This application claims the priority benefit of Taiwan application serial no. 95143158, filed on Nov. 22, 2006. All disclosure of the Taiwan application is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a device and a method for human robot interaction, and more particularly, to a device and a method of tactile sensing for human robot interaction.
2. Description of Related Art
A robot needs diversified inputs to create diversified interactions with human beings. Generally, conventional robots or entertainment toys only have an ON/OFF switch sensor or a large number of array sensors to detect a touch in a large area. Since information of system input signals is too little or too much to be calculated, a diversified human robot interaction cannot be achieved.
In view of the above problems, the present invention provides a tactile sensing device for human robot interaction and a method thereof. At least one set of tactile sensor modules is utilized, and an algorithm is utilized to calculate the timing data for determining a touch pattern, so as to sense magnitudes, ranges, and time of the touch. The device interacts with human through actions or sounds output from an actuator, speaker, or display based upon the obtained information, and thus achieving a diversified interactive solution at a low cost.
The present invention provides a tactile sensing device for human robot interaction, which at least comprises a touch interface, a tactile sensor module, a controller, and an actuating unit. The tactile sensor module coupled to the touch interface is used to sense an external touch, so as to generate a series of timing data corresponding to the external touch. The controller coupled to the tactile sensor module is used to receive the series of timing data, and to determine a touch pattern based on a geometric calculation, so as to generate a control signal. The actuating unit coupled to the controller responses an interactive reaction corresponding to the touch pattern based on the control signal.
Moreover, the present invention also provides a tactile sensing method for human robot interaction, which at least comprises the following steps. An external touch is provided on a touch interface. The external touch is sensed in a tactile sensing manner to generate a series of timing data corresponding to the external touch. A touch pattern corresponding to the external touch is calculated and determined based on a geometric calculation and the series of timing data. According to the touch pattern, an interactive reaction is synthesized and output to the external environment, so as to achieve a preferred human robot interaction.
According to the present invention, the present invention utilizes the timing data of a tactile sensor to determine a touch pattern of the device, so as to synthesize into different actions to generate human robot interactive actions. Moreover, the present invention further uses the tactile sensors and the controller of low cost to detect position changes of an area-type (two-dimensional) touch, thus achieving a multi-functional human robot interaction.
In order to make the aforementioned and other objectives, features, and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
As shown in
Furthermore, the tactile sensor module 12 can be selected as, for example, a pressure sensor, a strength sensor, a capacitance sensor, or a displacement sensor, depending on physical parameters of touch to be detected.
The tactile sensor module 12 can obtain a set of timing data Fn (fT) according to the circumstance of applying a pressure and/or a force on the touch interface 30, where f is a magnitude of the force applied to the tactile sensor module 12, and T is an acquiring time. The tactile sensor module 12 can acquire data at a time interval of Δt. The time interval Δt can be fixed or random. In order to precisely sense an area-type (two-dimensional) touch pattern on the touch interface 30, three tactile sensor modules are preferably used. Of course, the number of the tactile sensor modules used is not particularly restricted in practice.
The controller 10 can acquire the data read by the tactile sensor module 12 via the ADC. Then, F (f, X, Y, T) can be obtained by, for example, a geometric calculation shown in
After determining the touch pattern, the controller 10 transmits a control signal to the actuator 14 via the DAC based on the determined touch pattern. Thus, the actuator 14 responses an interactive reaction corresponding to the external touch. The interactive reaction can be various actions of limbs and trunk to form interactive expressions with different speeds, positions and strengths, or to alter a structural rigidity of the limb and trunk, or to express sounds of voice, music, and pre-recording by a speaker; or to display images, characters, colors, brightness, blink, and graphs on a display device.
Next,
As shown in
fn∝1/ln, where n=1, 2, 3 (1)
f
n
×l
n
/K=F, where K is a constant (2)
In this example, three tactile sensors 12a, 12b, and 12c are used for explanation, which are respectively disposed at vertexes of a triangle with a side length of L.
It is assumed that the acquiring retrieve time T is Δt, and the readings of the three sensing modules 12a, 12b, and 12c are f1, f2, and f3 respectively. The following results can be obtained from above formulas (1) and (2). The ratio of the constants a:b:c can be derived from the readings f1, f2, and f3, and H is a proportional constant.
f
1
:f
2
:f
3=1/l1:1/l2:1/l3
l1:l2:l3=a:b:c
l1=aH, l2=bH, l3=cH (3)
Next, three circle equations are obtained below by taking positions of the tactile sensors 12a (a1, b1), 12b (a2, b2), and 12c (a3, b3), as the circle centers and the respective distances to the stress point l1, l2, and l3 as the radii.
(X−a1)2+(Y−b1)2=l12
(X−a2)2+(Y−b2)2=l22
(X−a3)2+(Y−b3)2=l32 (4)
From the above formulas (3) and (4), three intersection lines with the thress circles can be calculated as follows. Moreover, unknown numbers X, Y, and H can be obtained from the formulas below.
(2a2−2a1)X+(2b2−2b1)Y=l12−l22=(a2−b2)H2
(2a3−2a2)X+(2b3−2b2)Y=l22−l32=(b2−c2)H2
(2a1−2a3)X+(2b1−2b3)Y=l32−l12=(c2−a2)H2 (5)
Then, when T=Δt and the touch position is (X,Y), the magnitude of the touch force is calculated as F=f1×l1/K.
Thus, for every time interval of Δt, the magnitude and the position of the applied force can be calculated, and thereby a touch pattern on the touch interface is determined. It should be noted that the time interval Δt can be identical or not.
Next, the non-linear relationship is illustrated, and the non-linear function is expanded by Taylor's expansion for explanation. In the case of non-linearity, it is assumed that
and thus f1×g(l1)/K=F, where g(l1) is a non-linear polynomial function that can be obtained through experiments. The non-linear function is expanded as follows by Taylor's expansion.
As described above, the difference from the linear case only lies in
At Step S104, a series of timing data is calculated based on the data Fn (f, T) obtained at Step S102. For example, the magnitude F and the position (X, Y) of the force application point can be calculated at several time points through the process in
Next, at Step S106, based upon the series of timing data obtained at Step S104, a touch pattern represented by the series of timing data is determined. After the touch pattern is determined, a corresponding action is synthesized and outputted at Step S108, so as to create an interactive reaction. Otherwise, if the touch pattern is hard to be determined, the data of the tactile sensors are continuously acquired.
For example, after the controller 10 acquires data from the tactile sensors 12a, 12b, and 12c, the timing data at each time point can be calculated, for example, through the above process, and thereby determining the touch pattern. For example, a circular touch in
Another touch pattern is an active tactile sensing, which generally refers to that for example a robot hits an external object during its movement. For example, in
After determining the touch pattern, the controller 10 outputs a control signal to the actuator 14 accordingly, so as to enable the actuator 14 to make a proper interactive reaction to the external environment. For example, when the device (robot) is in an application that the robot head is touched as shown in
In summary, the present invention integrates the controller with the tactile sensors, and utilizes the timing data of the tactile sensors to determine a touch pattern of the device (robot), so that different behaviour actions can be synthesized and interactive actions between the human and the robot can be created. Therefore, the present invention uses tactile sensors and a controller at a low cost to detect changes of touch position in an area-type (two dimensional) manner, thus achieving a multi-functional human robot interaction.
Though the present invention has been disclosed above by the preferred embodiments, they are not intended to limit the present invention. Anybody skilled in the art can make some modifications and variations without departing from the spirit and scope of the present invention. Therefore, the protecting range of the present invention falls in the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
95143158 | Nov 2006 | TW | national |