In which we look at the steering wheeled base, that is one of the starter platforms with LEGO Boost Creative Toolkit, visit the nomenclature of LEGO Tyres and go out for a spin…Along the way, we go atomic. Now read on…
The recent announcement of the forthcoming Power functions 2.0 reminded me that it has been a while since we looked at the Boost Creative Toolbox. I just wanted to briefly touch on one of the starter models from the Creative Canvas today: the Vehicle hub.
All you need is a little patience.
Towards the end of 2017, Boost became supported on new platforms including the iOS smartphones, and Windows 10- no longer limited to tablets (iOS, Android and Kindle fire). There is also an up to date compatibility list available from the Unofficial LEGO Boost Community Facebook page.
So… Now you can use your new device, how can you reopen the tool boxes for the individual robots, to allow access to the functions in side? Do you need to go through all of the building and programming exercises again?
A work around exists: a 5 second touch (just a touch, you don’t need to push hard on one of those new fangled iPhones) will unlock the activity or tool box, saving you from trying to convince your robot to complete the tasks it was not designed to do.
Trying to work out what those icons/ coding blocks mean? Advancing years, failing eye sight or shrinking screen size means that you can’t quite make it out on your device? A long touch on a coding block will reveal its identity, and what parameters it requires.
The steering chassis is a relatively quick and simple construction, taking about 15 minutes from a standing start. It has driving wheels and front wheels on a steering yoke. The yoke is driven by the external motor driving a 12 tooth bevel gear engaging with a 20 tooth gear, mounted within a forked beam(4558692).
The front wheels are the smaller withØ18×14 w.cross Ø4.8 (6092256), with Ø30, 4×14 tyres(4619323). The front wheels are the Wheel Ø56 (Element ID 6097664), which attaches to the axle via the studs on a round plate which has been threaded over the axle.
Wheel and tyre nomenclature: A quick detour
I was initially baffled a little by the nomenclature used to describe Wheels and Tyres on brickiest and the lego customer service website. Especially with the ‘Ø’ symbol. Now I discover this symbol is employed simply to signify ‘diameter’, typically expressed in millimeters. You learn something every day. At least I have today!
SO: it is fully expressed as ØED x W w.axle type &size
- ED is External diameter (18mm)
- W is the width (14mm)
- Axle type:Cross, diameter (4.8 mm – cross refers to Technic Axle)
The tyre seems to be a little more complicated: ØED, TxW:
- ED = external diameter including tread. (30mm)
- T= Thickness at the rim (not including the tread) (4mm)
- W= Width (14mm)
The larger wheel has an outer diameter of 56mm, but no further information is provided. It does not take a tyre and has a simple 4.8mm hole, which an axle or connector pin can pass through.
The upshot here: the axles for these wheels are approximately 8mm in height apart, with the front, steering wheels much smaller than the rear, driving wheels.
Back to the chassis.
The chassis offers a good number of connections for a vehicle shell to mount onto, either using the studs on top or via connector pins on the sides. It is still easy to access the base of the battery box, to change the batteries once the base is constructed.
Power up/Game On
The first thing that happens when I select a chassis base canvas is a ‘zeroing’ manoeuvre. I had difficulty with this, as it did not routinely return to the midline. The mechanism has about 10 degrees of give – where the axle can wobble with no movement of the gears.
As well as the standard program blocks (begin,end, wait and loop) there are blocks to use the sensor – for colour and distance, as well as to act on detecting sound. The tilt sensor can also be used.
The actual motion is controlled by this block:
It is fairly self explanatory: the Left selector is for speed, middle for steering, and duration. Speed and steering I read as being percentages of maxima. for ‘duration of run’ allegedly in seconds. In reality, this ‘duration’ seems to refer to lengths of the chassis (which in turn is the same as a square on the included Boost Playmat. This inconsistency is being reported.
An opportunity for confusion comes with setting a negative speed (i.e. reverse) and a negative rotation number…it adds up to a positive, but you can see how this might make troubleshooting a challenge.
Setting a program running is pretty straight forward. But I have a problem: after powering up, the steering mechanism does not seem to have zeroed properly- but rather approximately 10º to the right (which equates to -30 on the percentage scale).
I am unsure how to correct this within this program: I WOULD VALUE ANY HINTS AND SUGGESTIONS YOU MIGHT HAVE.
Atomic Batteries to Power, Turbines to Speed
The only way I have found where I can zero the motor is in the ‘fine coding’ atomic level sandbox. This is the area where every command for boost can be accessed, and put together. This is where the easy going, handholding nature of the Boost goes out the window!
In this area, we can find a box that allows for setting the current position to ‘zero’ and all turns are subsequently relative to the current location: the level of control that this area takes you to is incredible, but you do not have the same level of comfort that you had with the prebuilt subroutines with the models (for example, picking Frankie the Cat up by the tail results in a blood curdling screech that only an angry cat can make.).
Because the motor is also designed to work as a rotation sensor, rotating the motor by hand to the zero point should not cause any major issues.
However, it becomes easy to set steering to zero, steer and move, even if it requires more blocks to achieve the same goal. Some people will find this way of thinking fairly intuitive. I will probably struggle…
Of course, sometimes you just want to be able to drive the car, and not worry about trying to program the robot to finesse its own navigation (although this would be a cool, and potentially achievable project). And there is a code block for that: go straight to the teal/turquoise tab, and you can select the joystick: forwards, backwards; left right: this will let you move in each direction.
It takes a little work to finesse this method of control, but for many kids who are looking for a simple way to control their vehicle, this will bear the way to go!
There you go: several ways to control the steerable car chassis in LEGO Boost. I hope this inspires you to explore LEGO Boost beyond the main models.
There have been some great MOCs appearing recently using the Boost Hub, and either the set or other elements. My favourites so far have included JANGBricks Autonomous Tank; Let’s Go Studio’s Squid Man and JK Brickworks Cinnamon Candy Launching Robot.
What have you seen made with Boost that has inspired you? Leave your comments below, and subscribe for updates (publication has been a little irregular lately, so you don’t want to miss anything)
Until next time: