Sensing where Sensors are!

On the average day I will interact with many, many sensors in different objects. I am looking at devices and objects I use outside my phone or other technologies that have sensors and are immediately apparent. I have chosen to look at the other interactions I have with sensors or devices that have sensors on a daily basis.

The first device I pick up and put on in the morning is my fitness band. I put it on and it is now tracking my movements and logging steps. Inside the device is an accelerometer a gyroscope and a sensor that can track heart rate too. I don’t wear it at night so it doesn’t track my sleep but I do wear it during the day and it gathers step count and heart rate data throughout the day. It uses a small touch screen to interact with onscreen menus too. 

Throughout the day I will interact with the fitness band on several occasions. 

A couple of times a day I will need to run errands and get into my car to do so.

Approaching the car there are 2 ways to gain entry. By pressing the button on the keyfob or when you are close to the car placing your hand on the door handle activates a sensor that knows the fob is in close proximity and unlocks the car.

Once I have opened the car I get in and transfer my wheelchair into the passenger seat. I have to be careful how I place the wheelchair as a sensor inside the seat detects if there is something on it and will set off a seat belt warning if the seat belt is not on. This is very annoying as it is impossible to get the seatbelt over the wheelchair. Positioning is key to ensuring the alarm does not sound. 

Then I put on my own seat belt, adjust the seat and start the engine. If it has been raining or is raining as can be the case a lot of the time in Ireland the sensor in the wind screen will automatically activate the wipers clearing the windscreen. It will repeat this until the windscreen is clear. 

Engaging reverse gear the screen in the center console shows a view of what’s behind the car via a camera sensor mounted in the rear boot/trunk door. There is also proximity sensors front and rear on the car that give feedback audibly when you approach obstacles. 

Once I reverse out of my drive way I engage first gear. The gearbox is automatic and in a modern car I believe that this is electronically operated. The sensor detects the position of the gear stick and engages the transmission which inturn when the accelerator is pressed propels the vehicle forward under initially the electric motor and at higher speeds the petrol engine as the car is hybrid. 

As I am driving there are dozens of sensors all working at the same time to ensure safe driving of the car. Proximity sensors detect vehicles behind as well as infront of the car, wipers work automatically if it rains and on entry and exit of dark areas such as tunnels or at night the headlamps automatically engage by way of sensors detecting light levels. Detecting the light level also changes the screen of the dashboard interface to darkmode or light mode based on the lighting conditions.

When I get to a motorway/highway I have the option to engage dynamic radar cruise control and lane assist. My car will accelerate and decelerate based on the speed of the car I front and keep a specific distance to the car in front based on my initial input. It will do this until it reaches a max speed threshold I have also put into the cruise control the radar for the cruise control is situated behind the badge on the front of the car.

Lane assist detects the lines and barriers on the roadside and steers the car within those lines. You must maintain a grip on the steering wheel but it does relieve some effort in steering. Taking your hand of the wheel the car will audibly alert you to grab the wheel. The sensor used for this is positioned just behind the rear view mirror at the top of the windscreen.

When I get to my destination I will park the car, again the proximity sensors in the front and rear of the car give feedback to let me know how close I am to an obstacle and return an audible tone that tells me. On reversing the rear camera kicks into action again with an overlay giving me the best path to obstacle avoidance as I reverse.

Once parked I then shut down the engine. I open the door and left my wheelchair out and assemble it. I then transfer from the car to my wheelchair. One habit I used to have was once parked I would open the door of the car and then shut down the engine when I had the parking brake engaged. Then I would transfer to my wheelchair. I noticed that the car would start to emit an alert when I did things in this sequence. I think it is to alert the driver to the fact that the door is open in case they leave the vehicle unattended. Once I figured this out I knew what sequence to do in order to prevent it. Locking the car is done by either pressing lock on the key fob or touching the sensor on the door handle. The car will also give an alert if the key is inside the car when you try to lock it or if the key is not present when you try to start it.

There are probably dozens more sensors all working with each other and creating outputs that manipulate my actions into the direction of intent for correct use of features and safe driving. The ones mentioned in this post are the ones that appear to be most obvious to me when driving the car.

One of the more awesome sets of sensors I have interacted with were those positioned inside an exoskeleton when I walked for the first time in 15 years. I am paralyzed from the chest down and have been since a mountain biking accident which ended my career in the military.

With the relevant adjustments made to the exoskeleton to suit my body I position myself beside the exoskeleton and then transfer myself across to the chair it is sitting on. Then with the help of the staff at DCU sports campus the straps are put in place around my legs, waist and chest.

Once this is done a walking aid is placed in front of me and one of the physiotherapists powers on the exoskeleton. There is an audible countdown and the physiotherapist warns me of the exoskeleton standing me up. The motors and actuators engage and then I am lifted to the standing position.

The next stage is to begin taking a step, in the foot plates of the exoskeleton are load sensors. When I lean to one side and slightly forward the load sensor detects the difference in pressure and then activates the motors and actuators in that leg of the exoskeleton to move my leg. So when I lean left and slightly forward the exoskeleton lifts my right leg in a stepping motion. Once I have began to do this in sequence the speed can increase. There is also accelerometers and gyroscopes keeping the position of the exoskeleton corrected and to manage speed for safety purposes.

The physiotherapists also have control of the speed of the motor and actuators reactions to maintain a walking pattern. It is a strange sensation to use the exoskeleton and was incredible to walk again albeit with an aid for the first time in 15 years.

Once the session is over I have to be positioned in-front of a chair and the exoskeleton then by way of the remote control proceeds to the sitting position. I am unstrapped and can return to my wheelchair.

There are so many sensors acting and reacting in real time to our inputs and changing the way we interact with the world through their outputs. As they are more and more ubiquitous we begin to expect certain behaviors from objects we interact with. They are empowering people to engage in new and meaningful ways and in a lot of instances giving back something we don’t get any more of, time!