A people counter is a device used to measure the number and direction of people traversing a certain passage or entrance per unit time. The resolution of the measurement is entirely dependent on the sophistication of the technology employed. The device is often used at the entrance of a building so that the total number of visitors can be recorded. Many different technologies are used in people counter devices, such as infrared beams, computer vision, thermal imaging and pressure-sensitive mats

Infrared beams
The simplest form of counter is a single, horizontal infrared beam across an entrance which is typically linked to a small LCD display unit at the side of the doorway or can also be linked to a PC or send data via wireless links and GPRS. Such a beam counts a ‘tick’ when the beam is broken, therefore it is normal to divide the ‘ticks’ by two to get visitor numbers. Dual beam units are also available from some suppliers and can provide low cost directional flow ‘in’ and ‘out’ data. Accuracy depends highly on the width of the entrance monitored and the volume of traffic.
Horizontal Beam Counters usually require a receiver or a reflector mounted opposite the unit with a typical range up to 6 metres (20 ft), although range finding beam counters which do not require a reflector or receiver usually have a shorter range of around 2.5 metres (8 ft 2 in).
Vertical beams are somewhat more accurate than horizontal, with accuracies of over 90% possible if the beams are very carefully placed. Typically they do not give ‘in and out’ information, although some directional beams do exist.

Computer vision
Computer vision systems typically use either a closed-circuit television camera or IP camera to feed a signal into a computer or embedded device. Some computer vision systems have been embedded directly into standard IP network cameras. This allows for distributed, cost efficient and highly scalable systems where all image processing is done on the camera using the standard built in CPU. This also dramatically reduces band width requirements as only the counting data has to be sent over the Ethernet.
Accuracy varies between systems and installations as background information needs to be digitally removed from the scene in order to recognize, track and count people. This means that CCTV based counters can be vulnerable to light level changes and shadows, which can lead to inaccurate counting. Lately, robust and adaptive algorithms has been developed that can compensate for this behavior and excellent counting accuracy can today be obtained for both outdoor and indoor counting using computer vision

Main concept behind this project is to measure and display the number of persons entering in any room like seminar hall, conference room. LCD or seven segment display display placed outside the room displays this value. And when number of persons inside the room are zero, power supply inside the room can be cut using a relay interface. Second part of project serves the functionality of a door-latch opening using a password entered through keypad. As well as sending this data to a computer through serial port. This module also turn on buzzer if 3 wrong passwords are entered consequently. User can change this password anytime he/she wish using a keypad.

IDEA NOTE: This idea is open for working models and improvements. I have hardly any experience with steppor motors/worm gears, and have few tools and material to do this. (Update: It is very possible to use regular motors of particular qualities) So if you want to try it, and it works, you will be given credit in the overall design and construction. Just because I have designed this does not mean you cant try something based on this design. Every design, even patents, can be improved, its valid logic so that growth is not limited. Off the shelf solar trackers, perhaps two of them, have a good possibility in this system. There are pro’s and cons to every heliostat system, for example weather it is electronically or (blindly) steered using an electronic timing program, or senses the sunlight for steering. Some systems here on YouTube even uses a “water timing” method to steer at 15 degrees per hour.
Your input is needed on the forums where all the nuts and bolts about related things can be discussed.

The benefits of this design: Simplicity and perhaps low cost. Does not need any computer for timing. The same heliostat would work on Earth, the Moon, Mars, etc., without any new computer timing and the corresponding computer/.electronic timing program to actuate the motors to move the mirror.

Downside to the benefits: May have to be manually steered/aligned a bit at least once a day if the sensors cannot handle it. It is possible that the sensors can be turned/adjusted a bit to assist this daily alignment if need be, along with the gears.

This is basically like my previous video (please view and read the notes there), but here I show were the light sensors would be, as I described before.
For the light sensors, there is no “pots” (voltage/current potentiometers) that I was thinking of in the circuitry. Just some “comparator” or “logic” circuitry. When the (say vertical) sensor is aimed at the sun both will be “illuminated on” giving a signal as such. This signal should “shut/turn off” the motor. When one sensor of the (say vertical) sensor team is illuminated a motor will be turned on to rotate the gear so that both sensors will be illuminated and then the motor will turn off.

The sensors might be: light dependent resistors, small solar cells, photo resistors, certain color led’s. All these are currently being used elsewhere on the internet to steer “solar trackers” for solar panels. You will have to be very conscience of stray light hitting the sensors. Small flat black tubes or shadeing needs to be considerd, and the size of the openings to the sensors.

I believe a steppor type motor is necessary, and probably a worm gear (or other low ratio gear system) to increase the “fine tuning” of the the adjustments the motors will take to track the sun. A very simple method/circuit to activate the motors is only necessary I believe. No special circuitry, except that the vertical motor will need to be reversable since the sun “goes up” and then “goes down” vertically in the sky throughout the daylight hours. Note, the motors can either be directly attached to the axis of the horizontal and vertical gears, or gear/pully connected to those gears. Most likely a gear/pully – non direct drive – would be used for “fine aligning” the heliostat….specifically, it would take several pulses of the motor to amount to one minimal movement of the heliostat.

Note, this is only a basic drawing to show the functional design possibilites. There’s lots to “improvee”. For example, the vertical adjust gears would most likely be in a upright/vertical position, perhaps afixed to a metal frame. Also, where the mirror is attached leaves some ideas open, such as the gear section where the mirror is attached should be flat for better holding of the mirror.

Along with the design, all the testing and improvements are needed.

There are several good websites with good discussions about heliostats. Here is one I recently found, with a DIY heliostat and discussions I think people interested (if not for yourself, but for others you know, etc): https://www.iwilltry.org/b/projects/build-a-heliostat-for-solar-heating-and-lighting/

redrok.com has good discussions also for DIY heliostats.

Please visit this forum for solar and cnc projects – make a connection and sign up for a forum if you havent by now:

https://cerebralmeltdown.com/forum/index.php

Please see my previous videos also on heliostat for any notes I didnt place here.

I recently put “non quartz” in the title. Basically this means no electronic/computer timing method is used for this heliostat to track the sun. A quartz crystal is used to keep the accurate timing of these devices, and was/is used alot in clocks/watches and many electronic devices today. Many good heliostats actually use electronic timing, but this project is for one without timing.