Building the Mongoose Mechatronics Robot: Part 1 Chassis & Gearbox

This is the first of a series of illustrated instructions for assembling the Mongoose Robot kit available from blueroomelectronics

Mongoose highlights:

• Powerful PIC18F2525 microcontroller (32KHz to 32MHz)
• Hardware PWM controlled SN754410 H-Bridge with thermal shutdown
• Differential drive with powerful 114.75:1 gearbox
• Low drag steel ball caster with steel rollers
• Dual optical rotation sensors (108 transitions per revolution)
• Dedicated in circuit programming / debugging connector
• Dedicated TTL Serial port (EUSART)
• Generous 400 hole solderless prototyping area
• Top mounted 20pin I/O for breadboard or LCD display
• Forward facing standoffs with 10pin I/O connector (0.1" PCB compatible)
• 10K trimpot and high brightness LED headlight (programmable)
• Very low center of gravity for stable operation
• Small enough to take anywhere 115mm x 110mm x 60mm

Requires 4x AA NiMH batteries

Programmable in ASM, Swordfish BASIC SE & C18 SE

Part 1: Chassis & Gearbox
Part 2: Electrical, motors & battery holders
Part 3: Electronics, 18F2525 Controller & SN754410 H-Bridge
Part 4: Final assembly, Main driving wheels, solderless breadboard
Part 5: Programming & Testing using Swordfish BASIC SE (free) & the Junebug (PICkit2)
Part 6: Demo code LCD, PWM and Tachometer examples

• Requires a PIC programmer, see the blueroomelectronics site for details.

Step 1: Preparing the Gearbox for the Dual Rotation Sensors

The Mongoose uses a Tamiya Double Gearbox. Part T4 requires a simple modification to allow the optical rotation sensors to monitor wheel rotation.

Simply remove by sanding or cutting away 5mm of material (plastic) from the main gearbox casing as shown in the illustration below.

Comments

[xxlcamlxx]

*Cough* Spam *Cough*

[Kiteman]

Not a wonderful Instructable anyway, as so much is missing, but this smells a little bit like cheap tinned meat.

[GorillazMiko]

This is Part 1 of this Instructable as stated in the title.. it is not a WONDERFUL Instructable, but it is good. I can't wait to see all the parts! How many parts will there be?

[Kiteman]

I know it's "part one", but it also has phrases like "details asap" and "photos coming soon". It would have been much better to wait until the project was properly documented before it was posted, and I still smell the meat.

[GorillazMiko]

True, this person should have finished everything. So basically it should be unpublished, but I cannot do that, and the pictures should be up soon, or things will get ugly. And I smell no meat.

[Kiteman]

Don't you? Sort of like tinned pork? Or tinned ham?

[GorillazMiko]

Nope. :-)

[_soapy_]

I'd say this was spam, really, since it has been 5 months since it was posted, and the promised updates have not been forthcoming. Which is odd, because surely he will sell far more of them by increasing the quality of this Instructable?

[Itsgoofytime]

Bill is Legendary, so don't mess with him, he can jack you up. aka Krumlink

[blueroomelectronics]

The next step is the circuit board assembly, it's a much different process than the mechanical so I thought it would be good to break up the process into several parts.
The real fun begins with the programming, a free "Special Edition" of the Swordfish BASIC compiler for the PIC18Fxxxx microcontrollers is a great match for any robotics kit.
Swordfish BASIC