US 4,929,878 AGranted

Memory mirror control system for vehicles and the like

AssigneeUnited Technologies Automotive, Inc.

InventorRandall F. Hansen

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Abstract

A mirror control system for electrically powered and positioned mirrors (FIG. 1) of the "memory" type for, for example, moving an automotive side view mirror from its current position to a desired "memory" position, and a special algorithm therefor (FIG. 2), which initially moves the mirror toward the final, desired position at a forty-five (45.degree.) degree angle to the vertical and horizontal axes (NE, NW, SW or SE; FIG. 6), for a mirror whose two directional motors have equal speeds (X=Y). If no obstruction (e.g., the mirror's edge) is encountered (FIG. 3), the mirror is moved by both motors until either the vertical or horizontal axis of the final position is encountered, at which axis intersection point the mirror is moved by only the appropriate one of the motors until the final point along the remaining axis is reached; this is the "normal" mode of the algorithm. However, if an obstruction is encountered (left side of FIG. 2; FIGS. 4 and 5), the mirror is moved at a 45.degree. degree angle toward its center point (or a "safe" central position) until its reaches either the center point's vertical (FIG. 4) or horizontal (FIG. 5) axis, and then a single motor is used until the center point is reached. THe analogous "normal" mode is then used to move the mirror to its final position. If the speeds of the horizontal axis and vertical axis direction motors are not equal (X.noteq.Y, respectively), then the angle for the initial movement(s) is "arc tangent (Y.div.X)".

Claims18

Dependent claims

In an electrically powered mirror control system, including

an electrically powered mirror of the "memory" type having at least two position motors driving it about two axes, a first axis (a) and a second axis (b), with each motor having an "on"/"off" switch associated therewith;
and
a memory module, in which at least one selected "memory" position (a.sub.F, b.sub.F) for the mirror with respect to the axes is encoded;
the improvement comprising:
mirror position sensor elements which produce electrical signals indicative of the position (a.sub.X, b.sub.Y) of the mirror with respect to the two axes at a particular point in time;
a computational and control module associated with said sensor elements, the memory module, the motors and the switches, and having comparators for comparing an initial position (a.sub.I, b.sub.I) of the mirror determined by said sensor elements with the "memory" position of the mirror and determining the relative direction of the "memory" position from the initial position, from the relative values of the positions with respect to the axes, and cyclically monitoring the sensed current position of the mirror from the signals from said sensor elements, and generating signals
turning both of the motors "on" through the switches in the directions which moves the mirror toward the "memory" position (a.sub.F, b.sub.F), monitoring the changing position (a.sub.X, b.sub.Y) of the mirror with respect to the axes by the comparators comparing the changing mirror position (a.sub.X, b.sub.Y) to the "memory" position (a.sub.F, b.sub.F), and maintaining both of the motors "on" until at least one of the relationships a.sub.X =a.sub.F and b.sub.Y =b.sub.F is satisfied;
turning "off" the motor which moves the mirror about the axis for which the relationship is satisfied;
and
turning "off" the other motor when the other relationship is satisfied;
moving the mirror from its initial position (a.sub.I, b.sub.I) toward the "memory" position (a.sub.F, b.sub.F).

8 more elements

A method of controlling the movement of an electrically powered mirror including

an electrically powered mirror of the "memory" type having at least two direction motors driving it about two axes, a first axis (a) and a second axis (b), with each motor having an "on"/"off" switch associated therewith;
mirror position sensor elements which produce electrical signals indicative of the current position (a.sub.X, b.sub.Y) of the mirror with respect to the two axes;
a memory module, in which at least one selected "memory" position (a.sub.F, b.sub.F) for the mirror with respect to the axes is encoded;
and
a computational and control module associated with the sensor elements, the memory module, the motors and the switches and having comparators, comprising the following steps:
(a) comparing the initial position (a.sub.L, b.sub.L) of the mirror with the "memory" position of the mirror and determining the relative direction of the "memory" position from the initial position, from the relative values of the positions with respect to the axes, and generating signals;
(b) turning both of the motors "on" through the switches in the directions which moves the mirror toward the "memory" position (a.sub.F, b.sub.F), cyclically monitoring the changing position (a.sub.X, b.sub.Y) of the mirror with respect to the axes from the signals from the sensor elements and using the comparators to compare the changing mirror position (a.sub.X, b.sub.Y) to the "memory" position (a.sub.F, b.sub.F) on a cyclical basis, and maintaining both of the motors "on" until at least one of the relationships a.sub.X =a.sub.F and b.sub.Y =b.sub.F is satisfied;
(c) turning "off" the motor which moves the mirror about the axis for which the relationship is satisfied;
and
(d) turning "off" the other motor when the other relationship is satisfied;
moving the mirror from its initial position (a.sub.L, b.sub.L) toward the "memory" position (a.sub.F, b.sub.F).

8 more elements

Dependencies are inferred from the claim text.