2. LESSON 05 Using the Touch LED

3. The Touch LED The purpose of this lesson is to introduce students to the Touch LED Sensor and how they can be used on a robot.

4. Learning objective: Students will know how touch sensors and colour displays can be used in robotic control Dual Purpose Sensor The Touch LED Sensor is considered a capacitive touch sensor, but can also be used to identify which part of the program is running by lighting up with different colours. The Touch LED Sensor

5. Learning objective: Students will know how touch sensors and colour displays can be used in robotic control capacitive touch Have you ever touched another person and had a static electricity shock? That’s because like a capacitor your body can store an electrical charge. It is this ability that we utilise for touch screen smart phones and tablets - and also in the VEX IQ Touch LED sensor. The sensor has a built in capacitor, when you touch the sensor you add a Capacitor in Parallel (Your finger) and the overall capacitance of the sensor changes. Try to activate the Touch LED with other materials, which work and which do not?

6. Learning objective: Students will understand how to attach the Touch LED Sensor to the Basebot Fitting a Touch LED Fit the Bumper switch as shown on the picture opposite This can be done using four of the 1x1 connector pins. Once in position on the robot, connect the Touch LED to the Brain using a Smart Cable of appropriate length. Fit the Touch LED cable into Port 5 of the Brain Task 1: The build – Fitting the Touch LED sensor

7. Task 2: Using the ‘setTouchLEDHue’ Command Write the above program, and complete the experiment by adjusting the Hue values Test 3: Using the ‘setTouchLEDRGB’ Command Write the above program, and complete the experiment by adjusting the RGB values Learning objective: Students will know how touch sensors and colour displays can be used in robotic control Colour Output Exercise What can you conclude from the above results?

8. Learning objective: Students will be able to program the Basebot using the ‘setTouchLEDcolor’ command Programming a Touch LED Add two ‘setTouchLEDColor’ command blocks to the program, one before and one right after the ‘waitUntil’ command block. Set the first ‘setTouchLEDColor’ to 'touchLED' and 'colorRed' Set the second ‘setTouchLEDColor’ to 'touchLED' and 'colorGreen‘ Using your knowledge of this command, you must now attempt the challenge and complete it using this code. Task 4: Using the ‘setTouchLEDColor’ Command

9. The Challenge: You are working in a busy factory and the Basebot is used to transport goods around the factory from one working bay to another. There are many obstructions, including people working on the factory floor. Recently there have been a couple of instances where people have been bumped into by the robot as they were not sure what it was going to do next. You have been approached by the Factory Health and safety officer to develop a program that navigates the robot around the factory but also indicates what movements the robot is going to do next. These include, move forward, reverse, turn left, turn right and stop. Factory Safety Challenge

11. Sample Solution

12. LESSON - PLENARY As a class, let us consider the following questions? A. What type of sensor is the Touch LED? B. What type of other devices might use a LED Indication? C. In a busy working environment, what other warning devices could a robot have? D. What improvements could you make to the robot to stop it from bumping into people on the factory floor?

13. Today you have:  Learned how the Touch LED Sensor works.  Fitted the Touch LED Sensor to the robot.  Programmed the Basebot using the ‘setTouchLEDColor’, ‘waituntil’ and ‘MultipleMotors’ commands Learning objective: Students will know how touch sensors and colour displays can be used in robotic control. Students will understand how to attach the Touch LED sensor to the Basebot. Students will be able to program the Basebot using the ‘setTouchLEDcolor’ command. Students will be able to design a program for the Basebot to take part in the Factory Safety Challenge. Summary