Design Your Own Experiments With PSLab

PSLab, with its simple and open architecture allows programmers, hobbyists to use the tool for various measurements and to develop new experiments with simple python code. One of the main target group, the PSLab is aimed at, is high-school science teachers and students, who may or may-not be familiar with the computer programming. For such users it is difficult to design or develop new experiments on their own. They may also find it difficult to fetch the data and plot required graphs, if a ready-made GUI is not available for that particular experiment. To enable such users to quickly design a simple experiment for studying various phenomena, we have developed a simple Experiment Designer GUI. This incorporates few controls, read-back elements and easy functions to select parameters and plot graphs. The screen shot of the 'Design Your Own Experiment' GUI along with the App-window is here.. Experiment Designer allows the user to define the control and read-back sequences of parameters and execute them. Features of "Design Your Own Experiment" GUI Configure Experiment : Here user can select the required channels ( manual / sweep / read-back). One can also add a derived channel for measuring some physical quantity, for example 'current'. Make Measurements : Selected channels are displayed. User can make measurements individually for each step or  can sweep in auto mode. Plot and View Plots: Enables user to plot selected parameters. Acquired plots can be selectively displayed or deleted. Save Plots: Data acquired can be save in a spreadsheet. Save Profile : Experiment profile can be saved for repeating the experiment in future. Saved profiles can be loaded from "Load Profile" tab. Example : Diode IV Characteristics Experiment For this experiment one needs the following... A variable voltage source : Needs to be swept from Voltage A to  B (say from 0V to 5V) Current Monitoring : Needs to be read for every value of Voltage Plotting and analytics :  Tools to plot the parameters and save data Schematic Circuit diagram: CH3 monitors the voltage drop across the diode. PV1 is varied in steps, and for each step the current is calculated from the difference between voltages at PV1 and CH3, and the known value of the resistor. For example for 1K resistor, current through the diode is given by I = (PV1-CH3)/1K Procedure : Step 1. Connect Fossasia PSLab to the pc. Connect the components -  Diode from CH3 to Ground and  1k resistor from PV1 to CH3 Step 2. From the terminal Run Experiments The App-window will pop-up. Click on 'Design your own Experiment' button to get the experiment designer GUI. Step 3: Select channels Sweep Channel PV1 - Sweep from 0.00V -5.00V in 200 steps Read-back Channel CH3 - for monitoring voltage across the diode Derived Channel - To measure Current. Type the equation to calculate the current,   (PV1()-CH3())/1000 Step 4. Click on 'Prepare Experiment' to get measurements screen. Click on 'Evaluate All Rows' to make the measurements. Step 5. Select the required columns and click on…

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PSLab Code Repository and Installation

PSLab  is a new addition to FOSSASIA Science Lab. This tiny pocket science lab  provides  an array of necessary equipments for doing science and engineering experiments. It can function like an oscilloscope, waveform generator, frequency counter, programmable voltage and current source and also as a data logger. The control and measurement functions are written in Python programming language. Pyqtgraph is used for plotting library. We are now working on Qt based GUI applications for various experiments. The following are the code repositories of PSLab. https://github.com/fossasia/pslab  : This repository hosts the Communication library for  PSLab. https://github.com/fossasia/pslab-apps  : This repository is for Qt based GUI programs, widgets and templates for various experiments. Installation To install PSLab on Debian based Gnu/Linux system, the following dependencies must be installed. Dependencies ============ PyQt 4.7+, PySide, or PyQt5 python 2.6, 2.7, or 3.x NumPy, Scipy pyqt4-dev-tools #for pyuic4 Pyqtgraph #Plotting library pyopengl and qt-opengl #for 3D graphics iPython-qtconsole #optional Now clone both the repositories pslab-apps and pslab . Libraries must be installed in the following order 1. pslab-apps 2. pslab To install, cd into the directories $ cd <SOURCE_DIR> and run the following (for both the repos) $ sudo make clean $ sudo make $ sudo make install Now you are ready with the PSLab software on your machine :) For the main GUI (Control panel), you can run Experiments from the terminal. $ Experiments If the device is not connected the following splash screen will be displayed. After clicking OK, you will get the control panel with menus for Experiments, Controls, Advanced Controls and Help etc. (Experiments can not be accessed unless the device is connected) The splash screen and the control panel, when PSLab is connected to the pc. From this control panel one can access controls, help files and various experiments through independent GUI's written for each experiment. You can help ------------ Please report a bug/install errors here Your suggestions to improve PSLab are welcome :) What Next: We are now working on a general purpose Experimental designer. This will allow selecting controls and channels and then generate a spread sheet. The columns from this spreadsheet can be selected and plotted.  

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