Hello I am new to the forum and after looking for a short time did not find what fits my needs.
I would like to build a circuit that can detect a pendulum passing by, measure the period of a pendulum, and calculate the pendulum’s length. When the length calculation is completed the circuit will display the length accurate to within one tenth of a centimeter. This will require a three digit display.
The periods of these pendulums will vary in length from 0.7 seconds to 1.5 seconds. The shaft of the pendulums as it passes by the detector portion of the circuit will vary in width from 0.5 inches to 1.5 inches. The depth of the pendulums will be about 12 inches. To better understand this, imagine a 1”x12” board swinging. I was thinking along the lines of using a photocell to detect the shaft passing the detector but I am open to other methods as long as the method does not touch the pendulum or require anything to be attached to the pendulum.
This description of a pendulum may help you if you are not familiar with the terminology. When a pendulum is displaced from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position. When released, the restoring force combined with the pendulum's mass causes it to oscillate about the equilibrium position, swinging back and forth. The time for one complete cycle, a left swing and a right swing, is called the period. A pendulum swings with a specific period which depends on its length. Therefore one period will be the time it takes for the pendulum to pass the detector two times.
Requirements:
1. All circuitry should be powered by an commonly available power soured
a. Power source can be AC, DC, or AC/DC Converter
b. The availability of either AC or DC would be beneficial
2. An On/Off button to apply power if the unit is off
3. The On/Off button will remove power if the unit is on
4. An Visual indication that power is on
5. No power off timer circuitry is required
6. A Reset up button that resets all counters and timers
7. The Reset button should stop any circuitry
8. The Reset button should not remove power
9. A Start button
10. Timing will not initiate until the pendulum passes the detector after the Start button is pressed
11. Timing will stop after a predetermined number of periods has been detected
12. A switch or button should be available to select the average of 1, 5, or 10 periods for measuring the length of a single period.
13. An audible indication will be sounded each time the pendulum passes the detector
14. A visual indication will be displayed each time the pendulum passes the detector
If all I need is a detector and a microprocessor that I program that is fine. I would also like to see the bells and whistles on the circuit. I would like to put all this circuitry in a plastic case so the smaller the better.
Help me if you can.
M10SINV
I would like to build a circuit that can detect a pendulum passing by, measure the period of a pendulum, and calculate the pendulum’s length. When the length calculation is completed the circuit will display the length accurate to within one tenth of a centimeter. This will require a three digit display.
The periods of these pendulums will vary in length from 0.7 seconds to 1.5 seconds. The shaft of the pendulums as it passes by the detector portion of the circuit will vary in width from 0.5 inches to 1.5 inches. The depth of the pendulums will be about 12 inches. To better understand this, imagine a 1”x12” board swinging. I was thinking along the lines of using a photocell to detect the shaft passing the detector but I am open to other methods as long as the method does not touch the pendulum or require anything to be attached to the pendulum.
This description of a pendulum may help you if you are not familiar with the terminology. When a pendulum is displaced from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position. When released, the restoring force combined with the pendulum's mass causes it to oscillate about the equilibrium position, swinging back and forth. The time for one complete cycle, a left swing and a right swing, is called the period. A pendulum swings with a specific period which depends on its length. Therefore one period will be the time it takes for the pendulum to pass the detector two times.
Requirements:
1. All circuitry should be powered by an commonly available power soured
a. Power source can be AC, DC, or AC/DC Converter
b. The availability of either AC or DC would be beneficial
2. An On/Off button to apply power if the unit is off
3. The On/Off button will remove power if the unit is on
4. An Visual indication that power is on
5. No power off timer circuitry is required
6. A Reset up button that resets all counters and timers
7. The Reset button should stop any circuitry
8. The Reset button should not remove power
9. A Start button
10. Timing will not initiate until the pendulum passes the detector after the Start button is pressed
11. Timing will stop after a predetermined number of periods has been detected
12. A switch or button should be available to select the average of 1, 5, or 10 periods for measuring the length of a single period.
13. An audible indication will be sounded each time the pendulum passes the detector
14. A visual indication will be displayed each time the pendulum passes the detector
If all I need is a detector and a microprocessor that I program that is fine. I would also like to see the bells and whistles on the circuit. I would like to put all this circuitry in a plastic case so the smaller the better.
Help me if you can.
M10SINV