PWM output from Analog Pin

I'm building my project which uses 5 ultrasonic sensors and 5 vibration motors running on Arduino UNO clone. And as everyone knows, the ultrasonic sensors are connected to the digital pins in the UNO, where 5 sensors requiring 2 pins each, hence 10 pins usage, which leaves me no options but to use the analog pin as output. No problem so far, since I can use the analog pin to control a transistor to control the vibration motors.

But what I'm trying to achieve is the ability to change the vibrations of the motors through PWM. How can I output PWM signal to the transistors from the analog pins, since I've run out of digital pins?

Thank you very much.

PS: Buying another board is not an options for me, nor buying ANY other components, as I don't have instant access to electronic shops here in Malaysia.

Why not use the Analogue pins in digital mode and use the PWM pins for the motors?

Yeah -as Riva said - analog pins A0-A5 work fine with normal digital io (just do like digitalWrite(A1,HIGH) or whatever).

What they can't do is pwm, you only have the 6 pwm pins that can do that.

Analog pins A6 and A7 (present on the smd version of the 328, not broken out on all arduino boards) are weird and can't be used as digital pins. This is only the case for those two pins on the 328 - there aren't pins like that on any other AVR chip I don't think.

As everyone has pointed out, you seem to be rather muddle-headed about your allocation of pins.

In addition, is there a reason why all five "ping" sensors cannot share the same "ping" pin? The only obvious disadvantage is that they all draw current at the same time.

There might be some concern about picking up pings from adjacent sensors but does that actually matter? In any case, you could probably divide them into two groups so that opposite sides were pinged together and the risk of spurious echoes is negligible.