Collision detection method for a drive unit

• US 9,274,516 B2
• Filed: 09/06/2011
• Issued: 03/01/2016
• Est. Priority Date: 09/07/2010
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Maier, Michael, Wahler, Matthias
• Primary Examiner(s): Satanovsky, Alexander
• Assistant Examiner(s): Kuan, John
• Application Number:
  US13/226,441
• Publication Number:
  US 20120084020A1
• Time in Patent Office: 1,638 Days
• Field of Search: 702/41, 702/96, 702/142, 702/145, 318/255, 318/280, 318/650, 318/823, 318/824
• US Class Current: 1/1
• CPC Class Codes: G05B 19/406 characterised by monitoring or safety G05B19/19 takes precedence
• CPC Class Codes: G05B 19/4062 Monitoring servoloop, e.g. overload of servomotor, loss of feedback or reference
• CPC Class Codes: G05B 2219/37624 Detect collision, blocking by measuring change of velocity or torque
• CPC Class Codes: G05B 2219/40317 For collision avoidance and detection
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A collision detection method for a drive unit including an electric drive motor and a movable component which is driven thereby, wherein an actual torque and an actual acceleration of the electric drive motor are sensed and a collision of the movable component is detected on the basis of an evaluation of a predefinable mathematical combination of the actual torque and the actual acceleration.

Claims

1. A collision detection method for a drive unit including an electric drive motor and a movable component which is driven thereby, comprising:

using a drive control unit to actuate the electric drive motor to drive the movable component;

sensing drive parameters of the electric drive motor during actuation of the electric drive motor, the drive parameters including at least a torque and an acceleration for the electric drive motor;

determining a product of the torque and the acceleration using the drive control unit;

using the drive control unit to compare the product of the torque and the acceleration with a predefined threshold value and to determine whether a collision of the movable component has occurred based on the comparison,

wherein, if a collision is detected, measures which protect the drive unit are taken and/or operating state variables are stored in a storage device.

2. The method according to claim 1, wherein the threshold value is determined during the sensing of the torque and the acceleration using a maximum torque value, sensed within a first time period, and a maximum acceleration value, sensed within a second time period, of the electric drive motor.

3. The method according to claim 2, wherein the threshold value comprises a product of a weighting factor of the maximum torque value, sensed within the first time period, and the maximum acceleration value, sensed within the second time period, of the electric drive motor.

4. The method according to claim 3, wherein the weighting factor is negative.

5. An apparatus comprising a computing unit configured to carry out a method according to claim 1.