Sekvensstyring av simulert drill

Aim

The aim of the project is to create a sequential control program of a simulated drill in LabVIEW using the state machine principles.

Task

The task is somewhat loosely defined. The purpose of that is to give you practice in making specifications yourself. Where you think that (minor) assumptions are lacking, you should make these yourself, because this is a system that you are going to design yourself, yet following the description given below.

You may use the state-machine example described in this LabVIEW Goldmine as a template for your own solution.

Create a program in LabVIEW that controls the operation of a drill machine according to the description below:

The drilling operation is started (initiated) with a push button. When the drilling operation has been started, the cart is moved down fast until the drill is sufficiently close to the workpiece, and then the drill is turned on, and the cart and drill moves with the slow speed until hole has been made. Then the drill is moved up to the start position, ready for a new job.
The drill (it can be a hand drill) is mounted on a cart with vertical movement in a rig. The movement of the cart (with the drill) is controlled by a control signal that has three possible values: u_down_fast, u_down_slow, and u_up. The speed of the cart is proportional to the value of the control signal.
The drilling (rotation) is started with a control signal having two possible values: u_drill_on and u_drill_off.
The workpiece - in which the drill will drill a hole - is clamped by a mechanism controlled by a control signal with two possible values: u_clamp_on and u_clamp_off. Placing the workpiece in the correct position is not a part of this project task, only the clamping is. You can assume that all possible workpieces have equal dimensions.
A Reset button can interrupt the present operation and bring the drill back to the start position and release the clamps action on the workpiece.
On the front panel of the program it must be indicated at any instant of time which of the states that is the active state. Also, a description of the state with it's actions and possible transitions should be displayed.

Tip 1: The program may consist of one While loop and one Simulation loop running in parallel. The While implements the state machine (for sequential control). The Simulation loop implements the simulated cart.

Tip 2: Position is the integral of speed (hence an integrator block is very useful to have in the Simulation loop).

Tip 3: If you want, you can attach a picture or a drawing of a drill to a numeric indicator (e.g. horizontal slide) to animate the drill/cart motion. This is explained in the description of the State machine in the LabVIEW Goldmine.

Oppdatert 20.10.08 av Finn Haugen, lærer. E-postadresse: finn@techteach.no.