| 摘要 |
A user interface device (100) includes a capacitive trackball assembly (108) having a conductive trackball (110) and one or more conductive plates (210, 310, 410, 510, 610) proximate to a surface of the conductive trackball (110), thereby enabling the conductive trackball assembly (108) to operate as a capacitive touch sensor. Each user contact point with the conductive trackball (110) modifies the effective capacitance of the conductive trackball assembly (108). The user interface device (100) senses the effective capacitance of the conductive trackball assembly (108) to discern the number of user contact points on the conductive trackball (110) and uses this information, along with other parameters, such as a concurrent sensed rotation vector of the conductive trackball (110), to identify a user command intended by the user. The identified user command may be transmitted to a controlled system (740) to effectuate or modify an operation at the controlled system (740). |
