HAPTIC FEEDBACK CONTROL METHOD AND APPARATUS FOR A WIRELESS TERMINAL HAVING A TOUCH SCREEN

• US 20110163985A1
• Filed: 01/05/2011
• Published: 07/07/2011
• Est. Priority Date: 01/05/2010
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yun, In-Kuk, BAE, Yu-Dong, Lee, Eun-Hwa, Lee, Jeong-Seok
• Application Number:
  US12/985,113
• Publication Number:
  US 20110163985A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user

Abstract

A haptic feedback control method and apparatus for a wireless terminal including a touch screen. The haptic feedback control method includes receiving a touch input from a user, sensing a voltage or current signal at a position where the touch input is received, transmitting a driving signal to an actuator based on the sensed signal, generating, by the actuator, a vibration output based on the driving signal at the position on the touch screen where the touch input is received, generating a control pulse having a predetermined time delay while generating the vibration output, and stopping the vibration output by applying the control pulse to the vibration output.

Claims

1. A haptic feedback control method for a wireless terminal including a touch screen, the haptic feedback control method comprising:

receiving a touch input from a user;

sensing a signal generated at a position where the touch input is received;

transmitting a driving signal to an actuator based on the sensed signal;

generating, by the actuator, a vibration output based on the driving signal at the position on the touch screen where the touch input is received;

generating a control pulse having a predetermined time delay while generating the vibration output; and

stopping the vibration output by applying the control pulse to the vibration output.

2. The haptic feedback control method of claim 1, wherein the vibration output is a vibration pattern having a periodic pulse waveform.

3. The haptic feedback control method of claim 1, wherein stopping the vibration output comprises stopping the vibration output while maintaining a driving frequency that matches a driving frequency at a time of generating the vibration output.

4. The haptic feedback control method of claim 1, wherein the control pulse is generated using:

at x₁(−

t_d<

t<

0)

x₁(t)=A₁exp{−

ξ

ω

_n(t+t_d)} sin {ω

_d(t+t_d)+φ

₁}

at x_b(0<

t<

t_p)

x_b(t)=A_bexp{−

ξ

ω

_nt} sin {ω

_dt+φ

₂}+B sin(ω

t)

at x₂(t>

t_p)

x₂(t)=exp{−

ξ

ω

_n(t−

t_p)}[x_p0 cos {ω

_d(t−

t_p)}+(v_p0+ξ

ω

_nx_p0)/ω

_d*sin {ω

_d(t−

t_p)}]

If at t=t_p,x_p0=0,v_p0=0x₂=0(t>

t_p)

Because sin(ω

t_p)=0,

x_p0=A_bexp{−

ξ

ω

_nt_p} sin {ω

_dt_p+φ

₂}=0

ω

_dt_p+φ

₂=(2N−

1)π

v_p0=−

ω

_dA_bexp{−

ξ

ω

_nt_p}+Bω

=0

Bω

=ω

_dA_bexp{−

ξ

ω

_nt_p}

A_b, φ

₂ are a function of t_d

wherein t_d represents the predetermined time delay of the control pulse and t_p represents a point in time when the control pulse is applied.

5. The haptic feedback control method of claim 1, wherein an impedance is measured at a driving frequency caused by the vibration output of the actuator and a minimum impedance or a point in time when a waveform of the driving signal input to the actuator matches a phase of a counter electromotive force generated by the actuator is set as a corresponding resonance point to acquire a resonance frequency, thereby setting the predetermined time delay in proportion to a difference between the acquired resonance frequency and the driving frequency.

6. The haptic feedback control method of claim 5, wherein the predetermined time delay uses a range of a ±

1/2 cycle from a 1/2 cycle or 3/2 cycles, when the difference between the driving frequency and the resonance frequency is less than 20 Hz.

7. The haptic feedback control method of claim 1, further comprising blocking a driving voltage for stopping the vibration output of the actuator, before generating the control pulse.

8. A haptic feedback control apparatus for a wireless terminal including a touch screen, the haptic feedback control apparatus comprising:

an actuator for generating a vibration output at a particular vibration frequency;

a frequency generator for generating a driving signal having a frequency within a frequency range; and

a controller for receiving the driving signal to drive the actuator, generating a control pulse having a predetermined time delay, and applying the control pulse to the vibration output in order to abruptly stop the vibration output of the actuator.

9. The haptic feedback control apparatus of claim 8, wherein the controller abruptly stops the vibration output while maintaining a driving frequency that matches a driving frequency at a time of generating the vibration output by the actuator.

10. The haptic feedback control apparatus of claim 8, wherein an impedance is measured at a driving frequency caused by the vibration output of the actuator and a minimum impedance or a point in time when a waveform of the driving signal input to the actuator matches a phase of a counter electromotive force generated by the actuator is set as a corresponding resonance point to acquire a resonance frequency, thereby setting the predetermined time delay in proportion to a difference between the acquired resonance frequency and the driving frequency.