Control a servo with distance

Place the Uno beside the full size breadboard. Keep USB and the separate servo power supply disconnected while wiring. This view is interactive: drag to turn it, and scroll to zoom. The animation will guide you through each connection. Connect five volts on the Uno to the upper positive rail at contact five. Connect Uno ground to the upper negative rail at contact five. The sensor will use these rails. The lower positive rail stays separate for the servo supply. Place the ultrasonic sensor with its two silver transducers facing the object you want to measure. Its four pins are V C C, trigger, echo, and ground. Use female to male jumper wires to connect this header. Connect the sensor V C C pin to the upper positive rail at contact twenty four. Connect ground to the upper negative rail at contact twenty five. This sensor uses five volts from the Uno, separate from the servo power rail. Connect digital pin seven on the Uno to trigger on the sensor. Then connect digital pin six to echo. The sketch sends a short pulse on trigger, then measures the echo pulse to calculate the distance in centimetres. This is a continuous rotation servo. It controls speed and direction, rather than moving to an exact angle. Check its cable colours: brown or black is ground, red is power, and orange or yellow is the control signal. Connect the servo ground lead to the lower negative rail at contact forty two. Connect the red power lead to the lower positive rail at contact forty one. Male to male jumpers fit into the female sockets on the servo cable. Join the upper and lower negative rails at contact thirty eight. This gives the Uno and servo a common ground. A separate regulated five volt servo supply connects to the lower positive and negative rails at contact forty nine. Leave that supply off for now. Connect digital pin nine on the Uno to the servo signal socket. The sketch uses pulses around fifteen hundred microseconds: the neutral pulse stops rotation, and pulses on either side change speed and direction. Your servo may need a small neutral adjustment. Check your wiring, then connect the square USB plug to the Uno and the other end to your computer. Keep the servo supply off while uploading the program below. Open the App, check that it is ready, then power the unloaded servo from its separate supply. Select distance sensor mode in the App and hold Run. Beyond sixty centimetres, the servo runs at full requested speed. Bring an object closer to slow it down; at fifteen centimetres it stops. Releasing Run or losing a valid echo also stops it.

Place the Uno beside the full size breadboard. Keep USB and the separate servo power supply disconnected while wiring. This view is interactive: drag to turn it, and scroll to zoom. The animation will guide you through each connection.

Connect five volts on the Uno to the upper positive rail at contact five. Connect Uno ground to the upper negative rail at contact five. The sensor will use these rails. The lower positive rail stays separate for the servo supply.

Place the ultrasonic sensor with its two silver transducers facing the object you want to measure. Its four pins are V C C, trigger, echo, and ground. Use female to male jumper wires to connect this header.

Connect the sensor V C C pin to the upper positive rail at contact twenty four. Connect ground to the upper negative rail at contact twenty five. This sensor uses five volts from the Uno, separate from the servo power rail.

Connect digital pin seven on the Uno to trigger on the sensor. Then connect digital pin six to echo. The sketch sends a short pulse on trigger, then measures the echo pulse to calculate the distance in centimetres.

This is a continuous rotation servo. It controls speed and direction, rather than moving to an exact angle. Check its cable colours: brown or black is ground, red is power, and orange or yellow is the control signal.

Connect the servo ground lead to the lower negative rail at contact forty two. Connect the red power lead to the lower positive rail at contact forty one. Male to male jumpers fit into the female sockets on the servo cable.

Join the upper and lower negative rails at contact thirty eight. This gives the Uno and servo a common ground. A separate regulated five volt servo supply connects to the lower positive and negative rails at contact forty nine. Leave that supply off for now.

Connect digital pin nine on the Uno to the servo signal socket. The sketch uses pulses around fifteen hundred microseconds: the neutral pulse stops rotation, and pulses on either side change speed and direction. Your servo may need a small neutral adjustment.

Check your wiring, then connect the square USB plug to the Uno and the other end to your computer. Keep the servo supply off while uploading the program below. Open the App, check that it is ready, then power the unloaded servo from its separate supply.

Select distance sensor mode in the App and hold Run. Beyond sixty centimetres, the servo runs at full requested speed. Bring an object closer to slow it down; at fifteen centimetres it stops. Releasing Run or losing a valid echo also stops it.