1) System Description
  • a. Scope of Supply
  • b. Probe Selection
  • c. Measuring strategy
2) Technical solutions
  • a. Linear guide
  • b. Motors and drivers
  • c. Part List
  • d. Triggering Board
3) Software Solutions and Background
  • a. Profile calculation
  • -Over All Section Widht
    -Tread Width
    -Point to Point Measure

1) System Decription

a. Scope of Supply

Provide a system for 2D profile scanning of AGR tire surface after working process (Standard PC based). Due to requests of 0.1mm accuracy and 500mm max of working range it is necessary to mount the probe head over a fine controlled linear stage (Z Axes) It moves the sensor around the middle of its Working Range while main controlled linear stage (X Axes) moves along scanning area previously set.

b. Probe Selection

For this kind of measures the best solution is an optical probe that ensures reliability (no contact), accuracy and time saving. Selected laser probe has possibility to change Stand Off and Working Range with different optics: this make it the best solution for a lot of measurement devices, and could be used for improved accuracy measurement (see Point 3) The table below shows laser performance (our configuration highlighted):

c. Measuring strategy

Different measuring way may be implemented due to:

-Environment in which the system will work -Scanning time

Operator involvement

-Target Accuracy

These will be an argument under discussion with customer

2) Technical solutions

a. Linear guide From a simple hand drawn idea was designed a simplified Linear Stage drawing in order to achieve a good compromise between a very long measuring stroke and good accuracy. We designed linear stages using high quality standard product to reach these Goals: -Around 35Kg weight for the whole system (see point c.) -All mechanic parts easy to repair and find in the international market. -Compact execution, simple and thought.

A simplified FEA analysis confirms the goodness of the project giving less than 0.01 mm deformation of the cursor applying two opposite forces of 500 N

b. Part List
Description Note Type Vendor
Y axes Rolled Ball Screw Lead 10mm -Stroke 1500 mm BTK2510 THK
Z axes Rolled Ball Screw Lead 05mm -Stroke 500 mm BTK1605 THK
Y axes Caged Ball Guide HSR20R2SS THK
Z axes Caged Ball Guide HSR15 R2SS THK
Laser Probe Conoprobe Optimet
Y Axes digital drive Whistle Elmo
Z Axes digital drive Whistle Elmo
Y Axes Brushless motor 48V 400W enc 2500 ppr Duet 60 Metronics
Z Axes Brushless motor 48V 100W enc 2000 ppr Duet 40 Metronics

c. Triggering Board

Related to measuring strategy that will be adopted, a custom electronic board could be necessary to synchronize linear stage encoder position and Laser data.

This device will be equipped with a 32MByte flash memory that permits more than 2 millions measures for one profile scanning.

Device Features will be probably the following:

-2 High Speed Counter (Axis encoders)

-2 trigger Interrupt (laser Latch)

-32MB Flash memory

3) Software solutions and Background

We have experienced laser probes, linear stages and measuring methods more than five years long. We developed software to directly measures and filter tire profiles and tire surfaces.