Hi,
For my project I want to be able to:
- move mass of maximum 1 lb linearly across appx 4-6", while being able to tell my mass to travel to X position (either "move to spot 1, pause, spot 2, pause" or "move 5 sec, pause, 5 sec, pause" or any other way to reach positions).
- And I want to be able to vary the velocity (go faster or slower).
- And I want to be able to use Arduino Uno R3
SET UP 1:
I am thinking of buying this: Pololu - Generic Linear Actuator with Feedback: 4" Stroke, 12V, 1.5"/s (Generic Linear Actuator with Feedback: 4" Stroke, 12V, 1.5"/s)
with this Pololu Dual VNH5019 Motor Driver Shield for Arduino (ash02a) (Pololu Dual VNH5019 Motor Driver Shield for Arduino).
SET UP 2:
or this DC Linear Actuator L16-100-35-12-P - 3571_0 at Phidgets 9 (3571_0 - DC Linear Actuator L16-100-35-12-P)
with maybe this ?? http://arduino.cc/en/Main/ArduinoMotorShieldR3#.UxBGVYVXS-M (Arduino Motor Shield)
QUESTIONS:
Do you think either set up will work for what I am trying to do? Am I missing any parts for either?
Does the Arduino Motor Shield work for just about any kind of motor?
Do you have any suggestions for cheaper alternatives for what I want? I also looked up maybe using a motor and a lead screw but just the parts were pretty expensive by themselves and buying an actuator looked easier maybe. 
Any kind of help for a beginner is appreciated! Thank you very much.