Bmonster Laboratory here today we're going to
review the diy robot smart car chassis kit with speed encoder two wheels and a battery box i
purchased this on amazon for 17.59 currently as of December 2021 and it is compatible with
your Arduino and your raspberry pi which is the purpose of buying this i will make all builds on
this temporary at least for now so that i can use reuse this chassis in the future for future videos
so let's take a look at what we get in the box let's put it together and then make a couple
comments about what we think about the product let's get started right off the bat when you open
the box you see these two large tires they have rubber around the tire and then the plastic in the
middle is pretty solid these are large tires about two and a half inches in diameter which makes that
pretty nice so we got our two tires and then here this black thing here in this plastic sleeve it's
a phone holder for some reason they give you that now here's the bag of components that we will
take a look at here's dc motor number one with an enclosed gearbox this feels like a really
sturdy swivel wheel here's motor number two and some wire that you will need to solder
to the motors and a bag of nuts and bolts and encoders and supports for the motors and a
battery pack that holds four double-a batteries and they include some instructions which honestly
aren't that great but that's just my opinion and then the chassis body which i really do like
it's sturdy it's got a clean look to it it's got a lot of different holes where you can fasten
components don't forget to peel the paper off unless you want a brown chassis that you can't see
through with a bunch of writing all over one side of it to remove the motor you just take the rubber
piece off here pull it out there's a look at the gear that's attached to the motor and the gearbox
don't forget to remove your motor before soldering wires to it otherwise you're going to melt that
rubber piece that holds the gear into the gearbox we have successfully removed all the paper
from our acrylic it's nice clear and clean and another reason i like this is because
you can hot glue just about anything to it and removal is nice and clean and easy as well now
you may hear the fan in the background but it is time to solder those wires onto the motor i'm just
tending the wires right now so that it's easier to attach to the contacts on the motor i'm using a
0.8 millimeter 63-37 tin lead rosin core solder some people don't like to use the lead but it
is easier to work with than the lead-free solder now if you're having a hard time getting your
solder to evenly disperse over the contact you can use what i have is a liquid rosin or you
can use a rosin paste both are perfect for this slip your motor back into the gearbox
here and then reattach your rubber tie down here to keep it connected to the gearbox now i use red 24 gauge wire
for positive and black 24 gauge wire from negative the positive and negative
connection on one motor should be the exact opposite the connection on the other
motor if you want the thing to go forward these black things here are
rotating encoder disc for your uh your motor i've don't have any plans on using
it but i'll go ahead and include that in the build now it's time to install your supports that hold
your motor under the chassis here and as you can see it's supposed to fit snugly just like that i
believe that these are supposed to be identical but this one does not fit in the same hole as
the other one so that's not going to work we'll just have to use this as the outside support for
the motor now it's time to mount the motor to the bottom of the chassis using the two supports on
the side you're going to drive the long screw all the way through and then put the nut on the
other side and tighten it up with a screwdriver then we'll do the same thing with the second screw put that through there's total of two screws
to go through and you tighten that up as well then we'll do exact same thing with motor number
two here we'll mount that and i'll use a pair of pliers to hold the nut because i can't fit my
fingers down there and we'll just tighten it up that way i have to get it pretty tight because
there's a lot of slop is what they call it a lot of movement between the motors once i mount
them i've tightened it pretty tight and i don't want to go any tighter than that so i guess
it's just something we'll have to live with i'm not sure why there's so much movement but i
think it'll be all right for what we want to do and then finally well sorry it's a little bit
dark here but you want to mount your swivel wheel don't forget that now for the switch i'm
just going to take 24 gauge wire and wrap it around the contacts at the bottom of the switch
there just like you see you see some people put it in just like that upside down with the
contact sticking up but i'm going to put it in so that i just have to reach down and press
the button instead of flipping it upside down i'll just put it in this way i do use a
cheap mini glue gun hot glue gun and i will apply some glue just on the side just
a little bit just keep it in place so it doesn't pop out this will keep the button
in place and if i ever need to move it i can just easily pull the glue off no problem i'll
be using a mini breadboard which i can stick i can peel and stick it to the acrylic but i
don't want to do that so i'm just going to add a small spot of hot glue on either side of it
to keep it in place you want to make sure you have enough room for whatever development board
you're using i'm using an uno and it's perfect since there are no holes directly beneath my uno
i'm just using brass standoffs to kind of hold it in place as the robot car is in motion the
screws they provide don't work very well with this battery pack it sticks up above the surface
and scrapes and presses against the batteries so here i'm using my own countersunk screws with a
nut attached to the bottom of it now it's time to attach the tires and you just press them on
pretty simple now to make the connections i use three columns on the mini breadboard and the
first column there on the left i have a white wire from the switch at the bottom right above
that i have a negative wire from the battery pack in the second column i have the second white cable
from the switch and above that i have the two negative wires from each motor in the third column
i have the positive wire from the battery pack and above that i have both of the positive wires from
each motor if you want to do it this way you may want to shift all the wires over closer to one
side so that they're not in the way of the switch overall i'm pretty happy with this product it
is durable i love the tires and i like the clear clean look of the acrylic and the fact that i
can put hot glue on it to hold stuff in place and it easily comes off i also like the motors
and the fact that they come with a an attachment to keep the motor in the gearbox the gearbox is a
big plus too you don't have to use your own gears and the swivel wheel on the front is very durable
but after a lot of use you might see some of the screws pop out so they'll need to re-tighten or
replaced the two things i absolutely dislike about this product is that the none of the holes match
up with any of the development boards that i have therefore i put those standoffs in to hold
my uno in place and secondly the motors are kind of sloppy underneath there should be a
little firmness to them i've tightened them pretty tight i don't want to go any tighter i
don't want to crack the acrylic but those are the only two things so far it's holding up all
right so we'll see time will tell thank you all very much for watching don't forget to give
us a thumbs up and subscribe to the channel be sure to check out our next video where we use
this chassis for our complete robot car build