Back in the Driver's Seat
Sam Schmidt always wanted to be a race car driver, following in the footsteps of legends like Mario Andretti. He began professionally racing stock cars in 1995 at the age of 31 and had his first Indy Racing League debut in 1997. Just three years later, tragedy struck.
During a practice lap at the Walt Disney World Speedway in Orlando, Sam crashed, severely injuring his spinal cord and losing the use of his arms and legs. It was a heartbreaking end to a career that he loved—at least, that’s what many thought at the time.
But Sam persevered. In 2001, he founded Schmidt Peterson Motorsports as a way to stay involved in the sport he loves, even as he dreamed of someday driving again. A little more than a decade later, Sam partnered with engineers at Arrow Electronics, an electronic component and computer products provider, to find a way to put him back in the driver’s seat.
The Arrow/SAM team recalls that the idea was to modify a car that could be safely driven at high speeds with head
movements—thus making it possible for a quadriplegic like Sam to effectively ‘take the wheel’. Through sensors and cameras, they believed they could restore independence, control and a sense of accomplishment to a qualified disabled driver, thereby breaking down barriers and opening new physical and emotional horizons.
Sam and Arrow have succeeded beyond even their expectations with the Semi-Autonomous Motorcar otherwise known as SAM.
The first step in the SAM project was for the Arrow team to modify a 2014 Corvette C7 Stingray to allow a qualified quadriplegic driver, namely Sam, to safely operate under racetrack conditions.
In version 1.0, developed in 2013/2014, the team relied on a system of infrared cameras and sensors that directly measure the motion of the head, gradually accelerating in increments of 10 mph. The following year, version 2.0 upgraded the infrared cameras to respond to the driver’s more nuanced head movements. Acceleration and braking were combined into a single mouth device, providing more realistic “pedal” response and improved transitions. With the mouth device, the driver could navigate tight turns left and right, even while driving up and down hills, found on more complex road course tracks.
Essentially, the driver puffed breath into a mouthpiece equipped with a pressure sensor, specifically selected to be sensitive enough to respond to the driver’s (Sam’s) input. The car responds directly via a drive-by-wire attached to the gas pedal. The gas pedal is depressed based on the amount of air pressure Sam created, giving him full control over acceleration—from a smooth gradual increase to a quick burst of speed.
On May 18, 2014, Sam drove a vehicle for the first time since his accident in 2000. As a competing driver at Indianapolis Motor Speedway, he reached a top speed of 97 mph on his 10-mile run. While he did not qualify for the 2014 Indy 500, his incredible feat inspired his family, his team and millions of fans. A week later, he completed more laps at Indy, reaching a top speed of 107 mph.
The next year, Sam drove the twisty 1.9-mile road course at the Long Beach Grand Prix. The Arrow team had upgraded the car cameras with a wider field of view and sensors that were more sensitive and responsive to Sam’s motions, helping to give him more freedom at the controls and improve his racing line.
While it was working, it was not exactly what the Arrow engineers wanted. Maintaining attitude, heading, pitch, roll and yaw are vital for translating head movements to steering output when making course corrections—so they sought to incorporate a GPS/IMU system.
William Pickard, Applications Engineer for Arrow Electronics, explains, “Our goal is to push the use of the GPS/IMU beyond navigation into a driver’s aid. Sam has a natural and learned racing skill that we want to take advantage of by allowing Sam to drive the car to the peak of his ability. To do this, we have developed a human-to-machine interface that allows Sam to steer using the motion of his head and control gas and brake using a tube in his mouth. The goal of the GPS unit is not to make decisions for Sam, but to give him performance data and analytics that allow him to push the car to its limit.”
As part of the third generation SAM system, the team retrofitted a supercharged 6.2-liter V-8 2016 Corvette Z06 (200 more HP than SAM 2.0) with upgraded control systems and a NovAtel® high-accuracy ProPak6™ GNSS receiver for higher system reliability and safety.
Ideal for environments where very high dynamics and frequent interruption of signals can be expected, the ProPak6 receiver is capable of tracking different combinations of GNSS signals including GPS, GLONASS, Galileo, BeiDou, QZSS and SBAS, with integrated L-Band on 240 channels. ProPak6 models contain the OEM638™ GNSS receiver card as their measurement and positioning engine.
The GNSS is tightly linked with machine learning algorithms to closely match Sam’s movements to the vehicle response and performance.
Joshua Willis, Application Engineer at Arrow Electronics, explains, “We integrated the unit to use the high-precision real-time GPS to track the vehicle’s position. This position information is used as part of our engineering and public IoT [Internet of Things] dashboards.”
Essentially, Sam steers the car by looking in the direction he wants to go and continues to use the Sip-and-Puff system developed in the first versions of the car (puff out to accelerate; sip in to brake). However, Sam’s interface was changed in version 3.0 from a racing hat to sunglasses fitted with nine motion sensors that are tracked by an off-the-shelf 4-camera array located on the car’s dashboard. A human-to-machine interface translates the sensor data from the driver’s head motions to a drive-bywire system, all within a fraction of a degree in real-time. The team is currently tracking Sam’s head movement to about millimetre accuracy.
According to Arrow, the modified off-the-shelf electric motors under the wheel take data from the Sip-and-Puff and main guidance computers to control steering and braking—one motor controls the gas and braking, and a second motor controls steering. The Arrow team says the car is also equipped with custom IoT capabilities, developed on the Arrow Connect IoT platform, that enable live streaming and replay of telemetry, driver biometrics, environmental conditions and driver Point of View (POV) video. A custom engineering dashboard allows the team to quickly pinpoint and correct issues in real-time. Sam drove this car in the Indy Grand Prix and the Pikes Peak Hill Climb races, with some impressive results.
On the Track
In 2016, Sam set out to drive the Pikes Peak course with the newly modified GPS-enabled 2016 Corvette Z06—and he did it in 15 minutes flat.
Pickard says, “The Pikes Peak hill climb has lots of turns. During this test, we were able to use the intelligent guidance system to collect and share feedback about the roadway instantaneously to Sam, improve the racing line and take seconds off lap times.”
On May 13, 2017, the Arrow/SAM team put two SAM cars on the Indy Grand Prix road course. On that date, Sam and Mario Andretti “raced” using head controls. The road course is 2.439 miles.
Pickard said, “This race was one of the best events we’ve had to date. Sam and Mario were able to carefully maneuver around a very technical track at high speeds, reaching up to 140 mph. This was the first time Sam has been able to compete against another driver, which was a huge milestone for him and for us. Although Sam lost by a very narrow margin at the finish line, it was a very successful day for the SAM technology and Sam Schmidt personally.”
The 4th generation SAM, currently in development, will primarily focus on mechanical changes to the car with minor software upgrades.
Thus far, the team has developed their control systems on a guidance computer in the vehicle. Moving forward they’d like to integrate more of the cloud and IoT platforms for greater connectivity and improved data analytics as a way to get the best possible performance.
Pickard notes, “There was a day when we couldn’t secure a race track early in the project. The only place to go was a go-cart track. As we were shooting footage, we noticed that Sam was driving a perfect racing line, at every turn, every apex, with this 450 horsepower sports car. We realized that standard level GPS was not going to have nearly the performance and accuracy we needed.”
Of course, for race car drivers, the difference between hitting apex and staying on the track is a matter of feet and, on occasion, inches.
“For example, we’re looking at a race course in Sonoma, and it’s very important to have car attitude, heading, yaw, pitch, roll, inertial and attitude,” says Pickard. “We can’t over or under steer the car. We need high accuracy to achieve optimal performance—so we’ll continue to work on ways to integrate navigation to provide the best real-time data.” The Arrow team is looking at a range of applications such as campus shuttles, forklifts, warehouse equipment, farm equipment, etc. that could be operated using the head control solution. They’re looking to see how SAM technology might expand the employment options for disabled people, especially disabled veterans, in order to increase their productivity and help address some of the emotional challenges they face.
Pickard and the rest of the Arrow team give considerable credit to those organizations who have partnered to help the program thus far. He adds, “We’ve been very lucky in our partnerships. The technology we’re using is all off-the-shelf, systems that are proven, reliable and well-supported. Most importantly, we’ve learned firsthand, with a little help, we can all be the drivers of our own lives.”