﻿ Remote Experiments - Remote-Lab GymKT
NOTICE:
We disagree with the exclusion of Newton's laws, Ohm's law and the law of energy conservation from the physics curriculum of elementary schools in the Czech Republic!

## Remote experiments at GymKT

### Experiments Controlled by USB Board K8055

#### Temperature Dependence of Resistance of Metals and Semiconductors

##### Experiment VILI („Vilík“) – V.I.L.-I – "Vzdálená Internetová Laboratoř I."

The function is based on measuring the resistance of two basic electronic components - sensors and a platinum thermistor with a negative characteristic - at different temperatures. To heat (or cool) the two components, a Peltier is used whose output is controlled by pulse modulation. The resistance of both parts is sensed by an operational amplifier and a pair of AD converters are converted to digital form. Coupled sensor components are complemented by a digital thermometer. The current temperature reading on the thermometer display - in real task is read by USB webcam.

Operating systems such as changing the polarity of the Peltier switching assets under / stand-by mode is provided by the amplification of digital signals from control computer. Communication devices and PC via USB. The above-mentioned management apparatus is used Universal USB Experimental Board K8055.

#### Determination of the Earth's magnetic field

##### Experiment NICoL („Nikolka“) – N.I.Co.L. – "Next Internet Controlled Lab"

The classical method of measuring the horizontal component of the Earth's magnetic field is the tangent compass method. At the beginning of the measurement, the coil is adjusted so that its plane coincides with the magnetic meridian plane and thus with the direction of the needle. The magnetic field is given by the vector sum of the Earth's magnetic field and the magnetic field generated by the coil.

The experiment is based on a comparison of the Earth's magnetic induction and the artificial induction induced by the so-called Helmholtz coils. Knowing the artificial magnetism (or current coils) and the vector sum of both magn. induction is the observed value of the horizontal component of the Earth's magnetic field at a given location.

Due to the field coil, the magnetic field vector is perpendicular to the horizontal component of the earth's magnetic field, the magnetic needle is deflected from its initial position by an angle φ and reach a new equilibrium corresponding to the direction of total magnetic induction. Angle odklomu needle from its original direction is subtracted from the webcam.

#### V-A Charakteristics of LED (Determination of Planck's constant)

##### Experiment CEcIL („Cecilka“) – C.E.c I.L. – "Čtvrtý Experiment (c) Internetová Laboratoř"

The task is to compare the technical characteristics (in the pass-through direction) of red, yellow, green, blue, and white LEDs in volt amperes. The acquisition threshold voltage can be used to determine the width of the bandgap semiconductors used and the wavelength of the emitted light. The measuring principle of this part is based on the standard method of measuring the V-A characteristic of the electronic element. We're changing the voltage on the measured element (here LED) by a variable power supply. Subtract the size of the electric current to the amperemeter, which is connected in the circuit.

Regulated power supply and measuring instruments replace the measuring USB card K8055 in case of this remote experiment CEcIL. The digital-to-analog output is current-amplified and serves as a regulated power supply. A pair of analog-to-digital inputs are used as a pair of voltmeters. One measures the voltage across the LED, the other measures the voltage across the ballast resistor. The current is determined by knowing the voltage across the resistor. Five digital outputs of the K8055 board are then used to select one of five LEDs to be measured.

#### Basic features of the bipolar transistor

##### Experiment PaVEL („Pavlík“) – Pa.V.E.L. – "Pátý Vzdálený Experiment Laboratoře"

The experiment is designed to measure the output and transfer characteristics of the bipolar transistor – in particular, to determine the current gain of the transistor. In the future, the experiment will be extended to measure the input characteristics of the transistor. The 2N3055 bipolar transistor was selected for this task. It is often used as a power transistor in the output stages of various amplifiers. Therefore the transistor and its characteristics are well documented. The obtained experimental values can be compared well with the values of the catalog or datasheet.

The transistor is connected to the K8055 board. The base voltage of the transistor is set by the first DA-converter of the USB board K8055. The output of the second DA-converter is used as a variable source voltage for the collector circuit. Both DA outputs of the USB board K8055 are current-strengthened. Conversely, a pair of input AD converters are used to load electrical quantities. They are used as ammeters to determine the magnitude of flowing currents and as voltmeters to determine the voltage between the collector and emitter.

#### Classic bulb V-A characteristic

##### Experiment VeLMA („Velma“) – Ve.L.M.A. – "Velmi Levná Měřicí Aparatura"

The purpose of the experiment is to show the true shape of the current-voltage characteristics for such common devices as light bulbs. Measuring the current-voltage characteristics of the bulb is the student's first encounter with so-called nonlinear loads. At the same time, we can demonstrate the thermal dependence of the electrical resistance of metals, in particular by comparing the resistance of the cold and the hot bulb. The measuring principle of this exercise is based on the procedure of changing a variable supply voltage to the measuring element (here bulb 2.2 V/0.18 A), and we deduct the magnitude of the electric current on the amperemeter connected in the circuit.

The role is another in a series of jobs are entirely developed and built at our cost. The control of the experiment is again realized using the USB board K8055 with the control application K8055-MARIE. In this case, even the role uses free capacity control board K8055 from the role of NICoL and so is realized directly on the apparatus of this experiment. This helped us not only to create a new task with minimal costs (about 200 CZK), but mainly we created two independently controllable tasks on a single board K8055. It is still unique in the world!

#### Load characteristic of the source

##### Experiment ZaCHaRIAS („Zachariáš“) – Za.Cha.R.I.A.S. – "Zatěžovací CHarakteristika, Remote Internet Apparatus System"

A remote experiment allows you to measure the load characteristics of two commonly used electrochemical sources – alkaline and zinc chloride batteries. An incrementally increasing current is drawn from both electrically charged batteries. Each value of the drawn current is measured simultaneously with the value of the corresponding terminal voltage. After plotting the pairs of current-voltage values on the graph, we get the dependence of the terminal voltage on the drawn current – the so-called load characteristic of the source. The shape of this dependence is influenced by the internal structure of the battery cells, which can be described electrically by the basic parameters of the source – electromotor voltage, internal resistance (or short-circuit current).

The role was developed by our students in the competition: Technical Olympics of the Pilsen Region. The measurement of the task is again based on the proven K8055 USB board, but a new method of remote communication is used for control. This method is based on our original K8055-MARIE application (version 2), but uses new techniques. This has ensured backward compatibility with the original control, but with significant acceleration and increased remote control efficiency of the connected experiment. Gradually, all other tasks will be transferred, and after successful testing, this version will be released to other developers as other versions of the K8055-MARIE.

#### Solar cell load characteristics

##### Experiment DEVIL („Ďáblík“) – D.E.V.I.L. – "Desátý Experiment Vzdálené Internetové Laboratoře"

The remote experiment makes it possible to measure the load characteristic of the solar cell. This standard characteristic, which provides basic information about the operation of a photovoltaic cell as a source of electricity, is formed by a graph of the dependence of the output voltage and output power on the consumed current. Thanks to this characteristic, it is also possible to obtain the so-called fill factor and the efficiency of the solar cell used.

Although we are currently developing our new tasks using a combination of Arduino + Ethernet Shield module, this task was developed on the K8055 control board platform together with our ISES-ZOMBIE extension, which allows ISES measurement modules to be connected to the K8055 board. The K8055-MARIE application is used for remote control. The task is to show that there is no old (K8055 board) and new (Arduino) way to create remote tasks, but that these are our two completely independent ways.

### Experiments Controlled by iSES Web Control

#### Oscillations on the spring (forced & damped oscillations)

##### Experiment IRMA („Irma“) – I.R.M.A. – "ISES - Remote Managed Apparatus"

The measuring principle of this task is based on a standard measuring procedure. A spring oscillator consisting of a spring (stiffness k) and a weight (mass m) is deflected from its equilibrium position. To study damped oscillations, it is enough to "swing" the system, then stop the excitation and monitor its own oscillation. You can determine the damping coefficient δ from the time record of the instantaneous displacement of the quasi-motion damped oscillation. In case we study the dependence of the amplitude on the excitation frequency (forced oscillation), we follow the course of the instantaneous deflection for various excitation frequencies.

The coil is powered by a PC controllable AC power supply for needs change excitation frequency using a computer. Control signals for the power supply, as well as a load for instantaneous deflection of the oscillator, are controlled by the ISES experimental set. This system has several input and output ports that can be connected to various experimental modules – voltmeter, ammeter, strain gauge… etc. The experimental system is completed by ISES software kit ISES WEB Control, created for the use of remote web management tasks.

The creation of this experiment was supported by the European Regional Development Fund – CZ.1.14/2.4.00/34.03174, Equipment for the Improvement of Science and Technology Education.

### Experiments Controlled by the Arduino + Ethernet Shield

#### Robotic arm Velleman KSR-10 remote control

##### Experiment RAMBO („Rambík“) – R.A.M.B.O. – "Remote Arduino - Motivational Baby Only"

This experiment gives you an opportunity to learn the basic principle of remote control. Whether you can imagine that you are just controlling the robot research on the surface of Mars, or rescue manipulator in a contaminated area wrecked nuclear submarine somewhere deep under the sea level, the basic principles are the same. The field of view of the camera used does not allow spatial vision. The resolution of the camera is low. The remote robot reacts with a delay. Our robot simulator should show all this.

The Velleman KSR-10 robotic arm has been significantly modified for the purposes of our remote experiment. End limit switches were added. The batteries were replaced by a power source. The manual control panel was completed with electronics for control using the K8055 USB board and later the Arduino UNO module.

#### Study of diffraction phenomena (Diffraction on a grating)

##### Experiment DiANE („Diana“) – Di.A.N.E. – "Diffraction - Arduino Next Experiment"

The experiment is not public yet!

We still have a lot of work to do:
• We are currently testing the security of the remote control.
• We are preparing the experiment for 24-hour operation.

#### Radiation Absorption in Materials

##### Experiment AbRaHaM („Abrahám“) – Ab.Ra.Ha.M. – "Absorption of Radiation in Habitual Materials"

The experiment is not public yet!

We still have a lot of work to do:
• We are currently testing the security of the remote control.
• We are preparing the experiment for 24-hour operation.
• We are writing texts for websites (Apparatus description, Work task).

Theory  Run Experiment

#### Weather Station

##### Experiment GENIE („Džin“) – G.E.N.I.E. – "General Example of a New Internet Experiments"

The experiment was created primarily as an inspiration for other fans! We want to use it to present our concept of building remote experiments, which is now based on the Arduino module with Ethernet Shield connected. This task is also atypical in that the control code was developed using the mBlock development environment, for which we wrote a special extension and which is otherwise used to teach the basics of algorithms to small children. We want to show that building remote experiments is now really easy. So don't make us angry anymore and build a remote experiment too! (How-to article coming soon)

### And something for the other "bastliers" - developers

#### Management Application for Remote Internet Experiments with K8055

##### K8055-MARIE („Maruška“) – K8055-M.A.R.I.E. – "Management Application for Remote Internet Experiments"

K8055-MARIE is a server application that allows remote (Internet) control of the Velleman K8055 board. This program runs on a computer connected to the K8055 board and uses the website for remote control.

K8055-MARIE allows full control of the experimental board – setting of analog and digital outputs, reading of analog and digital inputs, setting of counter parameters.

You can read more in the link FOR DEVELOPERS.