Alternative Control for Remote Control Vehicle
Kristina Beck.
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Alternative Control for Remote Control Vehicle
Kristina Beck, Harrison Statham, and Ethan Handte
Project Description
This method of controlling the car without physical contact was inspired by the Theremin, which is an electrical instrument played by holding one’s hand closer or further from a distance sensor. We used the motion of a hand to control speed and direction of a remote controlled car.
Holding one's hand closer to the sensor than the 1/3 meter threshold causes the car to go backwards and holding a hand higher than the threshold causes the car to move forward. Direction of the vehicle is controlled by moving one's hand left and right. The three sensors are set up in a line so if the hand hovers primarily over the rightmost sensor the car will turn right and the opposite is true for the leftmost sensor.
The original Theremin was made using a capacitive distance sensor. Lidar sensors measure distance more quickly than a sonar sensor and more accurately than a capacitive sensor, so we decided to use the VL53L0X. We used three sensors to read an input for speed and direction. These sensors are connected to the mbed at pins 27 and 28 as serial TX and RX. The remote control vehicle was purchased pre-made. We opened the controller and took the circuit board and antenna out of it. We removed push-button inputs for speed and direction and soldered digital control wires in their place which we connected to the mbed.
Parts List
- Mbed
- 3 adafruit VL53L0X lidar sensors
- remote controlled toy car
- SN74LS08N AND gate chip
- breadboard
- wires
- solder
Schematic
Wiring
Information
In the wiring information below, "Radio" refers to the RF control for the vehicle that has been modified. The input pins for forward, reverse, right, and left can be found by putting a voltage at each pin and observing how the car responds. They are also depicted below.
| AND gate | Mbed | Lidar 1 | Lidar 2 | Lidar 3 |
|---|---|---|---|---|
| GND (7) | GND | GND | GND | GND |
| Vcc (14) | Vu (+5 V) | |||
| 1 A (1) | p 26 | |||
| 1 B (2) | p18 | |||
| 1 Y(3) | ~ | SHDN | ||
| 2 A (4) | p26 | |||
| 2B (5) | p19 | |||
| 2Y (6) | ~ | SHDN | ||
| 3A (9) | p26 | |||
| 3B (10) | p20 | |||
| 3Y (8) | ~ | SHDN |
| Mbed | Radio |
|---|---|
| GND | GND (Black) |
| Vout (3.3 V) | Vin (Red) |
| p21 | forward (Yellow) |
| p22 | reverse (Green) |
| p23 | right (Blue) |
| p24 | left (Orange) |
| Mbed | Lidar (1, 2, &3) |
|---|---|
| Vout (3.3 V) | Vin |
| GND | GND |
| p27 | SCL |
| p28 | SDA |
Source Code
Import programAltControlOfRemoteVehicles
Alternative control of remote vehicles.
Last commit 13 Dec 2018 by Harrison Statham
Information
The program above was an adaptation of the code below. It will not compile without the libraries from the following program:
Import programHelloWorld_VL53L0X_LPC1768
Test an Adafruit single VL53L0X breakout board using the mbed LPC1768 and print distance measurement to PC
Last commit 07 Sep 2017 by 
jim hamblen
Photos & Videos
Radio controller outside it's casing.
RF controlled toy car.
Finished circuit with additional LED's to indicate which LIDAR chip is turned on.
Video demo of the basic functionality of the system.
Video of system field test. The interference of the loose wires made the vehicle difficult to control.
PCB Designed to replace breadboard and most wires. In the original circuit, the wires often interfered with the LIDAR readings and sent false signals to the car. This PCB eliminates the need for those wires.
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Alternative Control for Remote Control Vehicle
Page owner: Kristina Beck
Created 01 Dec 2018.
Last updated 13 Dec 2018