Control device and work management system using same

1. A work management system comprising:

a control device;

a wearable device including a display unit; and a tool, wherein the tool includes:

an image pickup unit; and

a communication unit configured to transmit data of an image captured by the image pickup unit to the control device, wherein the control device includes a processing unit configured to execute a determination process of determining whether or not a work is being performed successfully based on the image captured by the image pickup unit; wherein the processing unit is configured to, in advance of starting of the work by a worker, determine whether or not the worker would perform the work at a correct working site by comparing the image captured by the image pickup unit with an instruction image of a working site to a similarity threshold stored in advance; wherein when it is determined that the worker would perform the work at the correct working site, the processing unit is configured to project on the display unit of the wearable device an image or a message of urging the worker to start the work, and when it is determined that the worker would not perform the work at the correct working site, the processing unit is configured to transmit to the wearable device a signal instructing the worker to capture an image of a working site.

2. The work management system of claim 1 , wherein the work is a work of fastening a fastener by using the tool, and

the image pickup unit is configured to capture the image of the working site where the work is performed.

3. The work management system of claim 2 , wherein the processing unit obtains, in the determination process, a similarity by comparing the captured image with a reference image showing a state in which the fastener is successfully fastened in the working site, and

the processing unit determines whether or not the work is being performed successfully based on a comparison result between the similarity and a threshold set in advance.

4. The work management system of claim 2 , wherein the processing unit obtains, in the determination process, a similarity by comparing the captured image with a reference image showing a state in which the fastener is successfully fastened in the working site, and

the processing unit determines whether or not the work is being performed successfully based on a comparison result between a fastening torque applied to the fastener by the tool and a target torque required for the work and a comparison result between the similarity and a threshold set in advance.

5. The work management system of claim 4 , wherein the tool is a torque wrench including:

a head to which a socket corresponding to a nominal size of the fastener is affixed, the head being rotated to apply a torque to the fastener through the socket;

a detecting unit configured to output an electric signal corresponding to the torque applied to the fastener; and

a torque calculating unit configured to calculate the fastening torque based on the electric signal.

6. The work management system of claim 4 , wherein the tool is an impact driver including:

an impact mechanism configured to generate a pulse-like impact force;

an output shaft to which a bit corresponding to a nominal size of the fastener is affixed, the output shaft being rotated by the impact force applied from the impact mechanism;

a first detecting unit configured to detect a torque applied to the output shaft; and

a second detecting unit configured to detect at least one of an angular velocity of the output shaft and a circumferential acceleration of the output shaft.

7. The work management system of claim 6 , further comprises a torque calculating unit configured to calculate the fastening torque based on a detected value of the first detecting unit and a detected value of the second detecting unit.

8. The work management system of claim 4 , further comprising a host device configured to make communication with the control device,

wherein the host device stores, for each work, data of the captured image and data of the fastening torque transmitted from the control device.

9. The work management system of claim 8 , wherein the host device stores information about devices electrically connected to the control device.

10. The work management system of claim 3 , wherein the processing unit determines whether or not the fastener is inclined with respect to a workpiece based on the similarity obtained by comparing the captured image with the reference image, and

determining whether or not the fastener is inclined with respect to the workpiece includes determining whether or not the fastener is fastened in a direction perpendicular to an installation surface of the workpiece.