2. DESIGN REQUIREMENTS

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1 2. DESIGN REQUIREMENTS The Smart Lock Security system will give the user the ability to control his or her door lock from the convenience of texting from the user s cell phone. The device can be controlled as long as the user has adequate cell service to send a text message. In addition to controlling the lock with a text message, the device will also have a keypad entry on site, forced entry sensing, and a way to change pin numbers and give or remove unlocking capabilities to other cell numbers. This document contains all technical and practical design constraints. 2.1 Technical Design Constraints For Smart Lock Security to work properly and efficiently, there are certain technical constraints that must be met. These criteria can be found in Table 2.1. Name Wireless Communication Power Supply Alternative Communication Display Forced Entry Detection Table 2.1 Technical Design Constraints Description The device must be able to communicate with the user via Short Message Service (SMS), allowing the user to unlock and to notify the user if the door has been locked or unlocked. The Smart Lock Security system must be powered by a 120VAC source. A backup battery with a current range of 0.75A - 1.5A is required to power the device in the case of a power outage. The device must provide an additional method of access and system configuration at the physical location of the device. The LCD screen must display the correct information to the user. Some of the required information will be a menu with multiple options and further instructions based on user s decisions. The device must be able to detect unauthorized entry when the solenoid is in the lock position Communication The device must be able to allow for the user to unlock the door through SMS. If the user does not have access to their cell phone, a keypad will be located on the outside wall of the secured location. A keypad also allows for friends, family, or approved personnel to gain access to the secured area. If someone who is unwelcome acquires knowledge of the code, the owner will have the ability to change the code (discussed in 2.1.4) Power Supply The device will use 120VAC source. The source must then be converted to 12VDC to control the electronic components. The backup battery must be able to supply at least 12VDC for operation when the 120VAC supply is non-operational. The current needed for the device will range from amps. The backup battery must be capable of powering the Smart Lock Security system for 24 continuous hours.

2 2.1.3 Alternative Communication Access must be possible from both the interior and exterior of the door the device manages. To facilitate this, the Smart Lock Security device must have two keypads as part of the system. One will be located externally and the other internally. The internal keypad must also function as a means for user input during system configuration. This allows for users to add and remove telephone numbers or alter additional settings Display The Smart Lock Security device must be set up for easy user interaction. It must display whether the device is locked or unlocked. Also, the LCD screen must display a helpful menu. This design component will work in conjunction with the internal keypad (2.1.3) and must be located on the internal side of the door. The combined components must allow for system configuration by the user Forced Entry Detection The device must be able to detect forced entry when someone is trying to break in. The Smart Lock Security device should also be able to send this information through SMS to the user s phone. 2.2 Practical Design Constraints Similar to the device needing to meet certain technical design constraints, it must also meet practical design constraints. These practical requirements can be found in Table 2.2. Table 2.2 Practical Design Constraints Type Name Description Economic Price The Smart Lock Security device is expected to be $ Manufacturability Size The device must have ten core components to allow for easy interaction with the device. Sustainability Reliability The system is wired directly into the customer s electrical system and is therefore as reliable as the power supply. In case of power outage, the system can be powered from the backup power supply for at least a 24 hour period. Social Compatibility The Smart Lock Security system must be compatible with most door frames (residential, commercial, and industrial). Health & Safety Safety The system will notify the homeowner via SMS if a forced entry is attempted. The user will also be able to secure area with cell phone via SMS.

3 2.2.1 Economic The Smart Lock Security device is expected to be roughly $250. One of its competitors, Goji Smart Lock, can currently be pre-ordered for $245 [1]. Another competitor, August, has similar features and is $199 [2]. Both products are powered by batteries, where the Smart Lock directly ties into the owner s electrical system [1][2]. Because of this, the Smart Lock Security device will be relatively the same as the most similar competitor costs, and will have an additional feature, forced entry sensing Manufacturability The Smart Lock Security device has ten core components that are important in the manufacturing process, three of which are visible and usable by the owner. The components are the external keypad, the internal keypad, the LCD display, the processor, the GSM module, the DC linear solenoid bolt, a directed magnetic switch, a power supply, back-up battery, and a PCB to for remaining components to help control functionality. One of the visible components, the external keypad, must be placed on the outside of the secured area in order for the user to gain on site access. There must be an indoor station that contains the LCD display and the internal keypad that will allow the user to select options from a menu. The largest external area is expected to be less than or equal to 3in. by 6in. as that area should be capable of accommodating all three user visible components. The device is predicted to incorporate an Atmel processor due to availability in prototyping frameworks. In conjunction with the processor a GSM module will be used for wireless communication between the device and the user s cell phone. The locking mechanism of the device will use a DC linear solenoid lock. This will ensure the door will be securely locked. Another component of the device will be a magnetic contact switch that will be used for forced entry sensing. The remaining components are the PCB, power supply, and backup battery, all of which will be located inside of the homeowners wall at the location of the other components of the system Sustainability The Smart Lock must be directly wired to the owner s electrical system and is therefore as reliable as the electricity provided to the home. Power outages are generally not frequent, but in case of outage, the Smart Lock must have a backup battery. For further details on the battery, refer back to section The device must be able to restart without error from a total loss of power Social The Smart Lock Security system will be compatible with any cell phone that has the ability to send a text message. The system will also work with most doors and doorways.

4 2.2.5 Health and Safety With the Smart Lock Security system, homeowners will be able to secure their homes via SMS text. Similarly, the system can be used in commercial and industrial settings in which case the user can verify that the necessary areas are properly secured. The Smart Lock Security system will also include a keypad entry that will allow users to create a pin. This pin number can be provided to authorized people in order for them gain access into the secured home or area. The Smart Lock Security system will also have an emergency backup battery that will allow the system to still operate during power outages. This will ensure that users are not locked in or out of the areas they wish to secure.

5 References: [1] Features. August, Web. 12 Sept [2] Goji FAQ. Goji, Web, 10 Sept