logging in or signing up Balancing Robot Seminar Joshua Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1578 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 07, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Gyrobot a Two Wheel Balancing Robot: Gyrobot a Two Wheel Balancing Robot Larry Barello http://www.barello.net/Robots/GyrobotHow Balancing Works: How Balancing Works Easier to balance high GC object. The Devil is in the details. Balanced Tilted Sense tilt and drive wheels to make robot erect.How Balancing Works: How Balancing Works Restoring Torque = * K = Angular rate (deg/sec) K = some factor based upon robot mass & moment arm. How Balancing Works: How Balancing Works Balance torque = M * g * sin(angle) M is moment arm (center of mass & distance from pivot). g = acceleration of gravity Angle is deviation from balance point Controlling Drive Torque: Controlling Drive Torque As velocity increases, DC motors have less torque (back-EMF) Need to correct this so balance equation can work. Positive velocity feedback Drive = drive + Kv * velocity Kv = factor based upon motor specification.How to move: The robot tilts in the direction of movement. How to move To move robot, need to adjust “balance angle” By adding an error to the angle, the robot will drive a little backwards, then forwards trying to maintain the “balance angle” Error can be simply a negative drive value.Tilt Sensor: Tilt Sensor Gyroscope measures Rate Of Turn. Integrate for angle Gyroscopes drift Drift changes with temperatureTilt Sensor: Tilt Sensor Accelerometers measure gravity. Affected by movement. Very accurate.Fusing Gyro and Tilt sensors: Fusing Gyro and Tilt sensors Weighted Average Filter. Use fraction of error between tilt and gyro Add to integrated Gyro output. Results are fast & drift free The weighted average IIR filter technique can be used to smooth out any noisy signal.Fusing Gyro and Tilt sensors: Fusing Gyro and Tilt sensors Weighted Average Filter. Tiltgyro = Sum(Gyro – Offset) Tiltaccel = sin-1(x/g) Tiltgyro = Tiltgyro + (Tiltaccel – Tiltgyro) * K Gyro Accelerometer + + + - K Tilt Offset - K = weighting factor (1%)Alternate to Tilt Sensor: Alternate to Tilt Sensor F = g * sin(theta) F = A * m A * M = g * sin(theta) Theta = sin-1(A * m/g) Presumably we can use the acceleration of the robot to infer the angle of tilt and correct for gyro drift. (Note: Moment arm not included, formulas must be wrong) m = mass A = Acceleration M/S2 g = Gravity F = forceMotion Sensor: Motion Sensor Encoders measure position and velocity of wheels. Dead reckoning can be derived from encoders and the robots position determined in X, Y and Theta.Current Status: Current Status Motion control not implemented. Navigation disabled. Remote control (Radio link) not implemented. Using acceleration to correct tilt not tried. In short, it doesn’t do anything interesting yet.Additional reading: Additional reading Robots & controls www.barello.net/Papers/Motion_Control Pendulum Joe http://leiwww.epfl.ch Data sheets http://www.systron.com/prodinfo/AQRS.html http://products.analog.com/products/info.asp?product=ADXL202 You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Balancing Robot Seminar Joshua Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINTLite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1578 Category: Education License: All Rights Reserved Like it (0) Dislike it (0) Added: January 07, 2008 This Presentation is Public Favorites: 0 Presentation Description No description available. Comments Posting comment... Premium member Presentation Transcript Gyrobot a Two Wheel Balancing Robot: Gyrobot a Two Wheel Balancing Robot Larry Barello http://www.barello.net/Robots/GyrobotHow Balancing Works: How Balancing Works Easier to balance high GC object. The Devil is in the details. Balanced Tilted Sense tilt and drive wheels to make robot erect.How Balancing Works: How Balancing Works Restoring Torque = * K = Angular rate (deg/sec) K = some factor based upon robot mass & moment arm. How Balancing Works: How Balancing Works Balance torque = M * g * sin(angle) M is moment arm (center of mass & distance from pivot). g = acceleration of gravity Angle is deviation from balance point Controlling Drive Torque: Controlling Drive Torque As velocity increases, DC motors have less torque (back-EMF) Need to correct this so balance equation can work. Positive velocity feedback Drive = drive + Kv * velocity Kv = factor based upon motor specification.How to move: The robot tilts in the direction of movement. How to move To move robot, need to adjust “balance angle” By adding an error to the angle, the robot will drive a little backwards, then forwards trying to maintain the “balance angle” Error can be simply a negative drive value.Tilt Sensor: Tilt Sensor Gyroscope measures Rate Of Turn. Integrate for angle Gyroscopes drift Drift changes with temperatureTilt Sensor: Tilt Sensor Accelerometers measure gravity. Affected by movement. Very accurate.Fusing Gyro and Tilt sensors: Fusing Gyro and Tilt sensors Weighted Average Filter. Use fraction of error between tilt and gyro Add to integrated Gyro output. Results are fast & drift free The weighted average IIR filter technique can be used to smooth out any noisy signal.Fusing Gyro and Tilt sensors: Fusing Gyro and Tilt sensors Weighted Average Filter. Tiltgyro = Sum(Gyro – Offset) Tiltaccel = sin-1(x/g) Tiltgyro = Tiltgyro + (Tiltaccel – Tiltgyro) * K Gyro Accelerometer + + + - K Tilt Offset - K = weighting factor (1%)Alternate to Tilt Sensor: Alternate to Tilt Sensor F = g * sin(theta) F = A * m A * M = g * sin(theta) Theta = sin-1(A * m/g) Presumably we can use the acceleration of the robot to infer the angle of tilt and correct for gyro drift. (Note: Moment arm not included, formulas must be wrong) m = mass A = Acceleration M/S2 g = Gravity F = forceMotion Sensor: Motion Sensor Encoders measure position and velocity of wheels. Dead reckoning can be derived from encoders and the robots position determined in X, Y and Theta.Current Status: Current Status Motion control not implemented. Navigation disabled. Remote control (Radio link) not implemented. Using acceleration to correct tilt not tried. In short, it doesn’t do anything interesting yet.Additional reading: Additional reading Robots & controls www.barello.net/Papers/Motion_Control Pendulum Joe http://leiwww.epfl.ch Data sheets http://www.systron.com/prodinfo/AQRS.html http://products.analog.com/products/info.asp?product=ADXL202