Table of Contents
Introduction
By Jessica Benitez
Ilomilo is tasked with finding the perfect proximity sensing module to utilize for Ilo’s search of Milo. We researched four different types of sensors such as Infrared (IR) like the Time of Flight (TOF) sensor and the Reflective Photoelectric sensor, Light Detection and Ranging (LiDAR), and Ultrasonic. The sensors are then scored out of 10 on their abilities to meet our requirements.
Requirements
Requirements for choosing the right proximity sensor:
- Measurement Range: 0-10 cm
- Working Voltage: 3.3 V
- Power Consumption: < 5 mA
- Dimensions: 5.0 x 5.0 x 5.0 mm
- Weight: < 0.5 0z
- Price: $10- $20
Specifications
| SparkFun Time of Flight VL6180 | SparkFun Ultrasonic Distance Sensor HC-SR04 | SparkFun TFMini-Micro LiDAR Module | OSOYOO IR Infrared Sensor Reflective Photoelectric Light Intensity | |
| Measurement Range: (2 Points) | 0 cm – 25 cm | 2 cm – 400 cm | 30 cm – 1200 cm | 2 cm – 30 cm |
| Working Voltage:
(2 Points) |
3.6V DC (Absolute Max) | 5V DC | 4.5V – 6V DC | 3V – 5V DC |
| Power Consumption:
(1 Point) |
1.7 mA | 15 mA | 0.12 W | Varies from 23 mA – 43 mA |
| Dimensions:
(2 Points) |
4.8 x 2.8 x 1.0 mm | 45 x 20 x 15 mm | 42 x 15 x 16 mm | 44.45 x 12.7 x 6.35 mm |
| Weight:
(2 Points) |
0.32 oz | 0.8 oz | 0.22 oz | 0.16 oz |
| Price:
(1 Point) |
$25.95 | $3.95 | $44.95 | $0.99 |
| Scoring System: (10 Max) | 8 | 4 | 1 | 5 |
Conclusion
Ultimately, we have decided that the best choice for our project is the SparkFun Time of Flight Sensor. We needed something light weight due to the robot being top heavy. It was not the lightest, which is why it lost a point on our grading scale. Because of our design, we needed the smallest sensor in order to minimize its exposure and limit the space it utilizes as we have other components in the head. Although it was not the cheapest, it closer to the range expected given its capabilities, which is why it lost another point on our grading scale. It met all other criteria including the two most important aspects, which are the measurement range and the working voltage. The SparkFun Time of Flight module has absolute range from 0 to 10 cm and has been tested to go above and beyond its range, up to 25 cm. It also has an operating voltage of 2.6 V to 3.0 V , but also includes a 2.8 V regulator which allows up to 3.6 V maximum. Luckily, the 3DoT board that we utilize outputs 3.3 V.