2. Virtual Basketball: How Well Do You Shoot? Chun Li & Jingwen Ouyang 6.111 Spring 2007

3. System Overview ChunJingwen analog x 10 analog y 10 analog z 10 velocity y 10 velocity z 10 velocity x 10 position x 10 position y 10 position z 10 Calibration & Velocity Calculation vga_colors 24 Game Display vsync, hsync, hblank ADXL330 3-Axis Accelerometer

4. Accelerometer & A/D Converter ADXL330 3-axis Accelerometer ±3g range Operating voltage 3V 300 mV/g sensitivity AD7810 10-bit A/D Converter Sample at 1 kHz

5. Velocity & Position Block Diagram Serial InterfaceIntegrator Determine Release Velocities Serial Interface SCLK CONVST D OUT X 10 SCLK D OUT Y 10 SCLK D OUT Z 10 CONVST To all modules Debounce /Synchronize clk To all modules reset acc_x 10 acc_y 10 acc_z 10 Calibration switch[6:0] height 7 pos_xpos_ypos_z 7 7 7 sens_x 10 sens_y 10 sens_z 10 Integrator reset enable reset enable reset enable vel_x 20 vel_y 20 vel_z 20 rel_x 20 rel_y 20 rel_z 20 ADXL330 3-Axis Accelerometer AD7810 analog_x analog_y analog_z 27Mhz_clock Reset (button[0])

6. Calibration Obtain player height Calculate initial x, y, z positions Why: Variances 0g bias point sensitivity

7. Debouncer/ Synchronizer Game Logic Display Field DCM VGA Controller pixel_clock To All Reset Replay reset_sync replay_sync Initial positions 10 x 3 Initial speeds 10 x 3 Ball x, y, z Positions Shadow Positions labkit_clock pixel_count 10 line_count 10 24 rgb_signal1 x 4 VGA signals Game Display Overview

8. Get Ball position (FSM) Get Shadow Position Status Initial Positions 10 x 3 Initial speeds 10 x 3 ball_x,y,z status Game Logic 2 10 x 3 Shadow_x,y,z 10 x 3

9. Calculations Speed Vz = g t + Vz (only vertical direction has acceleration) * t = time between each frame Position X = Vx t + X Y = Vy t + Y X = Vz t + Z 3D to 2D conversion W = Z + X sin(a) – Y sin(b) U = X cos(a) + Y cos(b)

10. 3D to 2D Converter ball_x,y,z10 x 3ball_x,y 10 x 3 Display Field pixel_count 10 line_count 10 Address Counter For ROM 7 ball_addr ROM rgb_ball24 RGB Controller 24 rgb_signal rgb signals for the shadow, player, scores, and background, which are obtained similarly 24 x 4 Color Mapping 2 color_index

11. Game Display Interface (1) 2 + + + + + 4

12. Game Display Interface (2)

13. Conclusion practice shooting without a court Whenever Game for the Wii