm expanded up the “ups” were getting shorter and the “ins” longer.
It turns out that we were really talking about TRIGONOMETRY when we drew that diagram. “Up” and “In” have their own names in TRIGONOMETRY and the way that “Up” and “In” relate to each other in TRIGONOMETRY to confirms what we had concluded with our Common Sense.
The Diagram broke the movement of the Scissor Arm up into TRIANGLES. It turns out that these were what are called RIGHT ANGLE TRIANGLES and what we were calling the “Up” side was actually called the ADJACENT side of the TRIANGLE in TRIGONOMETRY and what we were calling the “In” side was actually called the OPPOSITE side of the TRIANGLE in TRINGONOMETRY.
Then we learned that the relationship of these two sides to each other, OPPOSITE to ADJACENT, had a name all its own - The TANGENT - which is equal to the OPPOSITE side divided by the ADJACENT side. The TANGENT is an exact way of measuring what we were calling “a lot up and a little in” “same up and sa,e in” “a little up and a lot in” etc.
Sure enough, when we looked up the FORMULA for how much force is necessary to lift a Scissor Arm and anything it was carrying, TANGENT was right in the middle of it.
FORCE = Weight of the Scissor Arms + Weight of what they are carrying / 2 x the TANGENT
Now we know why TANGET is central to this calculation.
CHEMISTRY and PHSYIOLOGY: NERVE GAS
We started studying Celery because we heard early on that it was the most contaminated vegetable. Who would have thought that? Turns out that this is because of the fact that it has no skin, like an apple, is extremely fragrant, like a Rose - so bugs love it - and sucks up pesticides from the ground like a big straw.
We ended up learning a lot more than we would have liked about Nerve Gas.
The worst and most dangerous pesticide that is used on Celery is a family of chemicals called Organophosphates. An Organophosphate is the general name for “Esters” of “Phosphoric Acid” Phosphoric Acid is a chemical that is used to flavor Coca Cola, or to remove rust! An “Ester” is a general term for another chemical made a certain way from an acid.
Organophosphate insecticides were developed after German scientists in 1932 first noticed that human exposure to thse kinds of chemicals created a choking sensation and dimmed vision. At the same time that Organophospahtes were being developed as insecticides, they were also developed as a Nerve Gas for use as a weapon. Infamously, the first of these were known as TABUN and SARIN.
We leared that the NERVES in the body are made up of cells called NEURONS. The points where these connect to each other, and where they connect to MUSCLE CELLS, are called SYNAPSES. When a NUERON tells a MUSCLE CELL to CONTRACT – which is necessary for movement of any muscle, including the muscles that control your lungs, and Electrical Impulse is transmitted across the SYNAPSE. (There may be as many as 500 Trillion Synapses in your body).
The Electrical Impulse is transmitted by a Chemical, a NEUROTRANSMITTER, called ACETYLCHOLINE that is realeased from one NUERON across the SYNAPSE, comes in contact with the next NUERON, and causes it in turn to generate an Electrical Impulse.
Usually, the ACETYLCHOLINE is instantly broken down by another substance, and Enzyme called ACETYLCHOLINESTERASE. (Each molecule of ACETYLCHOLINESTERASE degrades about 25000 molecules of ACETYLCHOLINE per second).
An ORGANOPHOSPHATE disrupts this process by binding itself with the ACETYLCHOLINESTERASE. This means that the ACETYLCHOLINE is not broken down which in turn means that the muscle it is stimulating cannont relax. The result is constant contraction of the muscle.
In INSECTS, an ORGANOPHOSPHATE chemical causes death by exhaustion as the insect’s muscles continually contract. In HUMANS, ORGANOPHOSPAHTE Never Agents cause death by aphysixiation as the lung muscles are unable to function normally.