Talk:RunBot: a Robogame Robot

Requirements

The robot should have:

• a dimension of about 25cm of radius, 20 cm height
• a speed of about 1 m/sec
• omnidirectional movement (Kamro wheels)
• sensors to avoid obstacles (sonars)
• a camera that can be moved up and down (and eventually left and right)
• wireless connection to a computer (Wi-fi)
• Bluetooth connection
• have power enough to move and transmit for at least 2 hours without recharging
• Have the possibility to recharge autonomously

The robot should cost as less as possible

File with considerations on parts to be ordered

TO DO

• Select HW

 ** ST ARM HW (ask Martino Migliavacca <martino.migliavacca@gmail.com>, GUMSTIX (http://www.gumstix.org/), ARDUINO (http://www.freeduino.org/), other...)
 ** Engines (WWW.robot-Italy.com, http://www.jonathan.it/)
 ** batteries (above, or standard A, AA or AAA type)
 ** Camera (ST smart cameras, with Ethernet wired link)
 ** Sonar (already available (see ROBOWII2.0))
 ** Blue tooth and WI-FI

• Design body (structure and appearance), sensor placement, eventual movements of the camera
• Implement the robot
• test the robot with a simple game (e.g. RoboWII2.0)

== Mice == Will be updated soon == Camera == Will be updated soon

Motion Control

The angle between each wheel is 2*pi/3, which 120 degree.
The front wheels are making a pi/6 angle between the ground.
The positions of the wheels in the coordinate system is as follows.
Wheel 1 is (cos(pi/6),sin(pi/6)) = (0.866,0.5)
Wheel 2 is (cos(pi/6),sin(pi/6)) = (0.866,0.5)
Wheel 3 is (cos(3*pi/2),sin(3*pi/2))=(0,-1)

I wrote simulations in matlab, in two ways.
The first one is using the TriskarOdometry directly, and estimates the necessary wheel speeds to reach the desired frontal, lateral and angular speed of the robot.
The second one is instead giving the motor speeds in terms of rotations and estimates the frontal ,lateral ,angular speed of the robot according to motor speeds.

The matlab code for the motion control simulation is consist of the following files:

-motor_speed.m --This file which takes the motor speed as input and calculates the Vf,Vl,w of the robot.
-TriskarOdometry.m --Giving the input Vf,Vl,w calculates the motor speed
-trajectory.m --The function which draws some trajectories based on the following schema

1) DIRECT MOVEMENT
THE HEAD OF THE ROBOT ALWAYS LOOKING IN A FIXED DIRECTION
2) ANGULAR MOVEMENT
THE ROBOT WILL MOVE IN A CIRCULAR TRAJECTORY WITH FIXED HEAD
DIRECTION
3) SPIN & GO
THE ROBOT EITHER GOES ANGULAR BUT THE HEAD POSITION
IS ALSO CHANGES
4) SPIN & GO DIRECT
THE ROBOT EITHER GOES DIRECT BUT THE HEAD POSITION
IS ALSO CHANGES

-direc_motion.m --DIRECT MOVEMENT
-angular_motion.m --ANGULAR MOVEMENT
-spin_go.m -- SPIN & GO
-spin_go_d.m --SPIN & GO DIRECT
-draw_arrow.m --A function that is used to draw arrow.
File with the matlab files listed above.

Processor Comparison

This is the processor comparison table, the cells without entry is left blank

	Name	Clock Speed	Ram	Storage	Onboard Devices	Power Consumption	Price	OS	Source Page
1	ESOM270	PXA270@520MHz	128 MB SDRAM	32 MB FLASH PMIC	USB device,Camera interface(QCI),USB host	0.8 W @ Full running Mode,100mW @ Deep Sleep mode	76 €	Comes with preinstalled uboot & Linux 2.6.25 or eboot Windows CE 6.0 R2	http://www.e-consystems.com/esom270.asp
2	IGEPv2 BOARD	OMAP3530@720 Mhz	512MB RAM	512MB ONENAND-FLASH	Ethernet 10/100 Mb BaseT.,Wifi IEEE 802.11b/g + Bluetooth 2.0 (Integrated antenna).,1 x USB OTG,1x USB Host		145 €	IGEPv2 running Ubuntu 9.04	http://www.igep-platform.com/index.php?option=com_content&view=article&id=46&Itemid=55
3	Em-x270	Intel's XScale PXA270 CPU, up to 520 MHz	128 Mbyte SDRAM	512 Mbyte Flash Disk	WLAN / WiFi 802.11b/g Interface,Bluetooth interface,Slave and host USB ports, including keyboard and mouse support,100 Mbps Ethernet port	0.2 - 2 W	76 $	ce OR linux	http://www.compulab.co.il/x270cm/html/x270-cm-datasheet.htm
4	S3C2440 Core Board II	Samsung S3C2440A based on ARM920T, 400MHz	64MB SDRAM	64MB NAND Flash	2-ch USB Host controller / 1-ch USB Device controller (ver 1.1),Camera interface ,(Max. 4096 x 4096 pixels input support. 2048 x 2048 pixel input support for scaling)		110$	Windows CE4.2/5.0, 6.0 and Linux2.6	http://www.embedinfo.com/en/list.asp?id=64
5	Overo™ Air COM [GUM3503A]	OMAP 3503 Application Processor with ARM Cortex-A8 CPU 600 MHz	256MB RAM	256MB Flash	802.11(g) and Bluetooth®,USB OTG signals, USB HS Host		199$	Linux 2.6.31 or higher OpenEmbedded	http://www.gumstix.com/store/catalog/product_info.php?products_id=226
6	MX31 TurboG5 Module	Freescale i.MX31 @ 532MHz	128 MB of Mobile DDR	32 MB of Flash	Support for 802.11b/g embedded wireless module,One SD/MMC card slot,One USB 2.0 On-The-Go (OTG) port (H/F/L speed),One USB 2.0 host port (H/F/L speeds),One Camera Sensor Interface,One 10/100BASE-T Ethernet port			Windows CE 5.0 and 6.0 Linux	http://www.eurotech-inc.com/single-board-computer-imx31-com-turbog5.asp

Motor Suggestion

http://www.pololu.com/catalog/product/1092

no load speed: 500 rpm stall torque: 29 kg-cm ~= 0.282 Nm

maximum power output = Pmax = 26.190 rad/s * 0.141 Nm = 3.692 W occuring at W= 250 rpm and t=0.141 Nm

http://www.pololu.com/catalog/product/1085/

no load speed: 470 rpm stall torque : 7 oz ( 0.5 kg-cm ) ~= 0.049 Nm

maximum power output = Pmax = 24.619 rad/s * 0.0245 Nm = 0.603 W occuring at W=235 rpm and t = 0.0245 Nm

calculations made according to the reference paper at the link http://lancet.mit.edu/motors/motors3.html http://lancet.mit.edu/motors/motors4.html

Wheel Specification

2052-3/8X CAT-TRAK

Description

• Standard 2" O.D. - 3/8" Bore Double Row
• Metric 49.2mm O.D. - 9.5mm Plain Bore.
• Recommended max load.
  • Steel Bottom = 25 lbs. 11.3kg.
  • Plywood Surface = 15 lbs. 6.8kg.
• 200# Test Corrugated Bottom = 10 lbs. 4.5kg.
• Weight = 1.75 oz.
• Synthetic rubber coated polypropylene rollers.
• Price:$7.48.
• Source: http://store.kornylak.com/ProductDetails.asp?ProductCode=FXA314

2052BX CAT-TRAK

Description

• Standard 2" O.D. - 1/4" I.D. Bushing Double Row
• Metric 49.2mm O.D. - 6.35mm Bushing
• Recommended max load
  • Steel Bottom = 25 lbs. 11.3kg
  • Plywood Surface = 15 lbs. 6.8kg
• 200# Test Corrugated Bottom = 10 lbs. 4.5kg
• Weight = 1.75 oz
• Synthetic rubber coated polypropylene rollers.
• Price :$7.48
• Source: http://store.kornylak.com/ProductDetails.asp?ProductCode=FXA317

2052KX CAT-TRAK

Description

• Standard 2" O.D. - 1/2" Bore Double Row w/ Keyway
• Metric 49.2mm O.D. - 12.7mm Bore w/ Keyway
• Recommended max load
  • Steel Bottom = 25 lbs. 11.3kg
  • Plywood Surface = 15 lbs. 6.8kg
• 200# Test Corrugated Bottom = 10 lbs. 4.5kg
• Weight = 1.75 oz
• Synthetic rubber coated polypropylene rollers.
• Price :$7.48
• Source: http://store.kornylak.com/ProductDetails.asp?ProductCode=FXA315