Method and Apparatus for Positional Reference in an Automated Manufacturing System
Assignee3D Systems, Inc.
InventorsWilliam D. Macy, Ryan Luke Alejo, Nathan D. Eversole
Life of this patent
Estimating the term…
Abstract
Applied within an automated robotic manufacturing system that includes additive manufacturing capabilities, methods and enabling devices are disclosed for achieving precise multi-dimension positional alignment among a plurality of diverse tools that are involved in collaboratively constructing a solid object. The enabling devices according to various embodiments include an automatically deployed contact sensing probe and a tool center point sensor that detects contact with tools in multiple axes. At least one disclosed method advantageously utilizes both sensing devices in complement.
Claims24
An automated additive manufacturing system for forming a solid object upon a build surface disposed within a build space, the system comprising:
- a multi-axis motion control system coupled to execute controlled relative movements between at least one tool head and the build surface;
- at least one tool head, coupled to the motion control system, comprising at least one tool for acting to form the solid object and having a designated tool tip, the tool tip corresponding to a location at which the tool acts upon the solid object when the tool is engaged;
- a contact probe, comprising a first contact-sensing element, coupled to move with the tool head in at least one direction corresponding to movement changing a distance between the first tool head and the build surface;
- a second contact-sensing element disposed within the build space that is not coupled to move with the tool head in the at least one direction;
- a controller configured to control the movements of the motion control system and to receive contact state information from the first contact sensing element and from the second contact sensing element;
- wherein the controller is configured to direct the motion control system to execute a first movement to actuate the first contact sensing element by moving the tool head towards the build surface;
- and
- wherein the controller is configured to direct the motion control system to execute a second movement to actuate at least one of the group of sensors comprising the first contact sensor and the second contact sensor by moving the contact probe towards the second-contact sensing element;
- and
- wherein the controller is configured to direct the motion control system to execute a third movement to actuate the second-contact sensor by moving the tool tip towards the second-contact sensing element.
In an automated manufacturing system comprising a motion control mechanism configured to create motion of at least one tool head relative to a build surface, a method for calibrating the position of a tool tip portion of the tool head relative to the build surface comprising:
- providing a first contact probe, comprising a first contact sensing element, that moves with the tool head;
- providing a second contact sensing element that does not move with the tool head;
- using the motion control mechanism, moving the tool head closer to the build surface to cause contact between the first contact probe and the build surface;
- determining a value for a first coordinate, indicative of positioning by the motion control mechanism to create relative motion between the tool head and the build surface, at which the first sensing element detects contact between the first contact probe and the build surface;
- determining a value for a second coordinate, indicative of positioning by the motion control mechanism to create relative motion between the tool head and the second contact sensing element, at which the first contact probe and second contact sensing element make contact;
- determining a value for a third coordinate, indicative of positioning by the motion control mechanism to create relative motion between the tool head and the second contact sensing element, at which the second contact sensing element detects contact with the tool tip portion of the tool head;
- and
- calculating an offset value between the build surface and the tool tip portion of the tool head as a function of the first, second and third coordinate values.
In an automated manufacturing system comprising a controller, a build surface, at least one first tool head and a motion control system, controlled by signals from the controller, acting to cause relative motion, among at least the build surface and the tool head, according to positional coordinates within a finite build space, a method for indirectly establishing an offset between the build surface and a tool tip portion of the tool head comprising:
- with the motion control system, initiating a first motion that reduces distance between the tool head and the build surface;
- receiving a first signal, from a first contact sensing probe attached to the tool head, indicating that the first motion has brought the contact sensing probe into contact with the build surface;
- storing a first positional coordinate value describing a position of the motion control system that corresponds to receiving the first signal;
- with the motion control system, initiating a second motion of the tool head towards a second contact sensing probe that is not attached to the tool head;
- receiving a second signal, from at least one sensor in the group consisting of the first contact sensing probe and the second contact sensing probe, indicating that the second motion has brought the first contact sensing probe in contact with the second contact sensing probe;
- storing a second positional coordinate value describing a position of the motion control system that corresponds to receiving the second signal;
- with the motion control system, initiating a third motion of the tool tip portion of tool head towards the second contact sensing probe;
- receiving a third signal, from the second contact sensing probe during the third motion, indicating that the tool tip portion has contacted the second contact sensing probe;
- storing the value of at least one third positional coordinate, describing a position of the motion control system that corresponds to the third signal;
- and
- calculating and storing an offset value for the tool tip relative to the build surface as a function of the first positional coordinate value, the second coordinate value and the third positional coordinate value.
A non-transitory computer-readable medium containing instructions which, when executed on a controller of an automated manufacturing system, performs a method for indirectly establishing an offset between a build surface and a tool tip portion of a tool head, the method when executed comprising:
- sending signals to the motion control system to cause a first motion that reduces distance between the tool head and the build surface;
- detecting a first input signal, from a first contact sensing probe attached to the tool head, indicating that the first motion has brought the contact sensing probe into contact with the build surface;
- responsive to detecting the first signal, storing a first positional coordinate value describing positioning of the motion control system upon detecting the first input signal;
- sending signals to the motion control system to cause a second motion of the tool head towards a second contact sensing probe that is not attached to the tool head;
- detecting a second input signal, from at least one of the group consisting of the first contact sensing probe and the second contact sensing probe, indicating that the second motion has brought the first contact sensing probe in contact with the second contact sensing probe;
- responsive to detecting the second signal, storing a second positional coordinate value, describing positioning of the motion control system upon detecting the second input signal;
- sending signals to the motion control system to cause a third motion of the tool tip portion of tool head towards the second contact sensing probe;
- detecting a third input signal, from the second contact sensing probe during the third motion, indicating that the tool tip portion has contacted the second contact sensing probe;
- responsive to detecting the third signal, storing the value of at least one third positional coordinate, describing positioning of the motion control system upon detecting the third input signal;
- calculating and storing an offset value for the tool tip relative to the build surface as a function of the first positional coordinate value, the second coordinate value and the third positional coordinate value.
Dependencies are inferred from the claim text.