Robobot level 1 - Revision history

Jca at 08:17, 29 December 2023

2023-12-29T08:17:22Z

← Older revision		Revision as of 10:17, 29 December 2023
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	Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.		Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.

			== Motor velocity ==

			Each motor has a velocity control, both using a PID controller with the same parameters.

Jca: /* Drive control level */

2023-12-29T08:07:48Z

Drive control level

← Older revision		Revision as of 10:07, 29 December 2023
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	[[File:robobot_level_1.png \| 800px]]		[[File:robobot_level_1.png \| 800px]]

	Figure 2. The lowest level in the control software. The encoder ticks are received form the hardware (from the Teensy microprocessor) in the sensor interface. The encoder values are then modeled into an odometry pose. The pose is used to control the wheel velocity using a PID controller.		Figure 1. The lowest level in the control software. The encoder ticks are received form the hardware (from the Teensy microprocessor) in the sensor interface. The encoder values are then modeled into an odometry pose. The pose is used to control the wheel velocity using a PID controller.
	The desired wheel velocity for each wheel is generated in the mixer from a desired linear and rotational velocity.		The desired wheel velocity for each wheel is generated in the mixer from a desired linear and rotational velocity.

Jca: /* Hardware Teensy */

2023-09-16T13:41:53Z

Hardware Teensy

← Older revision		Revision as of 15:41, 16 September 2023
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	sub svo 50		sub svo 50

	that subscribes to the servo status (for all 5 servos) every 50 ms.		that subscribes to the servo status (for all (4 or 5) servos) every 50 ms.
	The Teensy interface (Teensy i/f) will add the CRC and make sure it is received.		The Teensy interface (Teensy i/f) will add the CRC and make sure it is received.

Jca: /* Hardware Teensy */

2023-09-16T13:40:46Z

Hardware Teensy

← Older revision		Revision as of 15:40, 16 September 2023
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	that subscribes to the servo status (for all 5 servos) every 50 ms.		that subscribes to the servo status (for all 5 servos) every 50 ms.
	The Teensy interface (Teensy~~-if~~) will add the CRC and make sure it is received.		The Teensy interface (Teensy i/f) will add the CRC and make sure it is received.

	== Teensy i/f ==		== Teensy i/f ==

Jca: /* Hardware Teensy */

2023-09-16T13:40:25Z

Hardware Teensy

← Older revision		Revision as of 15:40, 16 September 2023
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	that subscribes to the servo status (for all 5 servos) every 50 ms.		that subscribes to the servo status (for all 5 servos) every 50 ms.
	The Teensy interface will add the CRC and make sure it is received.		The Teensy interface (Teensy-if) will add the CRC and make sure it is received.


	== Teensy i/f ==		== Teensy i/f ==

Jca at 13:39, 16 September 2023

2023-09-16T13:39:06Z

← Older revision		Revision as of 15:39, 16 September 2023
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	Back to [[Robobot architecture]]		Back to [[Robobot architecture]]

			==Drive control level==

	[[File:robobot_level_1.png \| 800px]]		[[File:robobot_level_1.png \| 800px]]

Jca: /* Drive control level */

2023-09-16T13:38:06Z

Drive control level

← Older revision		Revision as of 15:38, 16 September 2023
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	~~== Drive control level==~~

	[[File:robobot_level_1.png \| 800px]]		[[File:robobot_level_1.png \| 800px]]
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	The desired wheel velocity for each wheel is generated in the mixer from a desired linear and rotational velocity.		The desired wheel velocity for each wheel is generated in the mixer from a desired linear and rotational velocity.

	=== Hardware Teensy ===		== Hardware Teensy ==

	The Teensy handles all the sensors connected to the microprocessor and the wheel motors as well as the up to 5 servos.		The Teensy handles all the sensors connected to the microprocessor and the wheel motors as well as the up to 5 servos.
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	=== Teensy i/f ===		== Teensy i/f ==

	This is the Teensy interface controlling the USB interface to the Teensy.		This is the Teensy interface controlling the USB interface to the Teensy.
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	All messages are terminated by a 'new line', a '\n'.		All messages are terminated by a 'new line', a '\n'.

	=====Configuration options=====		===Configuration options===

	In robot.ini, there are these options for the Teensy interface module:		In robot.ini, there are these options for the Teensy interface module:
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	Print is a debug feature to see all communication in the terminal window. Log is the same messages, but send to a file; this can be used for timing analysis of the communication or other debug issues.		Print is a debug feature to see all communication in the terminal window. Log is the same messages, but send to a file; this can be used for timing analysis of the communication or other debug issues.

	=== Encoder ===		== Encoder ==

	The encoder messages hold the encoder count for each wheel, e.g.		The encoder messages hold the encoder count for each wheel, e.g.
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	The last number is debug values that will be removed at some point.		The last number is debug values that will be removed at some point.

	=====Configuration options=====		===Configuration options===

	The streaming sample interval is set in the ini-file for the code, as		The streaming sample interval is set in the ini-file for the code, as
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	Samplerate is here set to 7 ms. Mostly a sample rate of 5 to 15 ms is OK. If much faster than 5ms, the reading of the incoming messages in the Teensy may get overloaded (late). Slower than 15 ms may be too slow for the control loop.		Samplerate is here set to 7 ms. Mostly a sample rate of 5 to 15 ms is OK. If much faster than 5ms, the reading of the incoming messages in the Teensy may get overloaded (late). Slower than 15 ms may be too slow for the control loop.

	=== Pose ===		== Pose ==

	The pose is updated every time new encoder values are available.		The pose is updated every time new encoder values are available.
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	The pose needs information about the drive-train and the distance between the driving wheels to calculate the pose from encoder values.		The pose needs information about the drive-train and the distance between the driving wheels to calculate the pose from encoder values.

	====Configuration====		===Configuration===

	The needed values are set in the ini-file:		The needed values are set in the ini-file:
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	The default motors have 16 magnets in the encoder disk, and as all flanks of the A and B signals are used, this gives 64 ticks per motor revolution.		The default motors have 16 magnets in the encoder disk, and as all flanks of the A and B signals are used, this gives 64 ticks per motor revolution.

	====Wheel velocity====		===Wheel velocity===

	The wheel velocity for each wheel is calculated from the number of encoder ticks (de) time between encoder tick update (dt)		The wheel velocity for each wheel is calculated from the number of encoder ticks (de) time between encoder tick update (dt)
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	If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.		If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.

	====Robot velocity and turn rate====		===Robot velocity and turn rate===

	[[File:pose_calculation.png \| 500px]]		[[File:pose_calculation.png \| 500px]]

	Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.		Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.

Jca: /* Pose */

2023-09-16T13:36:34Z

Pose

← Older revision		Revision as of 15:36, 16 September 2023
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	The pose needs information about the drive-train and the distance between the driving wheels to calculate the pose from encoder values.		The pose needs information about the drive-train and the distance between the driving wheels to calculate the pose from encoder values.

			====Configuration====

	The needed values are set in the ini-file:		The needed values are set in the ini-file:

Jca: /* Robot velocity and turnrate */

2023-09-16T13:35:30Z

Robot velocity and turnrate

← Older revision		Revision as of 15:35, 16 September 2023
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	If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.		If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.

	====Robot velocity and ~~turnrate~~====		====Robot velocity and turn rate====

	[[File:pose_calculation.png \| 500px]]		[[File:pose_calculation.png \| 500px]]

	Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.		Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.

Jca: /* Pose */

2023-09-16T13:35:21Z

Pose

← Older revision		Revision as of 15:35, 16 September 2023
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	If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.		If no encoder ticks are detected in the sample time, then the velocity is estimated using the time since the last detected tick.

	====~~Pose~~====		====Robot velocity and turnrate====

	[[File:pose_calculation.png \| 500px]]		[[File:pose_calculation.png \| 500px]]

	Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.		Figure 3. Definition of the used coordinate systems and how the pose is calculated from wheel velocity.