Smart memory alloy control

1. A method for improving performance and life of a shape memory alloy material adapted to contract when heated to a critical temperature; the method including the following steps:

(i) measuring ambient temperature before activation;

(ii) measuring voltage applied to the material and/or current flowing in the material;

(iii) calculating power and/or energy required to heat the material from the ambient to the critical temperature; and

(iv) providing the calculated power and/or energy;

wherein in step (iii) the power when calculated is calculated according to the formula:

PWM Compensated =PWM Nominal ×(Voltage Nominal ) 2 /(Voltage Loaded ) 2

where:

Voltage Nominal is nominal power supply voltage value

PWM is pulse width modulation; and

the energy when calculated is calculated according to the formula:

PWM Compensated =PWM Nominal ×(Temp Activation −Temp Ambient )/(Temp Activation −Temp Nominal )

where:

Temp Nominal is nominal temperature and is set to 25° C.

Temp Activation is the critical temperature at which the material is adapted to contract and is set to 95° C.

PWM is pulse width modulation.

2. The method of claim 1 wherein in step (iii) both power and energy are calculated.

3. The method of claim 1 , when used in connection with a fastening system.

4. The method of claim 1 , when used in connection with a fastening system which includes at least one sensor monitoring mechanism.

5. The method of claim 1 , wherein in step (iii) energy is calculated and provided via a microprocessor.

6. The method of claim 2 , which includes the step of the microprocessor sensing or reporting, or sensing and reporting, state of the fastening system.