Designing Definition and 577 Threads

Hello, This summer I would be interested in designing my own model rocket. I do not have a lot of aerospace/aerodynamics (read the NASA (http://www.grc.nasa.gov/WWW/k-12/airplane/)) knowledge but I do have a good grasp of math and physics. I would like to use a A or B model rocket engine and...

I would like to make some custom made extension springs out of music wire. Can anyone provide the formula's to determine the wire thickness, coil diameter and coil length to achieve a desired spring constant? The motivation is that I need some small springs in my research and it is difficult...

Homework Statement I have to design a lab to calculate the delta H value of the enthalpy change of ice to liquid water. It has to stay at 0*C Homework Equations Needs to be in lab format but possible q=n(delta H) where n is the molarity The Attempt at a Solution I know the...

Hi, I started to design a simple circuit and want to ask you what you think about it. http://img152.imageshack.us/img152/8508/circuit.th.png Basically what I have is a motor that can be turned on with a switch and can run for 5 more seconds when the switched is turned off. The coil...

hello, lately I've been thinking how to roughly design a compressed air powered car. i'd take an existing commercial car, take out its IC engine, fuel tank and all the other stuff and mount my own machine and tanks in. i want it to travel 300 km (185 miles) at speed of 90 km/h (55 mph)...

hello, i was wondering what people here would think the best design type for a potato launcher would be. I looked at catapults, ones that use compressed gas, and combustion. firstly, which would be the easiest to make?

I teach high school physics and I would like to get maximum mileage out of my Lenz's law experiment/demonstration. I am going to get the students to drop magnets down a long copper tube to calculate the magnetic force using distance, time etc and making a direct calculation using Fnet=...

Homework Statement Design a dc transmission line that can transmit 225 MW of electricity 185 km with only a 2.0% loss. The wires are to be made of aluminum and the voltage is 660 kV. 2. Homework Equations P= IV = I^2 * R R= p(L/A) Power loss = Pf - Pi Attempt at a solution I worked through...

For a school science project I am supposed to design an experimental process that utilizes the wind tunnel my school owns. I've built four small model towers out of wood - one a triangular prism, one a rectangular prism, one a cylinder, and one a pyramid - that all have the same height and base...

I'm currently making a coil assembly for a customer. The coil has the following specs: 120 VAC application 1,600 Turns 22 AWG magnet wire 12.5 ohms typically coil is in a circuit with a half sine wave rectifier and a solid state VAC controller current draw is .6 amps (72 watts)...

I wish to mathematically represent point light sources inside a structure, and figure out how much like is scattered throughout the structure. Specifically, I have lighting values of a certain amount of lux, and I need to ensure that the structure has a minimum of (certain value) lux touching...

As part of our project work we have to design a circuit using op-amps on PCB giving reasons why we used the resistors of particular value etc. any suggestions or references?

My homework problem says to construct a thermometer which could accurately measure a negative temperature. I have no idea how to do this. Any help would be very appreciated!

I need help!... Hi all, I'm new to this forum. I just joined the forum and I hope that you guys could help me out. I'm in the trading business of cookware. I'm currently studying the European standards for these items and there's a point in the standard that I don't understand at all...

I am designing a machine using a cam to generate a down force on a customers product (chew toy). The customer is wanting to try out different materials against his current production model. I was wondering if anyone could help me calculate the cam force in the veticle direction using a 110...

Hi I need a software for designing airfoil that alows changing the choard size and printing. If you know any please tell me. Btw do you know any refrence for low Reynolds number (about 50000)? I want to choose NACA7610 for my glider but I don't know exactly how it behaves at low Reynolds...

Hi this is my first post here, I am just looking for some advice on designing a F1 model car. Like what the best possible shape for a Formula 1 car could be (Less drag and other factors which may effect its speed). The model car will be propelled forward by a Co2 Canister and will be and a...

I want to design a thermistor circuit to be sampled by a microcontroller using an 8 bit ADC, with a voltage reference of 2.55V, I know the following T (ºC) R(ohms) 25 2815 40 1200 I am going to use a potential divider then use a linear approximation to measure the...

Hello every1 I hav a basic question bout Design of inverters(Voltage source inverters). Wel Actually what does designing mean? I hav to design a inverter whose output Peak voltage is 50v. The input DC voltage wil b around 55V.I'm using single phase full bridge inverter And i'll b using R...

I have taken both Analog circuits and Digital Circuits. These are the only EE courses I can take with my curriculum--I will have to self-study. If am looking to design RF and sensor circuits, where do I start? I look at a radio transmitter schematic and am dumbfounded on how the designer would...

Hello Everyone, I would like some help developing a model. I am using the Solver in Excel, but the results are giving me counter-intuitive results. I believe it is because my model is incorrect. Once I get some help perfecting the model, then I will worry about translating it for the Solver...

I want to build a porter governor to control the speed of a shaft via a varible dia double cone pulley. The speed range to be considered is b/w 250-750 rpm. I would like to know the equations involved. My textbook provides theoretical equations, I would be obliged if I could get the actual...

The problem is designing a solar water heater system to keep a 4500 gal tank of water at 140F during the day. The tank in question has the following properties: 5000gal Volume 4500gal water It loses about 1.8 degrees F/hr if not heated. I first need to figure out amount of energy...

Hi guys.. I am currently working on a research where I have totally no idea in. What are the factors i need to take into consideration if I were to design a pressure vessel?

Hi guys, Background: There are 2 relays, A and B that needs to be controlled (24V) And a signal generating device that composes of a push button and an adjustable mechanism for timing delay between the 2 signals. (this is what I want to design) Specification: I want to design a...

I am considering the idea of making a small scale wind turbine for my final year B.Tech project. I have run into a roadblock, I have to maintain the generator at a relatively constant speed. I was thinking of 2 parallel shafts one from the Turbine blades coupled via a CVT to the shaft to the...

Hi Guys, I need to design something that will isolate our DAQ (Data Acquisition Card) for a basic simulation we need to do. I was thinking about designing a mosfet switch, where the DAQ sends some voltage to the gate above the threshold voltage to turn the MOSFET on and 0 V to turn it off...

I'm a sophomore Aerospace major, and I'm also a new member to a rocket student group at my university. We are currently involved in a competition with NASA, and they have asked our group to write a Preliminary Design Review. Everything was split up, and I was left with the rocket's airframe...

I am currently in the process of designing a battery monitoring circuit. At the moment we are planning to base the circuit around the MAX4081 (bidirectional current sensor) and a microcontroller (atmega48). I am a bit concerned as to whether or not we will actually be able to get anything out of...

I want to develop a solenoid for push application. the required push is around 5kg by electromagnet. We can use a combination of permenant magnet and electromagnet to optimize the design with respect to area and power consumption. For eg. the solenoid can push a permenant magnet also...

Hi I have to design a gearbox for a drum, the drum should be brought uniformily to a speed of 7rpm in 8 seconds, I have choosed a motor of 715 rpm output, what's the gear ratio I should use in designing the gearbox? Thanks

I want to build a digital timer that will switch my geyser on and off at a preset time in order to save power. I don’t know much about PICs so I would rather try using only logic ICs. It has to have at least 3 preset ‘on-times’ and 3 ‘off-times’. Can anyone help me to get started?

i thought of a design for a toroidal engine. is there anyway i can check if it is actually possible to practically implement this design?

Hi all! Thanks in advance if you're able to help me here... It's been 20+ years since I've toyed around with circuits, and I'll admit I forgot most of what I used to know. My application is as follows: I have a gauge in my car, that reads pressure (turbocharged car application). I'd...

I am designing a go kart for my college project. I am stuck with finding out how much horsepower I need. I know the centre of gravity and the total weight. Say I set a criteria that the gokart has to accelerate at some m/s^2 from there on how can I find the horsepower. I know the tyre radius and...

Homework Statement A 4-bit arithmetic and logic unit (ALU) is to be designed for a 4-bit microprocessor. The ALU has two 4-bit wide inputs, labelled ii and i2 and a 4-bit output labelled out. In addition there is a carry-out bit. Design the ALU so that it implements the following functions...

I am trying to build a system to activate a servo at a unspecified point in time when a machine and remote looses their signal between another. When the signal is lost between the two, the new system must activate a servo. We are using radio transmitters, but I can't figure out how to tackle...

I am trying to build a system to activate a servo at a unspecified point in time when a machine and remote looses their signal between another. When the signal is lost between the two, the new system must activate a servo. We are using radio transmitters, but I can't figure out how to tackle...

Hi All, I am pretty new to COMSOL. I want design model of a sensor with four electrode. This sensor mainly based on impedance spectroscopy principle. The model should measure the distance and thickness of the obstacle due to change in capacitive impedance of electrostatic field between the...

I am trying to build a system to activate a servo at a unspecified point in time when a machine and remote looses their signal between another. When the signal is lost between the two, the new system must activate a servo. We are using radio transmitters, but I can't figure out how to tackle...

Hi Any body who can send me the link to a free low power sinewave transformer designing software and also of some free ebook on this subject.

hi Is it necessary for a hardware electronics design engineer to know hitech math and physics to do his daily work. Can he survive without them?

Homework Statement I'm supposed to design a practical about factors that affect flight. I've decided to use Bernoulli's Principle to help me do this experiment. So I am planning to alter the thickness of the wing (independent variable) see its effect on the horizontal displacement (dependent...

Hi, I am trying to design a few low power (I ~ nanoamps, V ~ volts) test devices. I can't seem to find books on test equipment design anyplace. Anyone got a favorite text or anything? Sean

can you design a series capacitor and battery set up where one plate of a capacitor in series has an unequal amount of charge ? Feel free to use different dielectrics or any other devices, but the set up must be in series.

I need help writing the code for a simple lottery machine. Here are the key points. Ask the user to choose 3 numbers between 1 and 20. Randomly generate 3 winning numbers that are between 1 and 20. Determine how many, if any, of the users numbers match the winning numbers. If (hypothetically)...

I'm trying to determine the feasibility of a project, but have not yet taken fluid dynamics (next quarter). I'm trying to figure out how much power could be produced with a CO2 powered turbine. The turbine will be activated for only a few seconds at a time, with speeds under power ranging...

Hi, As you know , PCB design tools have manuals accompanying them ,but there are points in designing that a PCB designer earns by long time experiment.Now,are there any places on the web telling us these special points or tricks?

HI, I'm constructing a 2D nozzle for fluid testing. I have made my nozzle X5 larger and taken a 1/8" slice. Now I'm having trouble designing the 2d nozzle so that the exiting air will have a velocity of 3ft/s. I must maintain an Re number of 1000 as well. My problem lies in that fact that. I...

Hi, Im currently doing an assignment where i have to design a water reticulating system for a small suburb. I have planned out all my distribution mains and my reticulation mains and services I also have the water demand(Q) for the houses using the Australian Standards for plumbing and...