Group members: 

• Steffen Barskrind (Computer) 
• Kristian Meinich Backer-Owe (Computer) 
• Nils Herman Lien Håre (Computer) 
• Joel Soto Escoda (Electro)
• Marius Kul Balsvik (Machine) 
• Kristoffer Andersen (Machine)

Introduction

Our first meeting we started to discuss what we would want to make, and we quickly came to the conclusion that a tracked vehicle would be fun to make, and therefore opted to make a tank that shoot BB pellets. 

The second meeting we decided on the criteria for our project

We are planning to make a tracked vehicle/tank that shoots bio-BBs; and this is our requirements:

A-Requirements: 

1. Autonomous driving
2. Interact with the outside world
3. Movement 
4. Sensor and a camera
5. Controller to interact with the sytem
6. Water resistant  

B-Requirements: 

1. Able to fire/shoot
2. Move in difficult terrain 
3. Electrical power 
4. Remote access to phone
5. Easy disassembly 

C-Requirements: 

1. Amphibious
2. Image recognition
3. Solar Panel 
4. Wipers camera 
5. Patrol feature or fire at specific locations that is autonomous 
6. Smoke launcher 
7. Hydraulic raiser for tracks 
8. Speakers  

After we made the requirements we started to think of the parts we needed. For this project we will buy a few of the parts we need for the arduino and the wheels for the tracks then 3d printing a few parts for the wheels since we are going to need a lot of room to house the parts on the chassis.

What we need for the RC tank:

2x Rc motors  

4x arduino radar  

1x speakers  

1x controller 

1x m4 airsoft 

1x battery 

1x solar panel 

1x burn bag(for battery) 

6x wheels 

2x tracks 

2x cameras 

1x signal receiver  

2x video transmitter

1x Servo engine turret

1x bluetooth receiver 

1x wifi receiver

Computer part:

We’re currently looking at different methods to make the autonomous feature for the vehicle, and one of those are using arduino with ultrasonic sensors. We also want a way to have the vehicle transmit video over wifi so we have a way to store the video it records. 

Since we are 3 computer engineers on the groupe, the programming will be split between us. Where we need to find different methods for different tasks. 

For the video output we’re going to use this Arduino module, that comes with both the camera and the Wi-Fi receiver, so we can transfer the video up to a server and process it there, in addition it also has Bluetooth for usage if we’re not going to be too far away from it

Figure 1.- Arduino esp32 wifi and cam     

For the autonomous driving part, there is a lot of tutorials already on that with the Arduino, so we will be taking a look at that and researching what would be the best alternative for our system. It would also be cool if we can get it to shoot at a specific target that we choose also with the autonomous part, and we will try to do so. 

Another feature we will try is registration how many bullets you have, with that we need a sensor on the housing of the magazine to count the bullets with either a weight sensor or we could just add as many shots to the UI as the magazine provides, then for each shot it will remove one, but that could be an issue if we don’t fill it up full for example, these are things we will have to research. 

Mechanical part: 

We’ve been mostly concerned with the transmission (transfer of power from motor to tracks) and the design of the tracks themselves. Because our project is essentially an RC car we naturally draw on inspiration from such designs.

A major obstacle is the design of the belt. A good choice would be a stiff rubber belt for traction, but with holes so that the teeth of a gear could run it. We can’t produce this accurately so an alternative was to look for a set of roller chains which would fit a gear and then add treads horizontally across the chains for traction and reduced pressure on the ground. Depending on the material of the treads (probably metal) they would have to be coated with something to increase the friction between the threads and the ground.

Another alternative is based on simple friction between wheels/track and then track/ground. This would likely mean wheels and track made of rubber and would also mean additional safety for the drive train as friction between wheel/track would be larger than track/ground which in turn would mean that the track would slip before high strain occurs in the drivetrain.

We’ve also discussed the benefits of having one motor for each track so we can turn the tank by running each track at different speeds or pivoting by running the tracks in opposite directions. 

Additionally we have been evaluating which parts we will order, and which parts we will make at school. As of right now we know we are going to use these bought mechanical components:

Tracks, motors, gears, wheels (Maybe) and so on. Group members have also volunteered to bring useful parts (e.g BB-gun), which we will use if they are compatible with our system. We are also considering 3D printing some parts.

Here is a list of products currently in our order (Ordering these parts does in no way mean we will use all of them. This gives the group an option to make the project harder or easier for ourselves):  Tank kit, Control kit, Antenna, Image sensor, More tracks, Solar panel.w

Figure 2.-  Simplified illustration of how the DIY kit can be modified (cut) to extend overall dimensions of the tank.

Electro part:

Control

As a Smart System, we need a brain that can process and execute orders from the outside world. We are going to use an Arduino UNO R3 board as it. In the board we are going to connect all the sensors directly. But to connect the outputs, motors and servo motors, we need to use a driver shield which has us up to 2 Motors and 16 servo motors connections.

In terms of driving control, we are going to use a remote control with two joystick and 15 programmable buttons. The communication module is based on the emitter (PlayStation commander) and the receiver. The interface it’s based on the WIFI network.

Sensors (Inputs)

We are going to acquire information about the outside world with the sensors because our intention is made an autonomous tank that drives himself. The first autonomous function is the line follower for what we’ll use two infrared sensors in the front part. The second autonomous function is the obstacles avoidant for what we’ll use ultrasonic sensors, concretely three, one in the front and two on the sides.

Figure 3.- Arduino Ultrasonic Sensor      

With all the sensors installed we have our tank ready to acquire information about the environment. With all the sensor data, we’ll process and program different driving modes.

Motors (Outputs)

To make the tank work, we also need the actuators.  We’ve looked for different types of motors in the market (Stepper motors, DC motors and Brushless motors). After studying our case we’ve decided to use the DC motors because we need more power than velocity. Also, we don’t need an extremely control as the Stepper motor gives.

We’ve selected a 12 V DC motor with 120 RPM that has the gear box included and it has a high torque and produce low noise.

Figure 4.- 12V DC Motor

Power

The last part of what we are going to study is the power needed for all system. We know that an Arduino UNO R3 board has 15 V maximum supply input. We’re going to give her with 11,7 V battery case. The case is composed by three 8650 battery type.

In the system we know that there are two parts, loads and sensors. So, for the inputs, we are going to use the 5V output pin from the board that it’s enough for any Arduino sensor. In terms of loads, we know that our driver shield has a power range between 4,5 to 36 V for Motors and 5 to 18 V for Servo Motors. But as we said, we are going to use a 12 V motor that can be supplied with the same supply than Arduino and directly from the battery. After the first tests, we’ll see if we have enough power and enough duration of the batteries. Then we’ll probably add an extra 12 V.

Our intention is to use a solar panel to supply all the installation. But we’ll make that part after tests where we know that all it’s going to work.