fig1 is a block diagram illustrating the control structure of a system controller 10 of the invention . electrical power is supplied to the system controller 10 by a power supply 12 that may be of an ac or dc type and may incorporate a battery backup device . input - output devices 14 are connected to the system controller 10 and include one or more control centers 26 , which is depicted in fig2 and may include a modem or other communication device to connect the system controller 10 to telephone systems and internet connections , a keyboard for entry of data or any other similar device . unlocking devices 16 are under the direction of the system controller through control centers 26 . an unlocking device 16 might comprise , an electromagnetic , solenoid operated or motor driven release closing mechanism . an alarm status output 18 is provided by the system controller 10 which may be connected to audio devices , visual devices , rf devices , telephonic devices or direct cable devices . one or more memory devices 20 are connected with system controller 10 for storage and retrieval of data utilized by the bicycle rental and security system . such memory devices 20 may be comprised of any one or more types of volatile and non - volatile memory , including , ram , rom , flash ram , eprom , eeprom , magnetic tapes , floppy disks , hard disk drives and optical storage devices , such as , cdrom , cd - r , cd - rw and dvd . an alarm status input 22 is provided for input from one or more devices , which may comprise , electrically conductive material to complete a circuit , fiber optic material to conduct light , vibration sensors , motion sensors or the like . and an output 24 is provided by system controller 10 , which may be connected to audio , video , or hard copy printing devices to indicate the current status or report recorded data from the bicycle rental and security system . fig2 is a plan view showing a control center 26 connected to a security rack 28 , to which is secured a rental bicycle 30 by locking apparatus 32 ; control center 26 communicates with system controller 10 and rack 28 . incorporated within control center 26 is a card reader 34 which enables the control center 26 to accept and read cards , such as , credit cards , debit cards , pre paid rental cards and the like . information read from a card by card reader 34 is transmitted by control center 26 to system controller 10 . a display screen 36 may also be incorporated within control center 26 to provide display information , such as rental bicycle 30 availability information and customer record , credit and account information communicated from system controller 10 . the display screen 36 of control center 26 may be touch sensitive so that input and selections may be made by tactile contact with the display screen , or a separate keypad 38 may be provided . fig3 is a illustration of a fastening module 40 formed with a mounting bore 42 through which fastening module 40 is mounted to a segment of the frame of rental bicycle 30 . also formed within fastening module 40 is a locking bore 44 ; and one or more first contacts 46 are arranged upon or formed in fastening module 40 . contained within fastening module 40 is an article identification means and mechanical shock sensor which are incorporated within a semiconductor circuit that is programmed with information which uniquely identifies the rental article to which it is attached , and programmed with a protocol for bi - directional communication with the control center 26 . the semi conductor circuit contained within fastening module 40 is electrically connected to one or more first contacts 46 . the shock sensor contained within fastening module 40 and incorporated within the semi conductor circuit , is of any known design , such as a piezio electric film , mercury sensor or a simple resilient spring mounted force sensitive switch which is mechanically maintained in its deflected position in the event of a mechanical force sufficient to deflect the resilient spring and open or close the switch . fig4 illustrates an enlarged back side view of the locking apparatus 32 which incorporates u - shaped member 48 and slideable locking pin 50 , wherein the slideable locking pin 50 has a retracted and an extended position . slideable locking pin 50 is located within unshaped member 48 , such that when slideable locking pin 50 is in its retracted position , a fastening module 40 may be placed within u - shaped member 48 . upon placing a fastening module 40 , of a rental bicycle 30 , within u - shaped member 48 , slideable locking pin 50 may be shifted to its extended position , whereby locking bore 44 is engaged by slideable locking pin 50 securing rental bicycle 30 to security rack 28 . disposed within each u - shaped member 48 of locking apparatus 32 are one or more second contacts 52 , which are electrically connected to the control center 26 , and which correspond to the one or more first contacts 46 of fastening module 40 . first contacts 46 and second contacts 52 are caused to come into alignment and electrical contact , when locking bore 44 is engaged by slideable locking pin 50 , thereby allowing bi - directional communication between the semi conductor circuit of fastening module 40 and the control center 26 thus communicating the identification of rental bicycle 30 and the status of the shock sensor to the system controller 10 through control center 26 . the system controller 10 is therefore able to perceive the location of each rental bicycle 30 when secured to a security rack 28 and whether the rental bicycle 30 has sustained an impact during its most recent rental period , and when it is removed from a security rack 28 . also illustrated in fig4 is an alarm cable 54 , that may be provided for added security , containing electrically conductive material , such as disclosed in u . s . pat . no . 4 , 920 , 334 to devolpi , that is connected to security rack 28 and may be woven through the wheels of rental bicycle 30 so that any unauthorized loss in the electrical continuity of alarm cable 54 is perceived by system controller 10 , through alarm status input 22 , to indicate possible theft of rental bicycle 30 . in fig5 the interior components of the locking apparatus 32 are illustrated . slideable locking pin 50 , formed with a shoulder 56 about its circumference , passes through an aperture 58 and is capable of movement along its longitudinal axis from a retracted to an extended position . a key 60 is provided within locking apparatus 32 which is connected to an unlocking device 16 , such as a solenoid , whereby operation of unlocking device 16 between its locked and unlocked position will cause key 60 to engage and disengage shoulder 56 when locking pin 50 is in its extended position , and thereby selectively secure locking pin 50 from movement along its longitudinal axis . fig6 illustrates an instance in which a customer owned bicycle 62 , without a fastening module 40 , is secured to security rack 28 with locking pin 50 secured in its extended position . in operation as illustrated , a security only service may be provided using the same security rack 28 as utilized by the rental bicycles 30 , since the system controller 10 can maintain location , customer and payment information in the absence of a fastening module 40 , and the customer owned bicycle 62 may be secured with alarm cable 54 , and by its frame with locking apparatus 32 in the absence of a fastening module 40 . although the detailed description of the preferred embodiments is directed toward illustrating the above described embodiments , the present invention is not limited to such embodiments , as variations and modifications may be made without departing from the scope of the present invention as claimed herein .