DriveMyPhone - Smartphone Controlled 3D Printed Vehicle

DriveMyPhone is a project i have siting on my computer in digital format for the past 6 year now. The concept came around when i was working on my other robotic projects called MobileEarthRover One am MobileEarthRover Two.

I have finally had time to publish it, i did not do it before because of the lack of time (submitting an instructable requires a lot of time and effort), lately i have been too busy building and selling 3D printers at reprapalgarve.

The DriveMyPhone concept has won two competition ideas, 'ideias em caixa 2010' and 'idea2product 2011 Portugal'. Keep in mind that it may not be so innovative now in 2016, but back in 2010 it had some potential.

The DriveMyPhone concept has also won venture capital funding, that did not go as planed. A patent for the model was also submitted, you can read it the attachment in step 4. All idea competition take in account not only the product but also the marketing and sales strategy, so that was also the reason it won, i will not enter in detail in this field because it is out of context here in instructables.

I had a great time participating in idea contests, it is a good way to learn and improve your presentation and marketing skills, and also a opportunity to meet interesting people doing interesting and innovative things.

The DriveMyPhone is intended to be a high mobility robotic/tele-robotic vehicle concept, capable of moving and navigating on land, water and in midair. It can be controlled by a smartphone or by computer using bluethooth and it also features an on-board smartphone option for remote access.

The chassis is equipped with several attachable modules such as the flying module, the object avoiding cleaning module and the telerobotic module. In all, I have spent several hundred hours "refining" the design, changing colors, moving around physical proportions of the wheels and inner chassis components and so on.

Have a look at the video:

Here is a video of the idea competition if you are interested in this kind of things.

Robotic machines and vehicles have generated much interest in recent years due to their great promise for performing repetitive, dangerous, or information gathering tasks in hazardous or remote environments.

The diversity of environments in which these vehicles must operate (space, air, water, ground, and combinations of these) results in a wide variety of vehicle types. Researchers in this field are taking several different approaches in the design, modeling, and control of these vehicles, for each of the four types of environment.

DriveMyPhone Characteristics (in theory):

1. The chassis is capable of the Attachment of new modules that increase and diversify its functionality.

2. The vehicle can move freely (remotely controlled by an operator or autonomously) on land using tank tracks or omni-wheels.

3. The vehicle can move freely (remotely controlled by an operator or autonomously) on water using the air field hollow tank tracks or wheels to float. When the vehicle is in the water, approximately 1/3 of the main chassis will be submerged and the remaining 2/3 will maintain itself above the water.

3.1. The vehicle can move freely (remotely controlled by an operator or autonomously) on the ground only balanced on its two front wheels. This feat is achieved by using the measurements of the inertial measurement unit (accelerometer, gyroscope and magnetometer readings) to maintain its balance.

4. When the vehicle in the position where it is balancing on its 2 front wheels, it can activate the propellers from the flying module to lift (remotely controlled by an operator or autonomously) into the air.

5. To turn the vehicle left or right in midair, it is necessary to create a difference in the speed of rotation of the two propellers. If the upper propeller is turning faster than the bottom propeller the vehicle will spin concentrically in one direction. If the upper propeller is turning slower than the bottom propeller the vehicle will spin concentrically in the other direction previously stated.

6. To move the vehicle frontwards or backwards in midair, it is necessary to change the aerodynamic characteristics of the wind trajectory, this is done my moving the motor attached to the chassis that supports the propeller system. By moving the motor forward the vehicle will lean forward and start moving forward in midair. By moving the motor backwards, the vehicle will lean backwards and start moving backwards in midair.

This project started in 2010, i made 2 prototypes before the 3D printed version, one made out of green cardboard, and the second one made out of laser cut aluminum.

Prototyping never stops, you can always upgrade your designs, the DriveMyPhone is in its 3rd prototype.

The patent system is a very old concept created around1450, it ensures the exclusivity of commercialization of the technology to the inventor/s for a few decades. If approved he/she has the power to exclude the commercialization of the technology to the entire world population, for the benefit of their own interests, which in my opinion reflects a lack of compassion for others and that usually also implies a slow down on the development and third-party innovative contributions in the area.

It's always a challenge to commercialize opensource technology because of competition, but this way, everybody can win a little, instead of the wealth becoming concentrated in the hands of inventors. This is very important in a world where resources are finite and most of the population lives in extreme poverty. In 100 years from now, none of us will be here, and patents create unnecessary suffering to everyone how don't have them.

How can you control the DriveMyPhone, the picture says it all. Basically using a Smartphone or two smartphones.

As i have stated before, i have spent more time on this design than i should have, i was caught in the infinite abyss that is the passion for design, i don't regret the time spent there, i have learned a lot of Computer Assisted Design during this process, and this has helped me on other projects.

I have changed the DriveMyPhone color times too often, my preferred colors are gray and orange and gray and green. Take your time and choose the perfect match before ordering your filament colors :) note that you can change the colors by changing the flexible filament parts.

The List of Materials in order to build a DriveMyPhone prototype unit:

- 1 USB cable for programing the Arduino

- 1 Arduino Nano for now (updating to ATmega 2560 custom Circuit very soon)

- 1 Bluetooth module (BT 4.0 LE ideally)

- 1 IMU GY85 inertial measurement unit or other IMU

- 2 Micro DC gear motor 100RMP 6V with encoders and long shaft (55mm) (left and right wheels)

- 1 Micro DC gear motor 15RPM 6V with encoder and long shaft (55mm) (for rotating shaft)

- 2 Turnigy 1200MAH round lipo battery cell 3.7V

- 2 L298N dc motor driver (prototype, custom board very soon)

- 400gr PLA or ABS filament

- 100gr Flexible filament

- Can of primary paint and final paint (optional)

- 8 M1.6x12 screws and nuts

- 2 M3x40 screws

- 6 M3 unlock nuts

- 1 623ZZ

- 1 or 2 meter wiring cable

- Some soldering wire and shrink tubing

Tools:

- Soldering iron

- Digital Multi-miter

- A pair of files

- A pair of calipers and screwdrivers

- Electric drill for 3D part hole clearance

List of Machines:

- A 3D Printer or a 3D hub near you.

Hard solid 3D printing filament options:

Most of the DriveMyPhone vehicle uses 3D printed parts, the first prototype is printed in PLA and resulted in a functional model. ABS has not been tested for the parts, but there is no reasons for it not to work. and is probably a better solution for the front rims i speculate.

Flexible 3D printing filament options:

For the tires, flexible filament was used, approximately 200gr will be needed. This is the ideal filament choice for the tires.

3D Printing:

In order to print the parts you need to position them in the optimal orientation in relation to the print bed. During the instructable i will show a picture of what i think is the best orientation for each part.

The minimum print size of the printer should be 150mmx150mmx150mm in order fit the DriveMyPhone parts.

Parts:

You can find all part on thingiverse for download:

http://www.thingiverse.com/thing:1565846/#files

While you what for download, warm up your extruders.

The DriveMyPhone has a Minimalist design, the main chassis is composed by 2 shells, the top shell and the bottom shell.The shell has 3mm thickness and 14.5cmx14.5cm.

The chassis is forward dual drive, and has 2 idle wheels on the back. In addition it has a extra motor in the center for attaching modules.

The Bottom shell, has an USB opening for the Arduino nano and support for the inertial measurement unit GY85. It also houses a 624ZZ bearing and 3 Micro DC motors.

Printing parameters:

- 3 to 4 perimeters

- 20 % infill

- 15% support structure

The Top shell, has an USB securing dent in the interior of the structure, serving to hold the Arduino in place. It also houses a 624ZZ bearing and 3 Micro DC motors.

Printing parameters:

- 3 to 4 perimeters

- 20 % infill

- 15% support structure

Pink PLA was used to print all the parts, if we had gray filament we would have used that instead. So in order to get a gray chassis, we had to paint all the parts.

First we applied a primer paint several times before applying the final gray paint.

Spoke design is very interesting, i have spent several dozens of hours looking at different spoke designs online. This research led me to single spoke designs, this solution may introduce some unbalanced weight problems but, om the up side, they look great, and work very good for slow speeds.

The front rims have a small groove to allow the tire to position itself in the center of the tire.

Printing parameters:

- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

The middle of the rim is for fitting the rim center. This design allows you to change the rim center and conserving the rim exterior. This can come in handy for future motor coupling updates.

NOTE: This part is not finished, i will receive a micro DC gear motor with 55mm shaft, when it arrives , this part has to be redesigned in order to make the motor coupling to the RIM.

Printing parameters:

- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

File down the PLA from both parts and insert the center rim part inside the front rim center.Make sure that the center rim is perfectly aligned with the rim, if not the wheel will wobble.

Pink PLA was used to print all the parts, if we had gray filament we would have used that instead. So in order to get a gray chassis, we had to paint all the parts. First we applied a primer paint several times before applying the final gray paint.

The tires are printed using flexible filament. They are 98% scaled for the rim size, this allows them to fit tightly onto the rims while the wheels are spinning.

Printing parameters:
- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

Note: you need 2 tires one normal and one mirrored.

The rear omni wheels are not motorized, they are idle wheels, they rotate on the center axis individually, this allows for less reduction of friction and free rotation.

The omni wheels have a Bearing housing for the 623ZZ bearing, and have 8 shaft holders for the 8 tires.

Printing parameters:

- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

- support 30%

Note: you need 2 rims one normal and one mirrored.

The omni wheels tires are made out of flexible filament. The tires have a center hole to allow the shaft to pass. This hole is a bit bigger then the shaft diameter in order for the wheel to rotate.

3D Printing parameters:

- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

Note: you need 16 tires 8 for each rim.

To assemble the Omni Wheels you need to take out the support structures from the rear rim. Using a drill bit open the 3mm holes (16 holes in total per rim). Need you need to cut 5cm of ABS filament 3mm, this part will serve as a shaft tor the Tire.

The next step is to burn the ends of the 3mm filament in order to avoid for them to come out of the system.

Finally insert the 623ZZ bearing inside a M3x50 screw, than put a small washer, ans insert the screw into the center of the rear rim housing. Afterwords lock the screw with a lock nut and a washer.

This in now ready for the final insertion onto the closed chassis, just lock the system with another lock nut and a washer.

NOTE: I used lithium grease to lubricate inside the small tires in order to minimize friction, and also on the M3x50 screw inside the rim center also for the same reason.

For me, the DriveMyPhone is a piece of art and not a robot :) so this said, it deserves a personal stand for admiration. For other people it might just a piece of colorful plastic, it is normal because design is subjective.

No only for admiration, the 3D printed stand also comes in hand when you need to disassemble the chassis to access its interior.

3D Printing parameters:

- 3 to 4 perimeters 0.4mm nozzle

- 20 % infill

- 20% infill

Now from here on , it gets interesting :) The DriveMyPhone has a center shaft that allows module attachments, i have idealized 3 modules in total:

Attachable modules:

- Smartphone attachable module

- Ultrasonic range finder module

- Mop cleaning module

Work in progress, almost finished. Parts already designed. Keep tuned in for all the goodies.

The Universal Smartphone holder par is designed, i have no t printed it yet, i am waiting for long 55mm micro DC motor with encoder shaft to arrive.

This Module will allow the smartphone to tilt up and down, changing the field of view. This module also allows for remote access (telerobotics via a Skype like software).

The holder is composed by 2 parts the bottom smartphone holder and the top smartphone holder. Have a look at the video for more details:

The attachable module 2 is the ultrasonic mop cleaner, the parts are already designed, i waiting for long 55mm motor shaft to arrive. in order to test them.

The ultrasonic range finder avoids objects and the rover cleans the floor in the mean while.

Grab an old smartphone and prepare it for an experiment :) Double rotors or 4 rotors? we should try 4 rotors like a quad copter.

The DriveMyphone has the following list of electronic components:

1 Arduino Nano (soon to be changed to a costume PCB with ATmega2560)

1 Bluetooth module 4.0 Low Energy

2 L298N DC motor drivers (soon updated to costume PCB)

1 GY85 Inertial measurement unit

2 DC gear motors 100RPM at 6V (soon to be exchanged for micro DC with encoder andshaft with 55mm )

1 DC gear motors 15RPM at 6V (soon to be exchanged for micro DC with encoder and long shaft 55mm with)

The DC Motor drivers, drive the 2 front motors and the center shaft motor. In order for them to fit in the chassis, you need to be trimmed off using a set of sharp players.

Please consult the documentation on how to connect L298N driver to motors, i will not repeat this information here, it is very easy:

Ave a look at this tutorial:

https://www.instructables.com/id/Control-DC-and-stepper-motors-with-L298N-Dual-Moto/

The power for the DriveMyPhone comes from 2 cell battery in series. The Turnigy nano-tech 1200mah 1S 15C Round Cell.

https://www.google.pt/search?q=lipo+round+cell&ie=...

I use 2 cell lipo charger for charging the lipos inside the chassis.

The Micro DC Motors used are temporary, we have 6V Micro DC gear motors 100RMP and 15RPM with 2cm shafts.

These motors will be exchanged for 6V Micro DC gear motors with encoders and 55mm shafts.

Solder 2 wires from the motor to the DC motor driver.

The switch button is located on top of the top of the vehicle, i will find a new place to put it, but it works great on top.

The Arduino Nano USB connector fits on the bottom of the bottom cover. The USB port can be accessed outside the chassis from the bottom of the chassis.

The Arduino nano has only 13 digital pins, this will no be enough pins for all the stuff i what to hook it to, so we are designing a PCB circuit, that will be open source.

The onboard Bluetooth module used is a HM-10 LE Bluetooth 4.0 Module. The Bluetooth is connected to the Arduino Serial port, and is powered by 5V from the Arduino.

The self balancing chassis can be achieved by assisted center shaft arm to position the chassis upright.